Efficacy and Safety of Negative Pressure Aspiration in Percutaneous Nephrolithotomy for Infectious Kidney Stones: A Retrospective Study

Efficacy and Safety of Negative Pressure Aspiration in Percutaneous Nephrolithotomy for Infectious Kidney Stones: A Retrospective Study | 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 Efficacy and Safety of Negative Pressure Aspiration in Percutaneous Nephrolithotomy for Infectious Kidney Stones: A Retrospective Study Wei Chen, Hui He, Xingfa Chen, Qinzhi Long, Na Zhang, Xiang LI This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5422838/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 Percutaneous nephrolithotomy (PCNL) is the preferred treatment for large and complex infectious kidney stones but is associated with a risk of urosepsis due to elevated renal pelvic pressure. Negative pressure aspiration during PCNL may mitigate this risk by continuously evacuating irrigation fluid, stone fragments, and bacteria, thereby lowering intrarenal pressure and reducing postoperative complications. This study evaluates the safety and efficacy of PCNL with negative pressure aspiration for treating infectious kidney stones. Methods A retrospective study included 126 patients with infectious renal stones treated from October 2017 to May 2024. Among them, 57 underwent conventional mini-PCNL, and 69 received mini-PCNL with negative pressure aspiration. Demographic data and perioperative parameters, including operation time, blood loss, hospital stay, and stone clearance rate (SCR), were recorded. Blood loss was assessed by hemoglobin changes, and inflammatory responses were measured using serum IL-6 and procalcitonin (PCT) levels. Postoperative complications were classified using the Modified Clavien-Dindo Classification system. Results Negative pressure aspiration significantly improved primary SCR (79.7% vs. 59.6%) and reduced postoperative fever incidence (8.7% vs. 31.6%) compared to conventional PCNL. The incidence of urosepsis was lower (2.9% vs. 14%), and blood loss was reduced, with fewer transfusions required. Patients treated with negative pressure aspiration recovered faster, resuming normal activities in an average of 2.41 ± 1.35 days compared to 3.05 ± 1.78 days for conventional PCNL patients. The average hospital stay was shorter for patients with negative pressure aspiration (3.44 vs. 4.47 days). Conclusions Negative pressure aspiration during PCNL offers significant benefits, including improved stone clearance, reduced postoperative complications, lower infection risk, and faster recovery. This technique should be considered a preferred option for treating infectious kidney stones, demonstrating superior surgical outcomes and enhanced patient recovery compared to traditional PCNL. Negative pressure aspiration PCNL kidney stones infection Figures Figure 1 Introduction Infection stone is a broad category of kidney stones that form in response to chronic urinary tract infections (UTIs) caused by urease-producing bacteria. These bacteria, such as Proteus, Pseudomonas, and Klebsiella, break down urea into ammonia, which raises the pH of the urine (making it more alkaline). This environment promotes the formation of specific types of stones, including struvite stones, carbonate apatite stones, and ammonium acid urate stones [ 1 – 3 ]. Managing these stones is critical due to their potential to cause recurrent infections, kidney damage, and sepsis [ 4 , 5 ]. Percutaneous nephrolithotomy (PCNL) is often the preferred treatment for infectious stones because of its ability to remove large and complex stones effectively [ 6 ]. However, one of the significant risks associated with PCNL is the development of urosepsis, a severe and potentially life-threatening infection that can occur if bacteria from the urinary tract enter the bloodstream. This risk can be exacerbated by high pressure in the renal pelvis. During PCNL, irrigation fluid is used to maintain a clear surgical field and facilitate the removal of stone fragments. However, excessive irrigation or obstruction can lead to increased pressure in the renal pelvis. High renal pelvic pressure can force bacteria and endotoxins into the bloodstream, increasing the risk of urosepsis [ 7 , 8 ]. Negative pressure aspiration during PCNL offers a solution to mitigate these risks by actively managing and reducing the pressure in the renal pelvis. Negative pressure aspiration helps to continuously evacuate irrigation fluid, stone fragments, and debris, thereby preventing the build-up of high pressure within the renal pelvis. By lowering renal pelvic pressure, the risk of bacterial translocation and subsequent urosepsis is significantly reduced. This is particularly important in patients with infectious stones or a history of urinary tract infections. Continuous aspiration also ensures that