Acute Local Irritation Potential of a Novel Citrate-Based Irrigation Solution for Surgical Procedures: An In Situ Evaluation in a Rabbit Model

Acute Local Irritation Potential of a Novel Citrate-Based Irrigation Solution for Surgical Procedures: An In Situ Evaluation in a Rabbit Model | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Acute Local Irritation Potential of a Novel Citrate-Based Irrigation Solution for Surgical Procedures: An In Situ Evaluation in a Rabbit Model Farideh Najafi, Jon E. Minter This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6843131/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Postoperative infections remain a major complication across a wide range of surgical procedures, largely due to bacterial biofilm formation. A novel citrate-based irrigation solution has shown promise in disrupting biofilms and reducing planktonic bacteria without cytotoxic effects. This study evaluates the acute local irritation potential of the solution on rabbit tissues in situ to assess its safety for intraoperative use. Methods: Fifty-eight adult rabbits underwent surgical exposure of articular-cartilage, cranial-dura-mater, mesentery, and pericardium tissues. Tissues were irrigated with either the novel citrate-based solution or a control solution (3% hypertonic saline) for 10–11 minutes. Histopathological evaluations were conducted at 30 minutes, 24 hours, and 7 days post-irrigation to assess tissue response, including inflammation, necrosis, neovascularization, and fibrosis. Results: The solution was classified as non-irritating compared to the control solution across all tissues and time points. When compared to naïve tissues, it was a non-irritant at 30 minutes and 24 hours post-irrigation and a slight irritant at 7 days for articular-cartilage, cranial-dura-mater, and mesentery. For the pericardium, it was a non-irritant at 30 minutes, a slight irritant at 24 hours, and a moderate irritant at 7 days. Conclusion: The novel citrate-based irrigation solution demonstrates minimal acute local irritation when applied to rabbit tissues in situ, with slight to moderate irritation observed in certain tissues at specific time points. These findings support its potential as an intraoperative irrigation solution with minimal risk for irritation, but further studies are necessary to fully assess its safety and long-term effects in clinical applications. Citrate-based irrigation solution Biofilm disruption Tissue irritation Rabbit in situ model Surgical Site Infection Postoperative infections Surgical irrigation solution Figures Figure 1 Introduction Postoperative infections are among the most common and costly complications following surgical procedures. Surgical site infections (SSIs) occur in approximately 0.5–3% of patients undergoing inpatient surgery in the United States, accounting for about 160,000 to 300,000 cases annually. These infections not only increase patient morbidity and mortality but also impose a significant financial burden on the healthcare system, with estimated annual costs ranging from $ 3.5 billion to $ 10 billion [ 1 , 2 ]. A critical factor in the development of SSIs is the formation of bacterial biofilms on surgical sites and implanted materials. Biofilms are complex communities of microorganisms encased within a self-produced extracellular polymeric substance, which confers protection against host immune responses and increases resistance to antimicrobial agents by up to 1,000-fold compared to planktonic bacteria [ 3 – 5 ]. Staphylococcus aureus , a common skin commensal, is frequently implicated in SSIs due to its ability to rapidly form biofilms and evade immune detection [ 6 ]. Traditional intraoperative irrigation solutions, such as normal saline, have limited efficacy in disrupting biofilms and eliminating planktonic bacteria. Various agents, including povidone-iodine (PI) and chlorhexidine gluconate (CHG), have been utilized to enhance antimicrobial activity. However, these solutions often exhibit cytotoxic effects on host tissues, including chondrocytes, osteoblasts, and fibroblasts, necessitating their removal through additional rinsing, which may diminish their residual antimicrobial effects [ 7 , 8 ]. The ideal irrigation solution should effectively eradicate planktonic bacteria and disrupt biofilms while minimizing cytotoxicity to host tissues and maintaining a persistent antimicrobial effect without the need for rinsing [ 9 , 10 ]. A novel citrate-based irrigation solution, XPerience™ (XP) (Next Science LLC, Jacksonville, FL), has recently been introduced. This nontoxic, no-rinse antimicrobial surgical wash has been cleared by the United States Food and Drug Administration. It contains citric acid, sodium citrate, and sodium lauryl sulfate. Citric acid chelates metal ions from the biofilm matrix, disrupting its structural integrity, while sodium lauryl sulfate acts as an antimicrobial surfactant that reduces surface tension and lyses bacterial cells [ 11 , 12 ]. While the antimicrobial properties of citrate-based irrigation solutions are promising [ 13 , 14 ], their safety profile concerning local tissue irritation remains to be thoroughly evaluated. Understanding the potential for acute local irritation is crucial, as it may impact post-operative healing and patient outcomes. Animal models, particularly rabbits, offer a valuable means to assess tissue responses due to their physiological similarities to humans in terms of tissue healing processes [ 15 ]. The purpose of this study was to evaluate the acute local irritation potential of a novel citrate-based irrigation solution when applied to various rabbit tissues in situ, including articular cartilage, cranial dura mater, mesentery, and pericardium. By comparing histological responses at multiple time points to those of a control solution (3% hypertonic saline) and naïve tissues, we aimed to determine the safety of this solution for intraoperative use without causing adverse local tissue responses. Materials and Methods Study Design Between September 28, 2018, and February 11, 2019, an in vivo study was conducted using adult rabbits to evaluate the acute local irritation potential of a novel citrate-based irrigation solution compared to a control solution (3% hypertonic saline). The study protocol was approved by the Institutional Animal Care and Use Committee (IACUC) and adhered to the guidelines set forth by the National Institutes of Health for the care and use of laboratory animals. Test and Control Solutions The test solution was a laboratory-prepared formulation of a citrate-based irrigation solution containing 32.5 g/L citric acid, 31.3 g/L sodium citrate, and 1.0 g/L sodium lauryl sulfate in water. The control solution was a 3% hypertonic saline solution. Animal Allocation Fifty-eight male New Zealand White rabbits (Oryctolagus cuniculus), approximately 15 to 16 weeks of age and weighing between 3.1 and 4.1 kg at study start, were used. Animals were acclimated for at least five days prior to the study under standard laboratory conditions, including a 12-hour light/dark cycle, temperature of 20–22°C, and relative humidity of 30–70%. They were individually housed with ad libitum access to certified commercial feed and potable water. Animals were randomly assigned to two groups: test-treated group and control-treated group. Each group was further subdivided based on the time points for tissue evaluation: 30 minutes, 24 hours, and 7 days post-irrigation, with six or eight animals per subgroup (Table 1). Surgical Procedure The animals were anesthetized using a standard protocol and surgical sites were prepared aseptically. Four tissues were surgically exposed in each animal (Figure 1): Articular Cartilage: The knee joint was accessed via a medial parapatellar approach to expose the femoral condyle. Mesentery: A midline laparotomy was conducted to access the mesenteric tissue. Cranial Dura Mater: A midline scalp incision was made, and a craniotomy was performed to expose the dura mater. Pericardium: A left thoracotomy was performed to expose the pericardial sac. Irrigation Procedure Each exposed tissue site was irrigated with 20 mL of either the test or control solution using a 60 mL syringe to flush at a rate of approximately 2.5 mL/second. The solution was applied directly to the tissue surfaces for a duration of 10–11 minutes to simulate extended intraoperative exposure. After exposure, the solution was removed by blotting with sterile gauze without rinsing the tissue. Muscle and skin layers were then surgically closed. Postoperative Care Non-survival animals were euthanized approximately 30 minutes after irrigation. Survival animals designated for 24-hour and 7-day evaluations were recovered from anesthesia and returned to standard housing. Postoperative analgesia was provided as needed. Animals were monitored postoperatively for any signs of distress, complications, or adverse reactions. Body weights were recorded prior to surgery and at termination. For animals in the 7-day group, body temperatures were monitored daily using microchip transponders. Any temperatures outside the normal range (100.0–104.0°F) were verified with a second reading, and the study director and veterinarian were notified if abnormalities persisted. Necropsy and Tissue Harvesting At scheduled time points (30 minutes, 24 hours, and 7 days post-irrigation), animals were euthanized using an intravenous overdose of sodium pentobarbital. A necropsy was performed, including examination of external body surfaces, all orifices, cranial cavity and contents, thoracic cavity. Treatment sites and corresponding naïve tissues were collected and immersion-fixed in 10% neutral buffered formalin (Table 2). Histological Evaluation Fixed tissues were processed using standard histology techniques, including paraffin embedding, sectioning, and staining with hematoxylin and eosin. A board-certified veterinary pathologist, blinded to the treatment groups, conducted the histopathological evaluations. Local irritation was assessed according to ISO 10993-6 (2016) guidelines. An Irritant Rank Score was calculated using the formula: Irritant Rank Score=Test Article Group Average Score−Control Article Group Average Score Negative values were treated as zero. The level of irritation was categorized as: Non-irritant: 0.0 to 2.9 Slight irritant: 3.0 to 8.9 Moderate irritant: 9.0 to 15.0 Severe irritant: >15 Histopathological assessment included acute inflammation (polymorphonuclear cells), chronic inflammation (lymphocytes and macrophages), necrosis, neovascularization, fibrosis, traumatic myofiber changes, bone formation, soft tissue mineralization, subacute/chronic hemorrhage, foreign body reaction, and fibrous band thickness (Table 3). Statistical Analysis Data were analyzed descriptively to assess the distribution within the study groups. Continuous variables are reported as mean ± standard deviation (SD), while categorical variables are presented as frequency (percentage). Results Administration of Test and Control Articles Both test and control articles were administered without complication. During the first application of the test solution (Group 2, articular cartilage and mesentery irrigation), brown staining was observed around these tissue sites post-irrigation, which was an expected observation due to erythrocyte crenation and associated debris. Mortality and General Health Observations All animals remained healthy throughout the study duration and survived until their scheduled termination at approximately 30 minutes, 24 hours, or 7 days post-irrigation. Daily observations indicated no adverse events attributable to the test or control article exposure. Only one animal required veterinary monitoring for an elevated body temperature (refer to Body Temperature Monitoring ), which resolved without intervention. Body Weight Changes Mean body weights at pre-surgery and termination are summarized in Table 4. Changes in body weight during the 7-day observation period were attributed to the surgical procedures rather than exposure to the test or control articles. Articular Cartilage and Mesentery Exposure: The majority (5 out of 6; 83%) of animals undergoing exposure of the knee joint (articular cartilage) and abdominal cavity (mesentery) lost weight during the in-life phase. Weight loss ranged from 0.1 to 0.5 kg. Cranial Dura Mater Exposure: All animals (6 out of 6; 100%) maintained or gained body weight during the 7-day in-life phase. Weight gain ranged from 0.0 to 0.2 kg. Pericardium Exposure: All animals (8 out of 8; 100%) maintained or lost body weight during the 7-day in-life phase. Weight loss ranged from 0.0 to 0.3 kg. Body Temperature Monitoring Body temperatures remained within the physiological range (100.0–104.0°F) with mean values between 101.1 and 103.9°F (Table 