stone fragments and infectious material are promptly removed from the kidney, reducing the chance of postoperative infection [ 9 – 11 ]. Typically, the negative pressure suction function is provided by standard-channel PCNL; however, miniaturized-channel PCNL may reduce the risk of kidney injury and bleeding. Mini Percutaneous Nephrolithotomy (mini-PCNL) is a minimally invasive variation of the standard PCNL procedure that utilizes smaller instruments and access tracts. When combined with negative pressure aspiration, mini-PCNL can offer additional benefits in terms of safety and efficacy, particularly for managing infectious upper urinary tract stones [ 12 – 14 ]. Materials and methods A total of 126 patients with infectious renal stones were enrolled in this retrospective study, conducted from October 2017 to May 2024. Of these patients, 57 underwent conventional mini-PCNL, while the remaining 69 underwent mini-PCNL with negative pressure aspiration. Before surgery, all patients were evaluated through routine blood and urine tests, renal function tests, coagulation profile tests, and urine cultures. For those with positive urine cultures, appropriate antibiotics were administered. Imaging examinations, including ultrasound, CT scans, or IVP, were also performed on all patients. Demographic data and perioperative parameters, such as operation time, blood loss, hospital stay, and stone clearance rate (SCR), were recorded. Blood loss was assessed by the change in hemoglobin levels between 2 hours preoperatively and 2 hours postoperatively. The levels of serum Interleukin-6 (IL-6) and procalcitonin (PCT) were measured to evaluate the inflammatory response. Postoperative complications were assessed using the modified Clavien grading system. A ureteral catheter was inserted through the urethra into the bladder and advanced into the renal pelvis. The patient was then placed in the prone position, and a thin needle was passed through the skin directly into the targeted renal calyx under ultrasound guidance. A guidewire was inserted through the needle into the kidney, establishing a pathway for subsequent dilation. After sequential dilation using fascial dilators, a 16 F nephrostomy sheath was inserted over the guidewire, creating a stable access route to the kidney. For patients undergoing mini-PCNL with the negative pressure aspiration technique, a specially designed nephrostomy sheath (Weili, China) was used, which connected to a suction apparatus. Continuous suction was applied throughout the procedure to evacuate stone fragments, irrigation fluid, and any blood from the kidney (Fig. 1 ). The nephoscope was inserted into the renal pelvis or calyx, and a holmium laser was used to break the stones into smaller fragments (Moses, Lumenis, Israel). Larger stone fragments were extracted using graspers or baskets, which were passed through the nephrostomy sheath. The negative pressure aspiration system continuously removed smaller fragments along with the irrigation fluid. Before the conclusion of the operation, a double-J stent and nephrostomy tube were placed to allow for continued drainage of urine and any remaining debris after surgery. KUB (kidney, ureter, and bladder) films combined with ultrasound were used to assess stone clearance. The nephrostomy tube was removed 1 to 4 days postoperatively, once the stones were cleared and there were no signs of infection or obstruction. The final stone clearance rate was evaluated at 3 months postoperatively. Throughout the study, statistical analysis was done using commercially available software, including the Chi-square test, two-sample independent t test, Mann-Whitney U, and Fisher’s exact test (SPSS 30. 0 version). P < 0.05 was considered significant. Results There were no significant differences in the age, gender, BMI or baseline health conditions between mini-PCNL with or without negative pressure aspiration. The stone baseline characteristics regarding the size, intensity and status of kidney stones were similar in both groups (Table 1 ). Table 1 Demographic data and status of stones Group N-PCNL (N = 69) C- PCNL (N = 57) P value Age (years) 47.51 ± 11.12 46.89 ± 13.47 P = 0.668▼ Sex ratio Male (41/69) Male (30/57) P = 0.559# BMI (kg/m2) Mean (Range) 28.15(23–38) 25.48(21–35) P = 0.13▼ Stone status Stone size (cm) 3.34 ± 1.00 3.22 ± 0.96 P = 0.519▼ Stone intensity (CT value HU) 840.59 ± 126.11 837.05 ± 154.35 P = 0.887▼ Stones in pelvis and calyceal (%) N = 27(39%) N = 25(44%) P = 0.641# Staghorn stone (%) N = 14(20%) N = 9(16%) Stone composition Struvite stones (%) N = 19 (28%) N = 11(19%) P = 0.463# Carbonate apatite stones (%) N = 46(67% N = 44(77%) Ammonium acid urate stones (%) N = 2 (3%) N = 1 (2%) N-PCNL: Percutaneous nephrolithotomy (PCNL) with Negative pressure aspiration; C-PCNL: Conventional percutaneous nephrolithotomy (PCNL) ▼P < 0.05 was considered statistical significant between the two groups by using Independent Samples t-test (SPSS 30). #P < 0.05 was considered statistical significant between the two groups by using two side chi-square test. (SPSS 30) Our data indicated that negative pressure aspiration during PCNL offered several advantages that enhanced the procedure’s safety, efficacy, and overall outcomes. The primary stone clearance rate (SCR) was significantly higher (79.7% vs. 59.6%) with the use of negative pressure suction during PCNL. Residual stones were treated with flexible ureteroscopy lithotripsy, ESWL, or a second PCNL. The final SCR remained higher with negative pressure aspiration (88.4% vs. 78.9%), although the difference was not statistically significant. Negative pressure aspiration markedly decreased the incidence of postoperative fever, defined as a body temperature higher than 38.5°C after surgery. The incidence of postoperative fever was 8.7% in the PCNL group with negative pressure aspiration, compared to 31.6% in the conventional PCNL group. Both procalcitonin (PCT) and interleukin-6 (IL-6) levels were significantly elevated after surgery, but the negative pressure suction technique notably inhibited the rise in these infection markers. Sixteen patients required escalation of antibiotic treatment due to severe postoperative infection, while only four patients needed adjustments to their initial antibiotic therapy when the negative pressure suction technique was used. Urosepsis, a severe and potentially life-threatening condition where a urinary tract infection spreads into the bloodstream causing systemic infection, occurred in only 2.9% of patients with negative pressure aspiration during PCNL, compared to 14% in the group without negative pressure suction. In the PCNL group without negative pressure aspiration, two patients were diagnosed with uroseptic shock and were transferred to the ICU for further treatment. The decrease in hemoglobin between pre- and postoperative measurements was used to assess blood loss during the operation. The data showed that the use of negative pressure aspiration significantly reduced blood loss. A total of four patients required blood transfusions, with only one of them having undergone surgery with negative pressure aspiration. Two patients eventually required selective renal artery embolization therapy due to severe arterial bleeding, and both had undergone surgery without negative pressure aspiration. Other general postoperative complications were assessed using the Modified Clavien-Dindo Classification system. The complication scores were similar between the two groups, regardless of whether negative pressure aspiration was used. The data also showed that negative pressure aspiration during PCNL helped patients return to normal activities more quickly. The average time to return to normal activity was 2.41 days for patients in the PCNL group with negative pressure aspiration, compared to 3.05 days for those undergoing traditional PCNL. The average postoperative hospital stay was 3.44 days and 4.47 days, respectively, for patients with and without negative pressure aspiration during the operation. These differences were statistically significant (Table 2 ). Table 2 The comparison of operation outcome and complications between PCNL with and without negative pressure aspiration. N-PCNL(N = 69) C-PCNL(N = 57) P value Operation time (minutes) 90.00 ± 29.32 84.74 ± 30.84 P = 0.173* Primary stone clearance (%) N = 55 (79.7%) N = 34 (59.6%) P = 0.024# Final stone clearance (%) N = 61 (88.4%) N = 45 (78.9%) P = 0.230# Postoperative hospital stay (day) 3.44 ± 1.46 4.47 ± 2.87 P = 0.011* Time of return to normal activity(day) 2.41 ± 1.35 3.05 ± 1.78 P = 0.005* Post operative fever (%) N = 6 (8.7%) N = 18 (31.6%) P = 0.003# Serum IL-6 (pg/ml) 51.20 ± 44.67 82.35 ± 91.92 P = 0.023* Serum Pct (ng/ml) 4.14 ± 5.84 11.38 ± 18.42 P = 0.006* Escalation of antibiotic therapy (%) N = 4 (5.8%) N = 16(28.1%) P = 0.001# Urosepsis (%) N = 2 (2.9%) N = 8 (14%) P = 0.048# hemoglobin decrease, mg/dl 15.12 ± 8.19 21.82 ± 12.27 P < 0.001* Classification of complications p = 0.148# Grade 0 N = 39 N = 23 Grade I N = 26 N = 25 Grade II N = 3 N = 5 More than Grade II N = 1 N = 4 N-PCNL: percutaneous nephrolithotomy(PCNL)with negative pressure aspiration. C-PCNL: Conventional percutaneous nephrolithotomy. * P < 0.05 was considered statistical significant between the two groups by using Mann-Whitney-U test (SPSS 30). # P < 0.05 was considered statistical significant between the two groups by using two side chi-square test (SPSS 30). Discussion Compared with traditional PCNL, negative pressure aspiration during operation offers several advantages that enhance the procedure's safety, efficacy, and overall outcomes. One of the main benefits of negative pressure