5). Minor fluctuations outside the normal range occurred in individual animals but were neither clinically significant nor treatment-related: Hypothermia: One animal in Group 5 recorded 98.5°F on Day 1 but normalized by Day 2 without clinical concerns. Hyperthermia: One animal in Group 5 reached 105.8°F on Day 1, received veterinary observation, and normalized by Day 2. One animal in Group 1 recorded 104.6°F on Day 4, with subsequent fluctuations remaining near normal. A final animal in Group 3 reached 104.3°F on Day 7 (termination day), requiring no further action. Gross Necropsy Findings Abnormalities were identified in both test and control article-treated animals across various treatment sites. Detailed findings for individual animals are available in Supplementary Tables 1–3. Articular Cartilage and Mesentery Minutes Post-Irrigation: All animals showed macroscopically normal tissues. Hours Post-Test Article Irrigation: One animal exhibited brown granular material in the abdominal cavity and congested intestinal vasculature. Days Post-Irrigation: Discoloration was observed on the lateral side of the knee in most animals, attributed to the surgical procedure rather than treatment with the test or control article. Cranial Dura Mater Minutes Post-Irrigation: The dura mater appeared normal in all animals. Hours Post-Test Article Irrigation: A blood clot was observed at the treatment site in one test-treated animal, attributed to a procedural complication (i.e., during craniotomy, hemorrhage associated with the central cerebral vasculature required the application of hemostatic gauze to the periphery of the defect). Days Post-Irrigation: In the test-treated cohort, one animal displayed a blood clot, and another showed extensive bruising. Both findings were likely due to surgical manipulation and unrelated to the test article. Pericardium Minutes Post-Irrigation: Brown granular discoloration was observed in 2 of 3 (66.7%) test-treated animals. Lung congestion was noted in 1 of 3 (33%) animals in both test and control-treated groups. Hours Post-Irrigation: Fluid accumulation in the left thoracic cavity was observed in both test and control-treated groups: Control-treated: 2 of 2 (100%) animals, with fluid volumes ranging from 2 to 12 mL. Test-treated: 4 of 4 (100%) animals, with fluid volumes ranging from 2 to 7 mL. Days Post-Irrigation: Frank blood or red fluid was present in the thoracic cavity of most control- and all test-treated animals: Control-treated: 3 of 4 (75%) animals, with volumes ranging from 3 to 10 mL. Test-treated: All 4 animals (100%), with volumes ranging from 20 to 30 mL. Histopathological Findings The histopathological findings are summarized below, with the detailed microscopic scores for each study group presented in Supplementary Tables 4–9. Articular Cartilage Minutes Post-Irrigation: Minimal polymorphonuclear cells were present in both the test- and control-treated sites. No significant differences were observed compared to naïve tissue. Hours Post-Irrigation: Slight increase in polymorphonuclear cells in test-treated sites compared to naïve tissue, resulting in a slight irritant ranking. Control-treated sites showed similar responses. Days Post-Irrigation: Tissue responses were similar between the test- and control-treated sites, with mild chronic inflammation and neovascularization attributed to surgical access. Cranial Dura Mater Minutes Post-Irrigation: No significant inflammation or tissue reaction in test- or control-treated sites compared to naïve tissue. Hours Post-Irrigation: Slight increases in polymorphonuclear cells in both groups, with test-treated sites showing minimal differences compared to naïve tissue. Days Post-Irrigation: Mild fibrosis observed in test-treated sites, resulting in a slight irritant ranking compared to naïve tissue. Mesentery Minutes Post-Irrigation: Minimal inflammatory response in both test- and control-treated sites, comparable to naïve tissue. Hours Post-Irrigation: Slight increase in polymorphonuclear cells and neovascularization in test-treated sites compared to naïve tissue, resulting in a slight irritant ranking. Days Post-Irrigation: Mild increases in fibrosis and neovascularization in both groups, attributed to healing processes. Pericardium Minutes Post-Irrigation: Minimal inflammatory infiltrates in test-treated sites, comparable to control-treated and naïve tissues. Hours Post-Irrigation: Increased polymorphonuclear cells in test-treated sites compared to naïve tissue, resulting in a slight irritant ranking. Days Post- Irrigation: Moderate levels of macrophages and polymorphonuclear cells in test-treated sites compared to naïve tissue, resulting in a moderate irritant ranking. Irritation Rankings Irritant Rank Scores for test-treated tissues compared to control article-treated or naïve tissues are shown in Table 6. The derivation and interpretation of these scores for each irrigated site are detailed in Supplementary Tables 10–13. Test- vs. Control-Treated Tissues: The test solution was classified as non-irritating across all tissues and time points when compared to control-treated tissues. The Irritant Rank Scores ranged from -0.5 to 1.7, well below the slight irritant threshold of 3.0. Test-Treated Tissues vs. Naïve Tissues: Articular Cartilage, Mesentery, Cranial Dura Mater: Non-irritant at 30 Minutes Post-Irrigation and 24 Hours Post-Irrigation Slight irritant at 7 Days Post-Irrigation: articular cartilage (score of 3.5), mesentery (score of 3.2), and cranial dura mater (score of 6.1). Pericardium: Non-irritant at 30 Minutes Post-Irrigation Slight irritant at 24 Hours Post-Irrigation. Moderate irritant at 7 Days Post-Irrigation. Discussion The present study evaluated the acute local irritation potential of a novel citrate-based irrigation solution when applied to rabbit tissues in situ, including articular cartilage, cranial dura mater, mesentery, and pericardium. The findings demonstrated that the test solution was a non-irritant compared to the control solution (3% hypertonic saline) across all tissues at all evaluated time points. When compared to naïve tissues, the test solution was classified as a slight irritant in some tissues at certain time points. Our results align with previous in vitro and clinical studies suggesting that citrate-based irrigation solutions exhibit minimal cytotoxicity and are safe for intraoperative use without the need for rinsing [ 11 , 14 ]. Bashyal et al. reported that these solutions effectively reduced planktonic bacteria and disrupted biofilm formation without causing significant harm to host tissues [ 11 ]. This is particularly important given the critical role of biofilms in SSIs and the need for irrigation solutions that are both antimicrobial and biocompatible [ 3 , 4 ]. The test solution evaluated in this study is composed of citric acid, sodium citrate, and sodium lauryl sulfate. Citric acid functions by binding metal ions within the biofilm matrix, thereby weakening its structure, whereas sodium lauryl sulfate serves as an antimicrobial surfactant that lowers surface tension and disrupts bacterial cell membranes [ 12 ]. Preliminary in vitro studies have demonstrated the efficacy of citrate-based irrigation solutions in reducing biofilm burden of multiple bacterial strains, including Staphylococcus, Pseudomonas, Cutibacterium, and Escherichia coli, with reductions of 4-log to 6-log compared to less than 1-log reductions observed with traditional solutions like PI and CHG [ 11 , 13 , 14 ]. Moreover, these solutions have shown minimal cytotoxicity, potentially allowing for extended tissue exposure and a sustained antimicrobial effect without the need for rinsing [ 16 , 17 ]. The slight irritation we observed in some tissues when compared to naïve controls is likely a result of the surgical manipulation inherent in the experimental procedures. Similar observations have been made in studies where surgical access alone can induce inflammatory responses, independent of the test articles used [ 18 ]. For instance, increases in tissue inflammation, neovascularization, and fibrosis are expected physiological responses to surgical interventions and are not necessarily indicative of a deleterious effect of the irrigation solution [ 19 ]. Importantly, the study found no evidence that the test solution caused more tissue response than the control solution in any of the evaluated tissues. In the articular cartilage, with the possible exception of a transient increase in polymorphonuclear cells at 24 hours post-irrigation, tissue responses were comparable between the test and control treatment. Similar observations were made for the mesentery and cranial dura mater, where any slight increases in inflammatory markers were attributed to surgical access rather than the irrigation solution. In the pericardium, while the test solution was classified as a moderate irritant compared to naïve tissue at 7 days post-irrigation, this response might also be related to the surgical procedure. Given the anatomical proximity of the pericardium to the lungs and thorax, and the volume of lavage solution used, these adjacent areas were likewise exposed to the irrigation solutions [ 20 ]. This observation may suggest that citrate-based irrigation solutions could be more irritating to these tissues than control solutions, potentially contributing to effusion and fibrosis. However, the observed changes could also be attributed to differences in hemostasis and fluid absorption affecting postoperative healing [ 19 ]. However, we acknowledge that the current study’s control design, which employed 3% hypertonic saline, does not fully isolate the effects of surgical trauma from those of the irrigation solution. The absence of an additional control group—such as an isotonic saline irrigation—limits the capacity to conclusively differentiate inflammation due to surgery versus that caused by the test solution. This methodological limitation is consistent with critiques in the literature emphasizing the importance of sophisticated controls to parse out confounding variables in biocompatibility studies [ 21 ]. The findings from this animal model provide preliminary evidence supporting the potential safe use of the citrate-based irrigation solution in surgical settings. The solution demonstrated a generally non-irritating profile and has documented antimicrobial properties, positioning it as a promising irrigation option for reducing SSIs without compromising host tissue integrity [ 13 , 22 , 23 ]. Traditional irrigation solutions such as PI and CHG have proven antimicrobial effects but are also known for their cytotoxicity to host tissues, often requiring removal after use [ 7 , 8 , 17 ]. The ability of a citrate-based irrigation solution to remain at the surgical site without rinsing may offer advantages for prolonged antimicrobial activity and streamlined surgical protocols; however, further clinical studies are necessary to fully confirm its safety and efficacy in clinical practice. Limitations While this study provides valuable insights into the acute local irritation potential of a citrate-based irrigation solution, several limitations should be acknowledged. First, as an animal model, the results may not directly translate to human clinical scenarios due to physiological differences between species. Rabbit tissues may respond differently to irrigation solutions compared to human tissues [ 24 ]. Second, the choice of control solution, 3% hypertonic saline, may not represent the most clinically relevant comparison. Solutions commonly used in clinical practice, such as normal saline, povidone-iodine PI, or CHG, might have provided more clinically relevant comparisons. The use of a more standard control would have helped contextualize the findings in the broader scope of orthopedic surgery and irrigation practices. Third, the sample size in this study was relatively small, particularly with the division of animals across multiple tissue sites and time points. This limitation may affect the statistical power of the results and the generalizability of the findings. Larger studies with more animals per subgroup are needed to strengthen the reliability of the conclusions. Additionally, the study focused on acute local irritation over a 7-day period. Long-term effects of the irrigation solution on tissue healing and function were not assessed. Future studies should consider longer follow-up periods to evaluate any delayed or chronic tissue responses that could be relevant for post-operative recovery. Moreover, while the study simulated intraoperative conditions to some extent, the experimental setup cannot fully replicate the complexities of the surgical environment. Factors such as blood flow, the presence of pathogens, and patient comorbidities were not considered, and