aspiration is its ability to maintain low intrarenal pressure [ 15 ]. Traditional PCNL can increase the pressure inside the kidney, potentially causing complications like fluid absorption or damage to kidney structures. Negative pressure suction helps to prevent this by constantly aspirating fluids and debris. Keeping a lower pressure of renal pelvis is very important to reduce the risk of bacteria and toxins being forced into the bloodstream, thereby lowering the incidence of urosepsis, a serious postoperative infection that can occur during PCNL. Our results confirmed that the incidence of urosepsis was significantly decreased for those patients by using negative pressure aspiration during operation. Studies have shown that PCNL with negative pressure aspiration is associated with a lower incidence of postoperative fever, which is often a sign of infection [ 16 , 17 ]. By minimizing fluid retention and bacterial spread during surgery, the body's inflammatory response is reduced. Our data was insistent with these literatures. Additionally, the suction technique may help lower proinflammatory markers, such as interleukin-6 (IL-6) and procalcitonin (PCT), which are elevated in response to infections. IL-6 is a key cytokine, involved in inflammation and the immune response. Infections and endotoxemia can significantly elevate IL-6 levels [ 18 ]. Lower IL-6 levels are associated with a reduced inflammatory response and fewer postoperative complications such as fever and systemic inflammatory response syndrome (SIRS) [ 19 ]. High PCT levels postoperatively indicate a systemic inflammatory response often due to infection. And lower PCT levels postoperatively suggest a lower risk of severe infections, allowing for quicker recovery and reducing the need for aggressive antibiotic treatments [ 20 , 21 ]. Our data confirmed that the elevation o IL-6 and Pct during the procedure were significantly inhibited by using suction technique. We considered that negative pressure aspiration helps maintain a lower intrarenal pressure and continuously removes infected debris, blood, and irrigation fluids, reducing the overall inflammatory response during PCNL. Studies shown that negative pressure aspiration during PCNL contributes to a better SCR by enhancing the removal of stone fragments during the procedure [ 13 , 15 , 21 ]. Our study confirmed a significant higher primary SCR by using suction technique during PCNL. Several reasons were considered to explain how it works to promote the SCR. Firstly, negative pressure aspiration is to provide continuous suction during the procedure, which helps to consistently remove stone fragments as they are being broken down. The immediate removal of fragments as they are broken by the holmium laser results in more efficient fragment evacuation, leading to a higher SCR. Secondly, consistent suction helps to prevent fragment migration during operation. In traditional PCNL, stone fragments may move around or migrate to other parts of the kidney, making them harder to remove. Negative pressure aspiration helps to keep the surgical field clear and prevents the migration of fragments, enabling the surgeon to target and remove them more easily. Thirdly, it can provide a clearer surgical field. Continuous aspiration clears blood, irrigation fluid, and debris from the surgical field, providing the surgeon with a clear view of the operative area. The enhanced visibility allows for more precise targeting and fragmentation of the stones during the procedure. Lastly, negative pressure aspiration helps to provide longer operating time for more complete clearance. Since negative pressure suction maintains low intrarenal pressure, it allows for a longer and safer operating time. Surgeons can take their time ensuring all stone fragments are removed without worrying about complications from high pressure, leading to more complete stone clearance. Negative pressure aspiration was also demonstrated to result in less blood loss compared to traditional PCNL in our study. It provides continuous suction that actively removes blood from the surgical field. Thus, the surgeon can better visualize the surgical area, leading to more precise and controlled maneuvers. This reduces inadvertent trauma to blood vessels, minimizing blood loss. Additionally, maintaining a clear surgical field allows for better identification and management of bleeding sources. Surgeons can promptly address bleeding vessels with cauterization or other hemostatic techniques, reducing overall blood loss. Another impossible reason of negative pressure aspiration can reduce bleeding is to control renal pressure during the operation. Traditional PCNL can lead to increased intrarenal pressure, which may cause more bleeding from damaged blood vessels [ 22 ]. However, negative pressure aspiration helps maintain low intrarenal pressure, reducing the likelihood of ruptured blood vessels or excessive bleeding from the kidney tissues [ 23 ]. Lower intrarenal pressure also minimizes the risk of blood and fluid leaking into surrounding tissues, further controlling blood loss. Our data showed a shorter hospital stay and quicker return to normal activities by using negative pressure aspiration compare to traditional PCNL. Negative pressure aspiration minimizes the risk of complications like infection, bleeding, and urosepsis by maintaining low intrarenal pressure and effectively removing stone fragments and bacteria. Fewer complications mean patients experience less postoperative distress, leading to a smoother and quicker recovery. Furthermore, maintaining low intrarenal pressure reduces the risk of bacterial and toxin translocation into the bloodstream, lowering the incidence of postoperative infections. Fewer infections lead to fewer complications, shorter hospital stays, and a more straightforward recovery process. As negative pressure aspiration helps reduce blood loss during the procedure, patients experience less anemia and quicker physiological recovery after surgery. This enables them to regain strength and return to normal activities sooner. Conclusion In this study, the priority of negative pressure aspiration during PCNL is highlighted as a significant advancement in the treatment of infectious kidney stones. The study demonstrates that incorporating negative pressure aspiration into PCNL improves surgical outcomes in several key areas. (1) Negative pressure aspiration leads to more effective removal of stone fragments. (2) The technique helps maintain low intrarenal pressure, significantly reducing the risk of infection, particularly urosepsis, and lowering postoperative fever rates. (3) Continuous suction allows for better control of bleeding, resulting in less intraoperative blood loss and improved surgical field visibility. (4) Due to fewer complications and less trauma during the procedure, patients experience faster recovery times, reduced inflammation, and quicker discharge from the hospital. Our study concludes that negative pressure aspiration should be considered a priority technique in PCNL, as it enhances stone clearance, minimizes complications, reduces blood loss, and improves overall patient recovery. Its integration into PCNL makes it a superior method for managing infectious kidney stones compared to conventional techniques. Declarations Author Contribution Xiang Li designed the study and drafted the main workWei Chen did participate in research work and contribute to writing portions of the content. Xingfa Chen supervise the studyQinzhi Long acquisition and analysisHui He participate in reviewing and revising the research paper Na Zhang prepared the literature review References Rodman JS. Struvite stones. Nephron . 1999;81 Suppl 1:50-9. Miano R, Germani S, Vespasiani G. 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Predictive values of the SOFA score and procalcitonin for septic shock after percutaneous nephrolithotomy. Urolithiasis . 2022;50(6):729-35. Du C, Song L, Wu X, Fan D, Zhu L, Liu S, Deng X, Liu T, Yang Z, Peng Z, et al. Suctioning minimally invasive percutaneous nephrolithotomy with a patented system is effective to treat renal staghorn calculi: a prospective multicenter study. Urol Int . 2018;101(2):143-9. Geavlete P, Multescu R, Mares C, Buzescu B, Iordache V, Geavlete B. Retrograde intrarenal surgery for lithiasis using suctioning devices: a shift in paradigm? J Clin Med . 2024;13(9):2493. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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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-5422838","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":382090909,"identity":"3fb15dea-9150-428f-bf9c-71641c4a38b3","order_by":0,"name":"Wei Chen","email":"","orcid":"","institution":"First affiliated hospital of Xi’an Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Wei","middleName":"","lastName":"Chen","suffix":""},{"id":382090910,"identity":"39e724bc-79ad-46c1-901b-89c4119195a8","order_by":1,"name":"Hui He","email":"","orcid":"","institution":"First affiliated hospital of Xi’an Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Hui","middleName":"","lastName":"He","suffix":""},{"id":382090911,"identity":"18f25ae8-c269-45f5-bd4c-1aa92ab08aa6","order_by":2,"name":"Xingfa Chen","email":"","orcid":"","institution":"First affiliated hospital of Xi’an Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Xingfa","middleName":"","lastName":"Chen","suffix":""},{"id":382090912,"identity":"2dfa4fd5-34a1-45c1-acdd-58f5d5a50aca","order_by":3,"name":"Qinzhi Long","email":"","orcid":"","institution":"First affiliated hospital of