these elements may influence the tissue response to irrigation solutions in real-world clinical settings. Conclusion Under the conditions of this study, the novel citrate-based irrigation solution demonstrated a generally non-irritating profile when applied to rabbit articular cartilage, cranial dura mater, mesentery, and pericardium tissues in situ. However, when compared to naïve tissues, slight to moderate irritation was observed in some tissues. While these tissue responses were attributed to surgical procedures, the potential contribution of the irrigation solution cannot be entirely excluded. These findings suggest that the solution may be a safe irrigation option with minimal acute local irritation potential, supporting its potential use in surgical settings without the need for rinsing. Additionally, its ability to disrupt biofilms and reduce planktonic bacteria without causing significant harm to host tissues addresses a key need in preventing SSIs. However, further studies, including clinical trials and long-term follow-ups, are needed to confirm the safety and efficacy of this solution in human applications. Future research should aim to validate these findings, assess its role in reducing infection rates, and evaluate its long-term effects on tissue healing and function. Abbreviations SSIs, Surgical Site Infections; PI, Povidone-iodine; CHG, Chlorhexidine gluconate; IACUC, Institutional Animal Care and Use Committee; SD, Standard Deviation Declarations Ethics approval and consent to participate The study protocol was approved by the Institutional Animal Care and Use Committee (IACUC) and adhered to the guidelines set forth by the National Institutes of Health for the care and use of laboratory animals. Consent for publication Not applicable Availability of data and materials Data is provided within the manuscript and supplementary information files. Competing Interests Not applicable Funding This study was sponsored by Next Science, LLC (10550 Deerwood Park Boulevard, Suite 300, Jacksonville, FL 32256, USA). Authors' contributions FN, MD – Conceptualization, Study Design, Ethics Approval & Compliance, Investigation, Data Curation, Data Analysis, Manuscript Writing – Original Draft, Manuscript Writing – Review & Editing, Manuscript Submission, Project Administration. JM, DO – Conceptualization, Supervision, Manuscript Writing – Review & Editing, Critical Revision, Visualization, Resources, Validation. Acknowledgements We gratefully acknowledge the laboratory staff for their invaluable assistance with animal care and histological processing. References Shambhu S, Gordon AS, Liu Y, Pany M, Padula WV, Pronovost PJ, et al. The Burden of Health Care Utilization, Cost, and Mortality Associated with Select Surgical Site Infections. 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Experimental Design and Animal Allocation Across Groups and Time Points Group Administration Number of Animals at Termination Time Point a Article Irrigation Sites Exposure 30 Minutes 24 Hours 7 Days 1 Control b Articular cartilage (right hind limb/knee joint), Mesentery Direct contact for 10–11 minutes; Volume of 20 mL 3 3 3 2 Test c 3 3 3 3 Control Dura mater (cranial) 3 3 3 4 Test 3 3 3 5 Control Pericardium d 3 4 4 6 Test 3 4 4 a Post irrigation. b Hypertonic Saline (3%). c Citrate-based solution. d Due to potential higher mortality associated with thoracotomy recovery, group sizes for pericardium exposure were increased to four animals. Table 2. Treated and Untreated Tissue Sites Across Experimental Groups Group Article Treated Sites Untreated (Naïve) Sites 1 Control a Right hind limb/knee joint (articular cartilage), Intestine joined to abdominal wall (mesentery) Heart, Lungs, and Chest wall (pericardium, myocardium, parietal pleura) 2 Test b Right hind limb/knee joint (articular cartilage), Intestine joined to abdominal wall (mesentery) Heart, Lungs, and Chest wall (pericardium, myocardium, parietal pleura) 3 Control Skull (dura mater) Right hind limb/knee joint (articular cartilage), Intestine joined to abdominal wall (mesentery) 4 Test Skull (dura mater) Right hind limb/knee joint (articular cartilage), Intestine joined to abdominal wall (mesentery) 5 Control Heart, Lungs, and Chest wall (pericardium, myocardium, parietal pleura) Skull (dura mater) 6 Test Heart, Lungs, and Chest wall (pericardium, myocardium, parietal pleura) Skull (dura mater) a Hypertonic Saline (3%). b Citrate-based solution. Table 3. Histopathology Severity Scores (Per Irrigated Site) Score 0 Score 1 Score 2 Score 3 Score 4 Inflammation Polymorphonuclear cells (PMNs), Lymphocytes, Plasma Cells, Eosinophils, Macrophages Absent Minimal (Rare, 1–5/HPF a ) Mild (6–10/HPF) Moderate (Heavy Infiltrate) Marked/Severe (Packed) Multinucleated Giant Cells Absent Minimal (Rare, 1–2/HPF) Mild (3–5/HPF) Moderate (Heavy Infiltrate) Marked/Severe (Sheets) Necrosis b 0 Minimal (Mild) Mild Moderate Marked/Severe Tissue Response Neovascularization Absent Minimal capillary proliferation (focal, 1–3 capillary buds), or small blood vessels (venules, and/or arterioles) Groups of 4–7 capillaries with supporting fibroblastic structures Broad band of capillaries with supporting structures Extensive band of capillaries with supporting fibroblastic structures Fibrosis/Fibrous Band c Fibrous band is not formed (i.e., cellular capsule composed predominantly of inflammatory cells with little fibroplasia), or is too thin to measure Narrow band (100, up to 200 µm Mean Fibrous Band Thickness) Thick band (>200, up to 300 µm Mean Fibrous Band Thickness) Extensive band (>300 µm Mean Fibrous Band Thickness) Granuloma Formation Absent Minimal/Slight (>0 up to 25% of the irrigated site field) Mild (>25 up to 50% of the irrigated site field) Moderate (>50 up to 75% of the irrigated site field) Marked/Severe (>75 up to 100% of the irrigated site field) Traumatic Myofiber Changes Fatty Infiltration Bone Formation d Tissue Ingrowth into the Irrigated Material Soft Tissue Mineralization Hemorrhage, subacute / chronic Foreign Material (other than irrigated material) a HPF = high powered field (40X), averaged over the entire irrigated site. b Necrosis consists of nuclear cellular debris from degenerating inflammatory cells. c The fibrous band score is derived from the average of the mean capsule thickness (in microns) for each of the irrigated sites. d Criteria for bone formation include the presence of one or more of the following features: cartilage, chondrocytes/chondroblasts, new bone/osteoid, osteoblasts/osteocytes, bone marrow Table 4. Mean Body Weights at Pre-Surgery and Termination Time Points Timepoint- Post Irrigation Group Mean ± SD a Prior to Implant Termination 30 Minutes 1 3.3 ± 0.3 3.3 ± 0.3 2 3.4 ± 0.2 3.4 ± 0.2 3 3.5 ± 0.2 3.5 ± 0.2 4 3.3 ± 0.1 3.3 ± 0.2 5 3.6 ± 0.2 3.5 ± 0.3 6 3.7 ± 0.1 3.7 ± 0.1 24 Hours 1 3.6 ± 0.1 3.4 ± 0.1 2 3.3 ± 0.1 3.2 ± 0.1 3 3.4 ± 0.2 3.3 ± 0.2 4 3.4 ± 0.2 3.3 ± 0.1 5 3.5 ± 0.1 3.3 ± 0.1 6 3.7 ± 0.1 3.6 ± 0.1 7 Days 1 3.3 ± 0.2 3.2 ± 0.3 2 3.4 ± 0.3 3.2 ± 0.3 3 3.3 ± 0.1 3.4 ± 0.1 4 3.5 ± 0.2 3.7 ± 0.2 5 3.9 ± 0.2 3.8 ± 0.2 6 3.4 ± 0.2 3.3 ± 0.2 a SD = standard deviation Table 5. Daily Mean Body Temperatures (°F) Across Different Irrigated Sites for 7-Day Survival Animals Site Timepoint Mean ± SD a Control article b Test article c Articular cartilage and mesentery Day 1 103.4 ± 0.1 103.4 ± 0.2 Day 2 103.0 ± 0.5 103.1 ± 0.3 Day 3 103.0 ± 0.4 103.3 ± 0.6 Day 4 103.8 ± 0.9 103.3 ± 0.1 Day 5 102.9 ± 0.4 103.6 ± 0.3 Day 6 103.2 ± 0.9 103.5 ± 0.3 Day 7 103.5 ± 0.4 103.7 ± 0.3 Cranial dura mater Day 1 102.8 ± 0.4 102.9 ± 0.7 Day 2 103.1 ± 0.8 102.9 ± 0.4 Day 3 102.3 ± 0.4 102.8 ± 0.7 Day 4 102.8 ± 0.3 102.5 ± 0.2 Day 5 103.0 ± 1.0 102.6 ± 0.3 Day 6 102.8 ± 0.8 102.8 ± 0.5 Day 7 103.9 ± 0.4 103.8 ± 0.2 Pericardium Day 1 102.0 ± 3.0 101.3 ± 1.0 Day 2 101.1 ± 0.5 101.3 ± 0.7 Day 3 101.6 ± 0.5 101.3 ± 0.8 Day 4 101.0 ± 0.7 100.8 ± 0.8 Day 5 101.8 ± 0.7 101.7 ± 0.9 Day 6 102.0 ± 0.7 101.7 ± 0.5 Day 7 102.3 ± 1.2 102.2 ± 0.8 a SD = standard deviation b Hypertonic Saline (3%). c Citrate-based solution. Table 6. Irritant Rank Scores for Test Solution Across Different Tissue Sites and Time Points Site Timepoint- Post Irrigation Tissue for Comparison Control Article-Treated Naïve Untreated Tissue Score Interpretation Score Interpretation Articular cartilage 30 Minutes 0.4 Non-irritant 1.0 Non-irritant 24 Hours 0.3 Non-irritant 0.3 Non-irritant 7 Days -0.3 Non-irritant 3.5 Slight irritant Mesentery 30 Minutes 1.7 Non-irritant 1.4 Non-irritant 24 Hours 1.3 Non-irritant 2.6 Non-irritant 7 Days 1.0 Non-irritant 3.2 Slight irritant Cranial dura mater 30 Minutes 0.0 Non-irritant 0.5 Non-irritant 24 Hours -1.0 Non-irritant 1.4 Non-irritant 7 Days 0.0 Non-irritant 6.1 Slight irritant Pericardium 30 Minutes 1.0 Non-irritant -0.1 Non-irritant 24 Hours -0.5 Non-irritant 6.3 Slight irritant 7 Days 1.0 Non-irritant 13.7 Moderate irritant Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6843131","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":489248073,"identity":"4de412e6-cfb4-42a0-b848-6593cbeb362c","order_by":0,"name":"Farideh Najafi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDElEQVRIie2PoU7EQBCGp0GcWVLbxyhmMU37IJjdNOkpCASDqNgaeIUTF+4JSDiDnssmPVOobQKiNVUnikMQwmxPnGqLJLn9zE42/7f/LIDF8g+ZKQBkgDQidMIPaHAyHFMYHhRnIa4To6hJBfYKOAvodH87rsxeG9zdfVy5mW5U7Zfh04OmljS4GFTY3N8si/bWw/xMCf89fikkKXlyqQaUCBLQp/eaYnheG4UjzY7SgwpzW1J+tFzh9pNa3mJeNhOKZ1qUls9YmMUw5NVUi9fCZplrucbihpRY8IpaxMhfmJucdLtUy8dqu86+vsOIl/Om7tJgUDngYX/IPikm4wZ3/2r0p7DFYrEcFb85CXU8DMkBCgAAAABJRU5ErkJggg==","orcid":"","institution":"Northside Hospital Forsyth","correspondingAuthor":true,"prefix":"","firstName":"Farideh","middleName":"","lastName":"Najafi","suffix":""},{"id":489248075,"identity":"e3857fa3-dbff-47b8-98e0-34494a3b8458","order_by":1,"name":"Jon E. Minter","email":"","orcid":"","institution":"Northside Hospital Forsyth","correspondingAuthor":false,"prefix":"","firstName":"Jon","middleName":"E.","lastName":"Minter","suffix":""}],"badges":[],"createdAt":"2025-06-07 13:38:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6843131/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6843131/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":87574868,"identity":"9f3a44dd-9384-4d35-b6e2-d3c9b14b5489","added_by":"auto","created_at":"2025-07-25 11:33:49","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1171525,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSurgical Exposure of Tissues for Irrigation Procedure\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e(A) Articular Cartilage: Exposure of the femoral condyle of the knee joint via a medial parapatellar approach.\u003cbr\u003e\n(B) Mesentery: Exposure of the mesenteric tissue through a midline laparotomy.\u003cbr\u003e\n(C) Cranial Dura Mater: Midline scalp incision and craniotomy for exposure of the dura mater.\u003cbr\u003e\n(D) Pericardium: Exposure of the pericardial sac through a left thoracotomy.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6843131/v1/0beeb9ec49a7abdd265e0810.png"},{"id":89809677,"identity":"678e2de7-e75d-4488-9d6f-46bb3415c77c","added_by":"auto","created_at":"2025-08-25 09:47:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2252157,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6843131/v1/7a067c73-39eb-4778-bba7-77a4c0548642.pdf"},{"id":87574871,"identity":"d30b3d37-e1fc-40a5-a362-f11089bf8e6e","added_by":"auto","created_at":"2025-07-25 11:33:49","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":71003,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryTables.docx","url":"https://assets-eu.researchsquare.com/files/rs-6843131/v1/c0dce0cee96e73664eb86af2.