Xi’an Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Qinzhi","middleName":"","lastName":"Long","suffix":""},{"id":382090913,"identity":"4267debf-1ab3-4400-a492-e87b4c515d2c","order_by":4,"name":"Na Zhang","email":"","orcid":"","institution":"First affiliated hospital of Xi’an Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Na","middleName":"","lastName":"Zhang","suffix":""},{"id":382090914,"identity":"4426e504-6026-49fd-84c2-59659edd4c7b","order_by":5,"name":"Xiang LI","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1UlEQVRIie3PMQrCMBTG8RcepEvUNQXxDHERt1wlQegmOHYQcZB2sLp7C0fHSqFTdC641BvoJuJg7eLWZhTMf8rwfoQPwOX6zUgKwAE8IKUK53amJgwBRWlyawIfQv3rCtvPxSVL09tzLCWyUaiXFHrxWjWTc6COuy3XCdKg0Ic+cHPaNxPDRNZJuGKIeaENBcGndkQyJNFMR2hJ2IOTpPoFrIhvaLVlWW3J6IQrk7PWLV2Dx/L2WkgvTob3Rzgf9OJNM6kj0ffN2s/rXpZ3LpfL9Z+9AalMRogdvCIRAAAAAElFTkSuQmCC","orcid":"","institution":"First affiliated hospital of Xi’an Jiaotong University","correspondingAuthor":true,"prefix":"","firstName":"Xiang","middleName":"","lastName":"LI","suffix":""}],"badges":[],"createdAt":"2024-11-09 16:23:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5422838/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5422838/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":71561005,"identity":"2c1f1423-d9d8-4590-bda2-d12770ea2e36","added_by":"auto","created_at":"2024-12-16 16:56:22","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1072376,"visible":true,"origin":"","legend":"\u003cp\u003eThe application of PCNL with negative pressure aspiration.\u003c/p\u003e\n\u003cp\u003eA: Y-shaped design of the percutaneous nephoscope working sheath. Figure B: Stone collection bottle connected to the working sheath and the central vacuum system in the operating room. C: During lithotripsy, stone fragments and blood clots are suctioned out by the vacuum. D: large number of stone fragments collected in the collection bottle.\u003c/p\u003e","description":"","filename":"figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5422838/v1/ff83b869c6a0550c0dc14f2f.jpg"},{"id":82286748,"identity":"9109d536-e5c0-41a9-a8b7-127582a41881","added_by":"auto","created_at":"2025-05-08 16:31:42","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1510222,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5422838/v1/789c28bd-c2e0-47ab-b082-8b71c99cf0e3.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Efficacy and Safety of Negative Pressure Aspiration in Percutaneous Nephrolithotomy for Infectious Kidney Stones: A Retrospective Study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eInfection stone is a broad category of kidney stones that form in response to chronic urinary tract infections (UTIs) caused by urease-producing bacteria. These bacteria, such as Proteus, Pseudomonas, and Klebsiella, break down urea into ammonia, which raises the pH of the urine (making it more alkaline). This environment promotes the formation of specific types of stones, including struvite stones, carbonate apatite stones, and ammonium acid urate stones [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Managing these stones is critical due to their potential to cause recurrent infections, kidney damage, and sepsis [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Percutaneous nephrolithotomy (PCNL) is often the preferred treatment for infectious stones because of its ability to remove large and complex stones effectively [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, one of the significant risks associated with PCNL is the development of urosepsis, a severe and potentially life-threatening infection that can occur if bacteria from the urinary tract enter the bloodstream. This risk can be exacerbated by high pressure in the renal pelvis. During PCNL, irrigation fluid is used to maintain a clear surgical field and facilitate the removal of stone fragments. However, excessive irrigation or obstruction can lead to increased pressure in the renal pelvis. High renal pelvic pressure can force bacteria and endotoxins into the bloodstream, increasing the risk of urosepsis [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eNegative pressure aspiration during PCNL offers a solution to mitigate these risks by actively managing and reducing the pressure in the renal pelvis. Negative pressure aspiration helps to continuously evacuate irrigation fluid, stone fragments, and debris, thereby preventing the build-up of high pressure within the renal pelvis. By lowering renal pelvic pressure, the risk of bacterial translocation and subsequent urosepsis is significantly reduced. This is particularly important in patients with infectious stones or a history of urinary tract infections. Continuous aspiration also ensures that stone fragments and infectious material are promptly removed from the kidney, reducing the chance of postoperative infection [\u003cspan additionalcitationids=\"CR10\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTypically, the