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Acute Local Irritation Potential of a Novel Citrate-Based Irrigation Solution for Surgical Procedures: An In Situ Evaluation in a Rabbit Model","fulltext":[{"header":"Introduction","content":"\u003cp\u003ePostoperative infections are among the most common and costly complications following surgical procedures. Surgical site infections (SSIs) occur in approximately 0.5\u0026ndash;3% of patients undergoing inpatient surgery in the United States, accounting for about 160,000 to 300,000 cases annually. These infections not only increase patient morbidity and mortality but also impose a significant financial burden on the healthcare system, with estimated annual costs ranging from \u003cspan\u003e$\u003c/span\u003e3.5\u0026nbsp;billion to \u003cspan\u003e$\u003c/span\u003e10\u0026nbsp;billion [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eA critical factor in the development of SSIs is the formation of bacterial biofilms on surgical sites and implanted materials. Biofilms are complex communities of microorganisms encased within a self-produced extracellular polymeric substance, which confers protection against host immune responses and increases resistance to antimicrobial agents by up to 1,000-fold compared to planktonic bacteria [\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. \u003cem\u003eStaphylococcus aureus\u003c/em\u003e, a common skin commensal, is frequently implicated in SSIs due to its ability to rapidly form biofilms and evade immune detection [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eTraditional intraoperative irrigation solutions, such as normal saline, have limited efficacy in disrupting biofilms and eliminating planktonic bacteria. Various agents, including povidone-iodine (PI) and chlorhexidine gluconate (CHG), have been utilized to enhance antimicrobial activity. However, these solutions often exhibit cytotoxic effects on host tissues, including chondrocytes, osteoblasts, and fibroblasts, necessitating their removal through additional rinsing, which may diminish their residual antimicrobial effects [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe ideal irrigation solution should effectively eradicate planktonic bacteria and disrupt biofilms while minimizing cytotoxicity to host tissues and maintaining a persistent antimicrobial effect without the need for rinsing [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. A novel citrate-based irrigation solution, XPerience\u0026trade; (XP) (Next Science LLC, Jacksonville, FL), has recently been introduced. This nontoxic, no-rinse antimicrobial surgical wash has been cleared by the United States Food and Drug Administration. It contains citric acid, sodium citrate, and sodium lauryl sulfate. Citric acid chelates metal ions from the biofilm matrix, disrupting its structural integrity, while sodium lauryl sulfate acts as an antimicrobial surfactant that reduces surface tension and lyses bacterial cells [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eWhile the antimicrobial properties of citrate-based irrigation solutions are promising [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], their safety profile concerning local tissue irritation remains to be thoroughly evaluated. Understanding the potential for acute local irritation is crucial, as it may impact post-operative healing and patient outcomes. Animal models, particularly rabbits, offer a valuable means to assess tissue responses due to their physiological similarities to humans in terms of tissue healing processes [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe purpose of this study was to evaluate the acute local irritation potential of a novel citrate-based irrigation solution when applied to various rabbit tissues in situ, including articular cartilage, cranial dura mater, mesentery, and pericardium. By comparing histological responses at multiple time points to those of a control solution (3% hypertonic saline) and na\u0026iuml;ve tissues, we aimed to determine the safety of this solution for intraoperative use without causing adverse local tissue responses.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e\u003cem\u003eStudy Design\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eBetween September 28, 2018, and February 11, 2019, an in vivo study was conducted using adult rabbits to evaluate the acute local irritation potential of a novel citrate-based irrigation solution compared to a control solution (3% hypertonic saline). The study protocol was approved by the Institutional Animal Care and Use Committee (IACUC) and adhered to the guidelines set forth by the National Institutes of Health for the care and use of laboratory animals.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eTest and Control Solutions\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe test solution was a laboratory-prepared formulation of a citrate-based irrigation solution containing 32.5 g/L citric acid, 31.3 g/L sodium citrate, and 1.0 g/L sodium lauryl sulfate in water. The control solution was a 3% hypertonic saline solution.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAnimal Allocation\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eFifty-eight male New Zealand White rabbits (Oryctolagus cuniculus), approximately 15 to 16 weeks of age and weighing between 3.1 and 4.1 kg at study start, were used. Animals were acclimated for at least five days prior to the study under standard laboratory conditions, including a 12-hour light/dark cycle, temperature of 20\u0026ndash;22\u0026deg;C, and relative humidity of 30\u0026ndash;70%. They were individually housed with ad libitum access to certified commercial feed and potable water. Animals were randomly assigned to two groups: test-treated group and control-treated group. Each group was further subdivided based on the time points for tissue evaluation: 30 minutes, 24 hours, and 7 days post-irrigation, with six or eight animals per subgroup (Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSurgical Procedure\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe animals were anesthetized using a standard protocol and surgical sites were prepared aseptically. Four tissues were surgically exposed in each animal (Figure 1):\u003c/p\u003e\n\u003col start=\"1\" type=\"1\"\u003e\n \u003cli\u003eArticular Cartilage: The knee joint was accessed via a medial parapatellar approach to expose the femoral condyle.\u003c/li\u003e\n \u003cli\u003eMesentery: A midline laparotomy was conducted to access the mesenteric tissue.\u003c/li\u003e\n \u003cli\u003eCranial Dura Mater: A midline scalp incision was made, and a craniotomy was performed to expose the dura mater.\u003c/li\u003e\n \u003cli\u003ePericardium: A left thoracotomy was performed to expose the pericardial sac.\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003e\u003cem\u003eIrrigation Procedure\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eEach exposed tissue site was irrigated with 20 mL of either the test or control solution using a 60 mL syringe to flush at a rate of approximately 2.5 mL/second. The solution was applied directly to the tissue surfaces for a duration of 10\u0026ndash;11 minutes to simulate extended intraoperative exposure. After exposure, the solution was removed by blotting with sterile gauze without rinsing the tissue. Muscle and skin layers were then surgically closed.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePostoperative Care\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNon-survival animals were euthanized approximately 30 minutes after irrigation. Survival animals designated for 24-hour and 7-day evaluations were recovered from anesthesia and returned to standard housing. Postoperative analgesia was provided as needed. Animals were monitored postoperatively for any signs of distress, complications, or adverse reactions. Body weights were recorded prior to surgery and at termination. For animals in the 7-day group, body temperatures were monitored daily using microchip transponders. Any temperatures outside the normal range (100.0\u0026ndash;104.0\u0026deg;F) were verified with a second reading, and the study director and veterinarian were notified if abnormalities persisted.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eNecropsy and Tissue Harvesting\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAt scheduled time points (30 minutes, 24 hours, and 7 days post-irrigation), animals were euthanized using an intravenous overdose of sodium pentobarbital. A necropsy was performed, including examination of external body surfaces, all orifices, cranial cavity and contents, thoracic cavity. Treatment sites and corresponding na\u0026iuml;ve tissues were collected and immersion-fixed in 10% neutral buffered formalin (Table 2).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eHistological Evaluation\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eFixed tissues were processed using standard histology techniques, including paraffin embedding, sectioning, and staining with hematoxylin and eosin. A board-certified veterinary pathologist, blinded to the treatment groups, conducted the histopathological evaluations. Local irritation was assessed according to ISO 10993-6 (2016) guidelines. An Irritant Rank Score was calculated using the formula:\u003c/p\u003e\n\u003cp\u003eIrritant Rank Score=Test Article Group Average Score\u0026minus;Control Article Group Average Score\u003c/p\u003e\n\u003cp\u003eNegative values were treated as zero. The level of irritation was categorized as:\u003c/p\u003e\n\u003cul type=\"disc\"\u003e\n \u003cli\u003eNon-irritant: 0.0 to 2.9\u003c/li\u003e\n \u003cli\u003eSlight irritant: 3.0 to 8.9\u003c/li\u003e\n \u003cli\u003eModerate irritant: 9.0 to 15.0\u003c/li\u003e\n \u003cli\u003eSevere irritant: \u0026gt;15\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eHistopathological assessment included acute inflammation (polymorphonuclear cells), chronic inflammation (lymphocytes and macrophages), necrosis, neovascularization, fibrosis, traumatic myofiber changes, bone formation, soft tissue mineralization, subacute/chronic hemorrhage, foreign body reaction, and fibrous band thickness (Table 3).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStatistical Analysis\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eData were analyzed descriptively to assess the distribution within the study groups. Continuous variables are reported as mean \u0026plusmn; standard deviation (SD), while categorical variables are presented as frequency (percentage).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cem\u003eAdministration of Test and Control Articles\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eBoth test and control articles were administered without complication. During the first application of the test solution (Group 2, articular cartilage and mesentery irrigation), brown staining was observed around these tissue sites post-irrigation, which was an expected observation due to erythrocyte crenation and associated debris.\u003c/p\u003e\n\n\u003cp\u003e\u003cem\u003eMortality and General Health Observations\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAll animals remained healthy throughout the study duration and survived until their scheduled termination at approximately 30 minutes, 24 hours, or 7 days post-irrigation. Daily observations indicated no adverse events attributable to the test or control article exposure. Only one animal required veterinary monitoring for an elevated body temperature (refer to \u003cem\u003eBody Temperature Monitoring\u003c/em\u003e), which resolved without intervention.\u003c/p\u003e\n\n\u003cp\u003e\u003cem\u003eBody Weight Changes\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eMean body weights at pre-surgery and termination are summarized in Table 4. Changes in body weight during the 7-day observation period were attributed to the surgical procedures rather than exposure to the test or control articles. \u003c/p\u003e\n\u003cul type=\"disc\"\u003e\n\u003cli\u003eArticular Cartilage and Mesentery Exposure: The majority (5 out of 6; 83%) of animals undergoing exposure of the knee joint (articular cartilage) and abdominal cavity (mesentery) lost weight during the in-life phase. Weight loss ranged from 0.1 to 0.5 kg.\u003c/li\u003e\n\u003cli\u003eCranial Dura Mater Exposure: All animals (6 out of 6; 100%) maintained or gained body weight during the 7-day in-life phase. Weight gain ranged from 0.0 to 0.2 kg.\u003c/li\u003e\n\u003cli\u003ePericardium Exposure: All animals (8 out of 8; 100%) maintained or lost body weight during the 7-day in-life phase. Weight loss ranged from 0.0 to 0.3 kg.\u003c/li\u003e\n\u003c/ul\u003e\n\n\u003cp\u003e\u003cem\u003eBody Temperature Monitoring\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eBody temperatures remained within the physiological range (100.0\u0026ndash;104.0\u0026deg;F) with mean values between 101.1 and 103.9\u0026deg;F (Table 5). Minor fluctuations outside the normal range occurred in individual animals but were neither clinically significant nor treatment-related:\u003c/p\u003e\n\u003cul type=\"disc\"\u003e\n\u003cli\u003eHypothermia: One animal in Group 5 recorded 98.5\u0026deg;F on Day 1 but normalized by Day 2 without clinical concerns.\u003c/li\u003e\n\u003cli\u003eHyperthermia: \u003cul type=\"circle\"\u003e\n\u003cli\u003eOne animal in Group 5 reached 105.8\u0026deg;F on Day 1, received veterinary observation, and normalized by Day 2.\u003c/li\u003e\n\u003cli\u003eOne animal in Group 1 recorded 104.6\u0026deg;F on Day 4, with subsequent fluctuations remaining near normal.\u003c/li\u003e\n\u003cli\u003eA final animal in Group 3 reached 104.3\u0026deg;F on Day 7 (termination day), requiring no further action.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cem\u003eGross Necropsy Findings\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAbnormalities were identified in both test and control article-treated animals across various treatment sites. Detailed findings for individual animals are available in Supplementary Tables 1\u0026ndash;3.\u003c/p\u003e\n\u003cul class=\"decimal_type\"\u003e\n\u003cli\u003eArticular Cartilage and Mesentery\u003c/li\u003e\n\u003cli\u003eMinutes Post-Irrigation: All animals showed macroscopically normal tissues.\u003c/li\u003e\n\u003cli\u003eHours Post-Test Article Irrigation: One animal exhibited brown granular material in the abdominal cavity and congested intestinal vasculature.\u003c/li\u003e\n\u003cli\u003eDays Post-Irrigation: Discoloration was observed on the lateral side of the knee in most animals, attributed to the surgical procedure rather than treatment with the test or control article.\u003c/li\u003e\n\u003cli\u003eCranial Dura Mater\u003c/li\u003e\n\u003cli\u003eMinutes Post-Irrigation: The dura mater appeared normal in all animals.\u003c/li\u003e\n\u003cli\u003eHours Post-Test Article Irrigation: A blood clot was observed at the treatment site in one test-treated animal, attributed to a procedural complication (i.e., during craniotomy, hemorrhage associated with the central cerebral vasculature required the application of hemostatic gauze to the periphery of the defect).\u003c/li\u003e\n\u003cli\u003eDays Post-Irrigation: In the test-treated cohort, one animal displayed a blood clot, and another showed extensive bruising. Both findings were likely due to surgical manipulation and unrelated to the test article.\u003c/li\u003e\n\u003cli\u003ePericardium\u003c/li\u003e\n\u003cli\u003eMinutes Post-Irrigation: \u003cul\u003e\n\u003cli\u003eBrown granular discoloration was observed in 2 of 3 (66.7%) test-treated animals.\u003c/li\u003e\n\u003cli\u003eLung congestion was noted in 1 of 3 (33%) animals in both test and control-treated groups.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n\u003cli\u003eHours Post-Irrigation: Fluid accumulation in the left thoracic cavity was observed in both test and control-treated groups: \u003cul\u003e\n\u003cli\u003eControl-treated: 2 of 2 (100%) animals, with fluid volumes ranging from 2 to 12 mL.\u003c/li\u003e\n\u003cli\u003eTest-treated: 4 of 4 (100%) animals, with fluid volumes ranging from 2 to 7 mL.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n\u003cli\u003eDays Post-Irrigation: Frank blood or red fluid was present in the thoracic cavity of most control- and all test-treated animals: \u003cul\u003e\n\u003cli\u003eControl-treated: 3 of 4 (75%) animals, with volumes ranging from 3 to 10 mL.\u003c/li\u003e\n\u003cli\u003eTest-treated: All 4 animals (100%), with volumes ranging from 20 to 30 mL.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cem\u003eHistopathological Findings\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe histopathological findings are summarized below, with the detailed microscopic scores for each study group presented in Supplementary Tables 4\u0026ndash;9.\u003c/p\u003e\n\n\u003cul\u003e\n\u003cli\u003eArticular Cartilage\u003c/li\u003e\n\u003c/ul\u003e\n\u003cul type=\"disc\"\u003e\n \u003cul type=\"circle\"\u003e\n\u003cli\u003eMinutes Post-Irrigation: Minimal polymorphonuclear cells were present in both the test- and control-treated sites. No significant differences were observed compared to na\u0026iuml;ve tissue.\u003c/li\u003e\n\u003cli\u003eHours Post-Irrigation: Slight increase in polymorphonuclear cells in test-treated sites compared to na\u0026iuml;ve tissue, resulting in a slight irritant ranking. Control-treated sites showed similar responses.\u003c/li\u003e\n\u003cli\u003eDays Post-Irrigation: Tissue responses were similar between the test- and control-treated sites, with mild chronic inflammation and neovascularization attributed to surgical access.\u003c/li\u003e\n \u003c/ul\u003e\n\u003c/ul\u003e\n\n\u003cul\u003e\n\u003cli\u003eCranial Dura Mater\u003c/li\u003e\n\u003cli\u003eMinutes Post-Irrigation: No significant inflammation or tissue reaction in test- or control-treated sites compared to na\u0026iuml;ve tissue.\u003c/li\u003e\n\u003cli\u003eHours Post-Irrigation: Slight increases in polymorphonuclear cells in both groups, with test-treated sites showing minimal differences compared to na\u0026iuml;ve tissue.\u003c/li\u003e\n\u003cli\u003eDays Post-Irrigation: Mild fibrosis observed in test-treated sites, resulting in a slight irritant ranking compared to na\u0026iuml;ve tissue.\u003c/li\u003e\n\u003c/ul\u003e\n\n\u003cul\u003e\n\u003cli\u003eMesentery\u003c/li\u003e\n\u003cli\u003eMinutes Post-Irrigation: Minimal inflammatory response in both test- and control-treated sites, comparable to na\u0026iuml;ve tissue.\u003c/li\u003e\n\u003cli\u003eHours Post-Irrigation: Slight increase in polymorphonuclear cells and neovascularization in test-treated sites compared to na\u0026iuml;ve tissue, resulting in a slight irritant ranking.\u003c/li\u003e\n\u003cli\u003eDays Post-Irrigation: Mild increases in fibrosis and neovascularization in both groups, attributed to healing processes.\u003c/li\u003e\n\u003c/ul\u003e\n\n\u003cul\u003e\n\u003cli\u003ePericardium\u003c/li\u003e\n\u003cli\u003eMinutes Post-Irrigation: Minimal inflammatory infiltrates in test-treated sites, comparable to control-treated and na\u0026iuml;ve tissues.\u003c/li\u003e\n\u003cli\u003eHours Post-Irrigation: Increased polymorphonuclear cells in test-treated sites compared to na\u0026iuml;ve tissue, resulting in a slight irritant ranking.\u003c/li\u003e\n\u003cli\u003eDays Post- Irrigation: Moderate levels of macrophages and polymorphonuclear cells in test-treated sites compared to na\u0026iuml;ve tissue, resulting in a moderate irritant ranking.\u003c/li\u003e\n\u003c/ul\u003e\n\n\u003cp\u003e\u003cem\u003eIrritation Rankings\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eIrritant Rank Scores for test-treated tissues compared to control article-treated or na\u0026iuml;ve tissues are shown in Table 6. The derivation and interpretation of these scores for each irrigated site are detailed in Supplementary Tables 10\u0026ndash;13.\u003c/p\u003e\n\n\u003cul type=\"disc\"\u003e\n\u003cli\u003eTest- vs. Control-Treated Tissues: The test solution was classified as non-irritating across all tissues and time points when compared to control-treated tissues. The Irritant Rank Scores ranged from -0.5 to 1.7, well below the slight irritant threshold of 3.0.\u003c/li\u003e\n\u003c/ul\u003e\n\n\u003cul type=\"disc\"\u003e\n\u003cli\u003eTest-Treated Tissues vs. Na\u0026iuml;ve Tissues:\u003cul type=\"circle\"\u003e\n\u003cli\u003eArticular Cartilage, Mesentery, Cranial Dura Mater: \u003cul type=\"square\"\u003e\n\u003cli\u003eNon-irritant at 30 Minutes Post-Irrigation and 24 Hours Post-Irrigation\u003c/li\u003e\n\u003cli\u003eSlight irritant at 7 Days Post-Irrigation: articular cartilage (score of 3.5), mesentery (score of 3.2), and cranial dura mater (score of 6.1).\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n\u003cli\u003ePericardium: \u003cul type=\"square\"\u003e\n\u003cli\u003eNon-irritant at 30 Minutes Post-Irrigation\u003c/li\u003e\n\u003cli\u003eSlight irritant at 24 Hours Post-Irrigation.\u003c/li\u003e\n\u003cli\u003eModerate irritant at 7 Days Post-Irrigation.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n\u003c/ul\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe present study evaluated the acute local irritation potential of a novel citrate-based irrigation solution when applied to rabbit tissues in situ, including articular cartilage, cranial dura mater, mesentery, and pericardium. The findings demonstrated that the test solution was a non-irritant compared to the control solution (3% hypertonic saline) across all tissues at all evaluated time points. When compared to na\u0026iuml;ve tissues, the test solution was classified as a slight irritant in some tissues at certain time points.\u003c/p\u003e\u003cp\u003eOur results align with previous in vitro and clinical studies suggesting that citrate-based irrigation solutions exhibit minimal cytotoxicity and are safe for intraoperative use without the need for rinsing [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Bashyal et al. reported that these solutions effectively reduced planktonic bacteria and disrupted biofilm formation without causing significant harm to host tissues [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. This is particularly important given the critical role of biofilms in SSIs and the need for irrigation solutions that are both antimicrobial and biocompatible [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe test solution evaluated in this study is composed of citric acid, sodium citrate, and sodium lauryl sulfate. Citric acid functions by binding metal ions within the biofilm matrix, thereby weakening its structure, whereas sodium lauryl sulfate serves as an antimicrobial surfactant that lowers surface tension and disrupts bacterial cell membranes [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Preliminary in vitro studies have demonstrated the efficacy of citrate-based irrigation solutions in reducing biofilm burden of multiple bacterial strains, including Staphylococcus, Pseudomonas, Cutibacterium, and Escherichia coli, with reductions of 4-log to 6-log compared to less than 1-log reductions observed with traditional solutions like PI and CHG [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Moreover, these solutions have shown minimal cytotoxicity, potentially allowing for extended tissue exposure and a sustained antimicrobial effect without the need for rinsing [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe slight irritation we observed in some tissues when compared to na\u0026iuml;ve controls is likely a result of the surgical manipulation inherent in the experimental procedures. Similar observations have been made in studies where surgical access alone can induce inflammatory responses, independent of the test articles used [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. For instance, increases in tissue inflammation, neovascularization, and fibrosis are expected physiological responses to surgical interventions and are not necessarily indicative of a deleterious effect of the irrigation solution [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eImportantly, the study found no evidence that the test solution caused more tissue response than the control solution in any of the evaluated tissues. In the articular cartilage, with the possible exception of a transient increase in polymorphonuclear cells at 24 hours post-irrigation, tissue responses were comparable between the test and control treatment. Similar observations were made for the mesentery and cranial dura mater, where any slight increases in inflammatory markers were attributed to surgical access rather than the irrigation solution.\u003c/p\u003e\u003cp\u003eIn the pericardium, while the test solution was classified as a moderate irritant compared to na\u0026iuml;ve tissue at 7 days post-irrigation, this response might also be related to the surgical procedure. Given the anatomical proximity of the pericardium to the lungs and thorax, and the volume of lavage solution used, these adjacent areas were likewise exposed to the irrigation solutions [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. This observation may suggest that citrate-based irrigation solutions could be more irritating to these tissues than control solutions, potentially contributing to effusion and fibrosis. However, the observed changes could also be attributed to differences in hemostasis and fluid absorption affecting postoperative healing [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eHowever, we acknowledge that the current study\u0026rsquo;s control design, which employed 3% hypertonic saline, does not fully isolate the effects of surgical trauma from those of the irrigation solution. The absence of an additional control group\u0026mdash;such as an isotonic saline irrigation\u0026mdash;limits the capacity to conclusively differentiate inflammation due to surgery versus that caused by the test solution. This methodological limitation is consistent with critiques in the literature emphasizing the importance of sophisticated controls to parse out confounding variables in biocompatibility studies [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe findings from this animal model provide preliminary evidence supporting the potential safe use of the citrate-based irrigation solution in surgical settings. The solution demonstrated a generally non-irritating profile and has documented antimicrobial properties, positioning it as a promising irrigation option for reducing SSIs without compromising host tissue integrity [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Traditional irrigation solutions such as PI and CHG have proven antimicrobial effects but are also known for their cytotoxicity to host tissues, often requiring removal after use [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. The ability of a citrate-based irrigation solution to remain at the surgical site without rinsing may offer advantages for prolonged antimicrobial activity and streamlined surgical protocols; however, further clinical studies are necessary to fully confirm its safety and efficacy in clinical practice.\u003c/p\u003e\u003cdiv id=\"Sec21\" class=\"Section2\"\u003e\u003ch2\u003eLimitations\u003c/h2\u003e\u003cp\u003eWhile this study provides valuable insights into the acute local irritation potential of a citrate-based irrigation solution, several limitations should be acknowledged. First, as an animal model, the results may not directly translate to human clinical scenarios due to physiological differences between species. Rabbit tissues may respond differently to irrigation solutions compared to human tissues [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eSecond, the choice of control solution, 3% hypertonic saline, may not represent the most clinically relevant comparison. Solutions commonly used in clinical practice, such as normal saline, povidone-iodine PI, or CHG, might have provided more clinically relevant comparisons. The use of a more standard control would have helped contextualize the findings in the broader scope of orthopedic surgery and irrigation practices.\u003c/p\u003e\u003cp\u003eThird, the sample size in this study was relatively small, particularly with the division of animals across multiple tissue sites and time points. This limitation may affect the statistical power of the results and the generalizability of the findings. Larger studies with more animals per subgroup are needed to strengthen the reliability of the conclusions.\u003c/p\u003e\u003cp\u003eAdditionally, the study focused on acute local irritation over a 7-day period. Long-term effects of the irrigation solution on tissue healing and function were not assessed. Future studies should consider longer follow-up periods to evaluate any delayed or chronic tissue responses that could be relevant for post-operative recovery.\u003c/p\u003e\u003cp\u003eMoreover, while the study simulated intraoperative conditions to some extent, the experimental setup cannot fully replicate the complexities of the surgical environment. Factors such as blood flow, the presence of pathogens, and patient comorbidities were not considered, and these elements may influence the tissue response to irrigation solutions in real-world clinical settings.\u003c/p\u003e\u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eUnder the conditions of this study, the novel citrate-based irrigation solution demonstrated a generally non-irritating profile when applied to rabbit articular cartilage, cranial dura mater, mesentery, and pericardium tissues in situ. However, when compared to na\u0026iuml;ve tissues, slight to moderate irritation was observed in some tissues. While these tissue responses were attributed to surgical procedures, the potential contribution of the irrigation solution cannot be entirely excluded.\u003c/p\u003e\u003cp\u003eThese findings suggest that the solution may be a safe irrigation option with minimal acute local irritation potential, supporting its potential use in surgical settings without the need for rinsing. Additionally, its ability to disrupt biofilms and reduce planktonic bacteria without causing significant harm to host tissues addresses a key need in preventing SSIs.\u003c/p\u003e\u003cp\u003eHowever, further studies, including clinical trials and long-term follow-ups, are needed to confirm the safety and efficacy of this solution in human applications. Future research should aim to validate these findings, assess its role in reducing infection rates, and evaluate its long-term effects on tissue healing and function.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eSSIs, Surgical Site Infections; PI, Povidone-iodine; CHG, Chlorhexidine gluconate; IACUC, Institutional Animal Care and Use Committee; SD, Standard Deviation\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cem\u003eEthics approval and consent to participate\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe study protocol was approved by the Institutional Animal Care and Use Committee (IACUC) and adhered to the guidelines set forth by the National Institutes of Health for the care and use of laboratory animals. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConsent for publication\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAvailability of data and materials\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eData is provided within the manuscript and supplementary information files.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCompeting Interests\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eFunding\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThis study was sponsored by Next Science, LLC (10550 Deerwood Park Boulevard, Suite 300, Jacksonville, FL 32256, USA).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAuthors\u0026apos; contributions\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eFN, MD \u0026ndash; Conceptualization, Study Design, Ethics Approval \u0026amp; Compliance, Investigation, Data Curation, Data Analysis, Manuscript Writing \u0026ndash; Original Draft, Manuscript Writing \u0026ndash; Review \u0026amp; Editing, Manuscript Submission, Project Administration.\u003c/p\u003e\n\u003cp\u003eJM, DO \u0026ndash; Conceptualization, Supervision, Manuscript Writing \u0026ndash; Review \u0026amp; Editing, Critical Revision, Visualization, Resources, Validation.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAcknowledgements\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eWe gratefully acknowledge the laboratory staff for their invaluable assistance with animal care and histological processing.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col start=\"1\" type=\"1\"\u003e\n\u003cli\u003eShambhu S, Gordon AS, Liu Y, Pany M, Padula WV, Pronovost PJ, et al. The Burden of Health Care Utilization, Cost, and Mortality Associated with Select Surgical Site Infections. The Joint Commission Journal on Quality and Patient Safety 2024;50:857\u0026ndash;66. https://doi.org/10.1016/j.jcjq.2024.08.005.\u003c/li\u003e\n\u003cli\u003eZabaglo M, Leslie SW, Sharman T. Postoperative Wound Infections. StatPearls, Treasure Island (FL): StatPearls Publishing; 2025. \u003c/li\u003e\n\u003cli\u003eGonz\u0026aacute;lez-Alonso M, Guerra-Gonz\u0026aacute;lez A, Villar-Su\u0026aacute;rez V, Fern\u0026aacute;ndez-Castilla B, S\u0026aacute;nchez-L\u0026aacute;zaro JA. Efficacy of Different Irrigation Solutions on Bacterial Biofilm in Periprosthetic Joint Infections: A Systematic Review and Network Meta-Analysis. Life (Basel) 2025;15:568. https://doi.org/10.3390/life15040568.\u003c/li\u003e\n\u003cli\u003eParvizi J, Gehrke T, Chen AF. Proceedings of the International Consensus on Periprosthetic Joint Infection. Bone Joint J 2013;95-B:1450\u0026ndash;2. https://doi.org/10.1302/0301-620X.95B11.33135.\u003c/li\u003e\n\u003cli\u003eSharma D, Misba L, Khan AU. Antibiotics versus biofilm: an emerging battleground in microbial communities. Antimicrobial Resistance \u0026amp; Infection Control 2019;8:76. https://doi.org/10.1186/s13756-019-0533-3.\u003c/li\u003e\n\u003cli\u003eArciola CR, Campoccia D, Speziale P, Montanaro L, Costerton JW. Biofilm formation in Staphylococcus implant infections. A review of molecular mechanisms and implications for biofilm-resistant materials. Biomaterials 2012;33:5967\u0026ndash;82. https://doi.org/10.1016/j.biomaterials.2012.05.031.\u003c/li\u003e\n\u003cli\u003eBrown NM, et al. Dilute betadine lavage before closure for the prevention of acute postoperative deep periprosthetic joint infection. \u003cem\u003eJ Arthroplasty\u003c/em\u003e. 2012;27(1):27-30.\u003c/li\u003e\n\u003cli\u003eChowdary PB, et al. The effect of dilute betadine lavage on wound healing and infection rates in orthopedic surgery. \u003cem\u003eJ Clin Orthop Trauma\u003c/em\u003e. 2020;11(2):S256-S260.\u003c/li\u003e\n\u003cli\u003eChao CA, Khilnani TK, Jo S, Shenoy A, Bostrom MPG, Carli AV. Not All Antiseptic Solutions Are Equivalent in Removing Biofilm: A Comparison Across Different Orthopaedic Surfaces. J Bone Joint Surg Am 2025;107:127\u0026ndash;33. https://doi.org/10.2106/JBJS.23.01118.\u003c/li\u003e\n\u003cli\u003eTarabichi M, Parvizi J. Strategies to prevent periprosthetic joint infection: a comprehensive evidence-based approach. \u003cem\u003eJ Am Acad Orthop Surg\u003c/em\u003e. 2023;31(1):e1-e12.\u003c/li\u003e\n\u003cli\u003eBashyal RK, Mathew M, Bowen E, James GA, Stulberg SD. A Novel Irrigant to Eliminate Planktonic Bacteria and Eradicate Biofilm Superstructure With Persistent Effect During Total Hip Arthroplasty. J Arthroplasty 2022;37:S647\u0026ndash;52. https://doi.org/10.1016/j.arth.2022.01.045.\u003c/li\u003e\n\u003cli\u003eVald\u0026eacute;s DA, Minter JE. Clinical use and applications of a citrate-based antiseptic lavage for the prevention and treatment of PJI. Front Med 2024;11. https://doi.org/10.3389/fmed.2024.1397192.\u003c/li\u003e\n\u003cli\u003eVatti L, Gopinath R, Heshmat C, Lariosa S, Rabbitt S, Bashyal R. The Use of a Novel Surgical Irrigant May Be Associated with Decreased Incidence of Surgical Site Infections. J Orthopaedic Experience \u0026amp; Innovation 2024;5. https://doi.org/10.60118/001c.121295\u003c/li\u003e\n\u003cli\u003eWilliams M, Harris RM. Efficacy of a Novel Intraoperative Surgical Irrigant in Preventing Periprosthetic Joint Infections in Primary Knee, Hip, and Shoulder Arthroplasties: A Retrospective Analysis. Orthop Surg 2024;16:1277\u0026ndash;83. https://doi.org/10.1111/os.14052.\u003c/li\u003e\n\u003cli\u003eZeng M, Wang Y, Liu F, Long J, Yang H. Rabbit Models for Infectious Diseases Caused by Staphylococcus aureus. Microbiology Research 2025;16:76. https://doi.org/10.3390/microbiolres16040076.\u003c/li\u003e\n\u003cli\u003eGaur G, Predtechenskaya M, Voyich JM, James G, Stewart PS, Borgogna TR. Assessing the Effects of Surgical Irrigation Solutions on Human Neutrophil Interactions with Nascent Staphylococcus aureus Biofilms. Microorganisms 2024;12:1951. https://doi.org/10.3390/microorganisms12101951.\u003c/li\u003e\n\u003cli\u003eChao CA, Khilnani TK, Jo S, Shenoy A, Bostrom MPG, Carli AV. Not All Antiseptic Solutions Are Equivalent in Removing Biofilm: A Comparison Across Different Orthopaedic Surfaces. J Bone Joint Surg Am 2025;107:127\u0026ndash;33. https://doi.org/10.2106/JBJS.23.01118.\u003c/li\u003e\n\u003cli\u003eKhosravi G, Khaledi M, Abedi A, Chehr M, Heidari MM. Inflammatory Factors Before and After Orthopedic Surgery in Patients with Fractures Following Trauma. Archives of Trauma Research 2023;11:184\u0026ndash;8. https://doi.org/10.4103/atr.atr_22_22.\u003c/li\u003e\n\u003cli\u003eChovatiya R, Medzhitov R. Stress, inflammation, and defense of homeostasis. \u003cem\u003eMol Cell\u003c/em\u003e. 2014;54(2):281-288. Chovatiya R, Medzhitov R. Stress, Inflammation, and Defense of Homeostasis. Mol Cell 2014;54:281\u0026ndash;8. https://doi.org/10.1016/j.molcel.2014.03.030.\u003c/li\u003e\n\u003cli\u003eBejar D, Triki M, Abouda M, Yengui F, Melki B, Rejeb H, et al. Pleural effusions after cardiac surgery: Etiology and outcomes. European Respiratory Journal 2016;48. https://doi.org/10.1183/13993003.congress-2016.PA2528.\u003c/li\u003e\n\u003cli\u003eMoctezuma-Ramirez A, Dworaczyk D, Whitehorn J, Li K, Cardoso C de O, Elgalad A. Designing an In Vivo Preclinical Research Study. Surgeries 2023;4:544\u0026ndash;55. https://doi.org/10.3390/surgeries4040053.\u003c/li\u003e\n\u003cli\u003eBattista N, Wickline A. Beneficial effects of a novel intraoperative surgical irrigant on post-operative knee swelling and limb function in primary total knee arthroplasty. \u003cem\u003eJ Orthop\u003c/em\u003e. 2023;37:87-93.\u003c/li\u003e\n\u003cli\u003eSinger RW. Real-World Evidence of the Impact of a Novel Surgical Irrigant on Surgical Site Infections in Primary Total Knee Arthroplasty Performed at an Ambulatory Surgery Center. Surg Infect (Larchmt) 2024;25:240\u0026ndash;6. https://doi.org/10.1089/sur.2023.304.\u003c/li\u003e\n\u003cli\u003eRydell-T\u0026ouml;rm\u0026auml;nen K, Johnson JR. The Applicability of Mouse Models to the Study of Human Disease. Methods Mol Biol 2018;1940:3\u0026ndash;22. https://doi.org/10.1007/978-1-4939-9086-3_1.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1. Experimental Design and Animal Allocation Across Groups and Time Points\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 49px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGroup\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" style=\"width: 368px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdministration\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" style=\"width: 198px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNumber of Animals at Termination Time Point \u003csup\u003ea\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eArticle\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 143px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIrrigation Sites\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 109px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eExposure\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e30 Minutes\u003csup\u003e\u0026nbsp;\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e24 Hours\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e7 Days\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 49px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003eControl\u003csup\u003e\u0026nbsp;b\u003c/sup\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 143px;\"\u003e\n \u003cp\u003eArticular cartilage (right hind limb/knee joint), Mesentery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"6\" style=\"width: 109px;\"\u003e\n \u003cp\u003eDirect contact for 10\u0026ndash;11 minutes; Volume of 20 mL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 64px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 49px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003eTest\u003csup\u003e\u0026nbsp;c\u003c/sup\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 64px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 49px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003eControl\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 143px;\"\u003e\n \u003cp\u003eDura mater (cranial)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 64px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 49px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003eTest\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 64px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 49px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003eControl\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 143px;\"\u003e\n \u003cp\u003ePericardium\u003csup\u003e\u0026nbsp;d\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 64px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 49px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 112px;\"\u003e\n \u003cp\u003eTest\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 64px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 63px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u0026nbsp;\u003c/sup\u003ePost irrigation.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u003c/sup\u003e Hypertonic Saline (3%).\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ec\u0026nbsp;\u003c/sup\u003eCitrate-based solution.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ed\u0026nbsp;\u003c/sup\u003eDue to potential higher mortality associated with thoracotomy recovery, group sizes for pericardium exposure were increased to four animals.\u003cstrong\u003e\u003cbr\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2. Treated and Untreated Tissue Sites Across Experimental Groups\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 69px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGroup\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eArticle\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 232px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTreated Sites\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 237px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUntreated (Na\u0026iuml;ve) Sites\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 69px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eControl\u003csup\u003e\u0026nbsp;a\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 232px;\"\u003e\n \u003cp\u003eRight hind limb/knee joint (articular cartilage), Intestine joined to abdominal wall (mesentery)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 237px;\"\u003e\n \u003cp\u003eHeart, Lungs, and Chest wall (pericardium, myocardium, parietal pleura)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 69px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTest\u003csup\u003e\u0026nbsp;b\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 232px;\"\u003e\n \u003cp\u003eRight hind limb/knee joint (articular cartilage), Intestine joined to abdominal wall (mesentery)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 237px;\"\u003e\n \u003cp\u003eHeart, Lungs, and Chest wall (pericardium, myocardium, parietal pleura)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 69px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eControl\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 232px;\"\u003e\n \u003cp\u003eSkull (dura mater)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 237px;\"\u003e\n \u003cp\u003eRight hind limb/knee joint (articular cartilage), Intestine joined to abdominal wall (mesentery)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 69px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTest\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 232px;\"\u003e\n \u003cp\u003eSkull (dura mater)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 237px;\"\u003e\n \u003cp\u003eRight hind limb/knee joint (articular cartilage), Intestine joined to abdominal wall (mesentery)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 69px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eControl\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 232px;\"\u003e\n \u003cp\u003eHeart, Lungs, and Chest wall (pericardium, myocardium, parietal pleura)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 237px;\"\u003e\n \u003cp\u003eSkull (dura mater)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 69px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTest\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 232px;\"\u003e\n \u003cp\u003eHeart, Lungs, and Chest wall (pericardium, myocardium, parietal pleura)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 237px;\"\u003e\n \u003cp\u003eSkull (dura mater)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003e Hypertonic Saline (3%).\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u0026nbsp;\u003c/sup\u003eCitrate-based solution.\u003cstrong\u003e\u003cbr\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3. Histopathology Severity Scores (Per Irrigated Site)\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eScore 0\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eScore 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eScore 2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eScore 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eScore 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 160px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eInflammation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" style=\"width: 458px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePolymorphonuclear cells (PMNs), Lymphocytes, Plasma Cells, Eosinophils, Macrophages\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMinimal (Rare, 1\u0026ndash;5/HPF\u003csup\u003e\u0026nbsp;a\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMild (6\u0026ndash;10/HPF)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eModerate (Heavy Infiltrate)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMarked/Severe (Packed)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMultinucleated Giant Cells\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMinimal (Rare, 1\u0026ndash;2/HPF)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMild (3\u0026ndash;5/HPF)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eModerate (Heavy Infiltrate)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMarked/Severe (Sheets)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNecrosis\u003csup\u003e\u0026nbsp;b\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMinimal (Mild)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eModerate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMarked/Severe\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 160px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTissue Response\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" style=\"width: 458px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNeovascularization\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eMinimal capillary proliferation (focal, 1\u0026ndash;3 capillary buds), or small blood vessels (venules, and/or arterioles)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eGroups of 4\u0026ndash;7 capillaries with supporting fibroblastic structures\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eBroad band of capillaries with supporting structures\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eExtensive band of capillaries with supporting fibroblastic structures\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eFibrosis/Fibrous Band\u003csup\u003e\u0026nbsp;c\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eFibrous band is not formed (i.e., cellular capsule composed predominantly of inflammatory cells with little fibroplasia), or is too thin to measure\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNarrow band (\u0026lt;100 \u0026micro;m Mean Fibrous Band Thickness)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eModerately thick band (\u0026gt;100, up to 200 \u0026micro;m Mean Fibrous Band Thickness)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eThick band (\u0026gt;200, up to 300 \u0026micro;m Mean Fibrous Band Thickness)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eExtensive band (\u0026gt;300 \u0026micro;m Mean Fibrous Band Thickness)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 160px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" style=\"width: 458px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eGranuloma Formation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"8\"\u003e\n \u003cp\u003eAbsent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"8\"\u003e\n \u003cp\u003eMinimal/Slight (\u0026gt;0 up to 25% of the irrigated site field)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"8\"\u003e\n \u003cp\u003eMild (\u0026gt;25 up to 50% of the irrigated site field)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"8\"\u003e\n \u003cp\u003eModerate (\u0026gt;50 up to 75% of the irrigated site field)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"8\"\u003e\n \u003cp\u003eMarked/Severe (\u0026gt;75 up to 100% of the irrigated site field)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eTraumatic Myofiber Changes\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eFatty Infiltration\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eBone Formation \u003csup\u003ed\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eTissue Ingrowth into the Irrigated Material\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eSoft Tissue Mineralization\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eHemorrhage, subacute / chronic\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eForeign Material (other than irrigated material)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003csup\u003ea\u0026nbsp;\u003c/sup\u003eHPF = high powered field (40X), averaged over the entire irrigated site.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u0026nbsp;\u003c/sup\u003eNecrosis consists of nuclear cellular debris from degenerating inflammatory cells.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ec\u0026nbsp;\u003c/sup\u003eThe fibrous band score is derived from the average of the mean capsule thickness (in microns) for each of the irrigated sites.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ed\u0026nbsp;\u003c/sup\u003eCriteria for bone formation include the presence of one or more of the following features: cartilage, chondrocytes/chondroblasts, new bone/osteoid, osteoblasts/osteocytes, bone marrow\u003cbr\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4. Mean Body Weights at Pre-Surgery and Termination Time Points\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" width=\"480\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 122px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTimepoint- Post Irrigation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGroup\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 285px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean \u0026plusmn; SD\u003csup\u003e\u0026nbsp;a\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePrior to Implant\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTermination\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"6\" style=\"width: 122px;\"\u003e\n \u003cp\u003e30 Minutes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.4 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.4 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.5 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.5 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.6 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.5 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.7 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.7 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"6\" style=\"width: 122px;\"\u003e\n \u003cp\u003e24 Hours\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.6 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.4 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.2 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.4 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.4 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.5 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.7 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.6 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"6\" style=\"width: 122px;\"\u003e\n \u003cp\u003e7 Days\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.2 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.4 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.2 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.4 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.5 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.7 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.9 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.8 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 65px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e3.4 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 141px;\"\u003e\n \u003cp\u003e3.3 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u0026nbsp;\u003c/sup\u003eSD \u0026nbsp;= standard deviation\u003cstrong\u003e\u003cbr\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5. Daily Mean Body Temperatures (\u0026deg;F) Across Different Irrigated Sites for 7-Day Survival Animals\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" width=\"498\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 135px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSite\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTimepoint\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 255px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean \u0026plusmn; SD\u003csup\u003e\u0026nbsp;a\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl article\u003csup\u003e\u0026nbsp;b\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTest article\u003csup\u003e\u0026nbsp;c\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"7\" style=\"width: 135px;\"\u003e\n \u003cp\u003eArticular cartilage and mesentery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.4 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e103.4 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.0 \u0026plusmn; 0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e103.1 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.0 \u0026plusmn; 0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e103.3 \u0026plusmn; 0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.8 \u0026plusmn; 0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e103.3 \u0026plusmn; 0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e102.9 \u0026plusmn; 0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e103.6 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.2 \u0026plusmn; 0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e103.5 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.5 \u0026plusmn; 0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e103.7 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"7\" style=\"width: 135px;\"\u003e\n \u003cp\u003eCranial dura mater\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e102.8 \u0026plusmn; 0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e102.9 \u0026plusmn; 0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.1 \u0026plusmn; 0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e102.9 \u0026plusmn; 0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e102.3 \u0026plusmn; 0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e102.8 \u0026plusmn; 0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e102.8 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e102.5 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.0 \u0026plusmn; 1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e102.6 \u0026plusmn; 0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e102.8 \u0026plusmn; 0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e102.8 \u0026plusmn; 0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e103.9 \u0026plusmn; 0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e103.8 \u0026plusmn; 0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"7\" style=\"width: 135px;\"\u003e\n \u003cp\u003ePericardium\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e102.0 \u0026plusmn; 3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e101.3 \u0026plusmn; 1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e101.1 \u0026plusmn; 0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e101.3 \u0026plusmn; 0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e101.6 \u0026plusmn; 0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e101.3 \u0026plusmn; 0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e101.0 \u0026plusmn; 0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e100.8 \u0026plusmn; 0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e101.8 \u0026plusmn; 0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e101.7 \u0026plusmn; 0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e102.0 \u0026plusmn; 0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e101.7 \u0026plusmn; 0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eDay 7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e102.3 \u0026plusmn; 1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 123px;\"\u003e\n \u003cp\u003e102.2 \u0026plusmn; 0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u0026nbsp;\u003c/sup\u003eSD \u0026nbsp;= standard deviation\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u003c/sup\u003e Hypertonic Saline (3%).\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ec\u0026nbsp;\u003c/sup\u003eCitrate-based solution.\u003cbr\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 6. Irritant Rank Scores for Test Solution Across Different Tissue Sites and Time Points\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"1\" cellpadding=\"0\" class=\"fr-table-selection-hover\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 99px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSite\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 99px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTimepoint- Post Irrigation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" style=\"width: 376px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTissue for Comparison\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" style=\"width: 185px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl Article-Treated\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 189px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNa\u0026iuml;ve Untreated Tissue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eScore\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eInterpretation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eScore\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eInterpretation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 99px;\"\u003e\n \u003cp\u003eArticular cartilage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e30 Minutes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e24 Hours\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e7 Days\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e3.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eSlight irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 99px;\"\u003e\n \u003cp\u003eMesentery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e30 Minutes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e1.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e1.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e24 Hours\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e1.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e7 Days\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e3.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eSlight irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 99px;\"\u003e\n \u003cp\u003eCranial dura mater\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e30 Minutes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e24 Hours\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e1.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e7 Days\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e6.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eSlight irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 99px;\"\u003e\n \u003cp\u003ePericardium\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e30 Minutes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e-0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e24 Hours\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e6.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eSlight irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e7 Days\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 124px;\"\u003e\n \u003cp\u003eNon-irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 58px;\"\u003e\n \u003cp\u003e13.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 129px;\"\u003e\n \u003cp\u003eModerate irritant\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Citrate-based irrigation solution, Biofilm disruption, Tissue irritation, Rabbit in situ model, Surgical Site Infection, Postoperative infections, Surgical irrigation solution","lastPublishedDoi":"10.21203/rs.3.rs-6843131/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6843131/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Postoperative infections remain a major complication across a wide range of surgical procedures, largely due to bacterial biofilm formation. A novel citrate-based irrigation solution has shown promise in disrupting biofilms and reducing planktonic bacteria without cytotoxic effects. This study evaluates the acute local irritation potential of the solution on rabbit tissues in situ to assess its safety for intraoperative use.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Fifty-eight adult rabbits underwent surgical exposure of articular-cartilage, cranial-dura-mater, mesentery, and pericardium tissues. Tissues were irrigated with either the novel citrate-based solution or a control solution (3% hypertonic saline) for 10–11 minutes. Histopathological evaluations were conducted at 30 minutes, 24 hours, and 7 days post-irrigation to assess tissue response, including inflammation, necrosis, neovascularization, and fibrosis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The solution was classified as non-irritating compared to the control solution across all tissues and time points. When compared to naïve tissues, it was a non-irritant at 30 minutes and 24 hours post-irrigation and a slight irritant at 7 days for articular-cartilage, cranial-dura-mater, and mesentery. For the pericardium, it was a non-irritant at 30 minutes, a slight irritant at 24 hours, and a moderate irritant at 7 days.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e The novel citrate-based irrigation solution demonstrates minimal acute local irritation when applied to rabbit tissues in situ, with slight to moderate irritation observed in certain tissues at specific time points. These findings support its potential as an intraoperative irrigation solution with minimal risk for irritation, but further studies are necessary to fully assess its safety and long-term effects in clinical applications.\u003c/p\u003e","manuscriptTitle":"Acute Local Irritation Potential of a Novel Citrate-Based Irrigation Solution for Surgical Procedures: An In Situ Evaluation in a Rabbit Model","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-25 11:33:44","doi":"10.21203/rs.3.rs-6843131/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e10c68d5-02b4-402e-874e-0d6b7ff46770","owner":[],"postedDate":"July 25th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-08-25T09:39:08+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-25 11:33:44","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6843131","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6843131","identity":"rs-6843131","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}