negative pressure suction function is provided by standard-channel PCNL; however, miniaturized-channel PCNL may reduce the risk of kidney injury and bleeding. Mini Percutaneous Nephrolithotomy (mini-PCNL) is a minimally invasive variation of the standard PCNL procedure that utilizes smaller instruments and access tracts. When combined with negative pressure aspiration, mini-PCNL can offer additional benefits in terms of safety and efficacy, particularly for managing infectious upper urinary tract stones [\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003eA total of 126 patients with infectious renal stones were enrolled in this retrospective study, conducted from October 2017 to May 2024. Of these patients, 57 underwent conventional mini-PCNL, while the remaining 69 underwent mini-PCNL with negative pressure aspiration. Before surgery, all patients were evaluated through routine blood and urine tests, renal function tests, coagulation profile tests, and urine cultures. For those with positive urine cultures, appropriate antibiotics were administered. Imaging examinations, including ultrasound, CT scans, or IVP, were also performed on all patients.\u003c/p\u003e\n\u003cp\u003eDemographic data and perioperative parameters, such as operation time, blood loss, hospital stay, and stone clearance rate (SCR), were recorded. Blood loss was assessed by the change in hemoglobin levels between 2 hours preoperatively and 2 hours postoperatively. The levels of serum Interleukin-6 (IL-6) and procalcitonin (PCT) were measured to evaluate the inflammatory response. Postoperative complications were assessed using the modified Clavien grading system.\u003c/p\u003e\n\u003cp\u003eA ureteral catheter was inserted through the urethra into the bladder and advanced into the renal pelvis. The patient was then placed in the prone position, and a thin needle was passed through the skin directly into the targeted renal calyx under ultrasound guidance. A guidewire was inserted through the needle into the kidney, establishing a pathway for subsequent dilation. After sequential dilation using fascial dilators, a 16 F nephrostomy sheath was inserted over the guidewire, creating a stable access route to the kidney. For patients undergoing mini-PCNL with the negative pressure aspiration technique, a specially designed nephrostomy sheath (Weili, China) was used, which connected to a suction apparatus. Continuous suction was applied throughout the procedure to evacuate stone fragments, irrigation fluid, and any blood from the kidney (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eThe nephoscope was inserted into the renal pelvis or calyx, and a holmium laser was used to break the stones into smaller fragments (Moses, Lumenis, Israel). Larger stone fragments were extracted using graspers or baskets, which were passed through the nephrostomy sheath. The negative pressure aspiration system continuously removed smaller fragments along with the irrigation fluid. Before the conclusion of the operation, a double-J stent and nephrostomy tube were placed to allow for continued drainage of urine and any remaining debris after surgery. KUB (kidney, ureter, and bladder) films combined with ultrasound were used to assess stone clearance. The nephrostomy tube was removed 1 to 4 days postoperatively, once the stones were cleared and there were no signs of infection or obstruction. The final stone clearance rate was evaluated at 3 months postoperatively.\u003c/p\u003e\n\u003cp\u003eThroughout the study, statistical analysis was done using commercially available software, including the Chi-square test, two-sample independent t test, Mann-Whitney U, and Fisher\u0026rsquo;s exact test (SPSS 30. 0 version). P\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThere were no significant differences in the age, gender, BMI or baseline health conditions between mini-PCNL with or without negative pressure aspiration. The stone baseline characteristics regarding the size, intensity and status of kidney stones were similar in both groups (Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographic data and status of stones\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGroup\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN-PCNL (N\u0026thinsp;=\u0026thinsp;69)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC- PCNL (N\u0026thinsp;=\u0026thinsp;57)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e47.51\u0026thinsp;\u0026plusmn;\u0026thinsp;11.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e46.89\u0026thinsp;\u0026plusmn;\u0026thinsp;13.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.668▼\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex ratio\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMale (41/69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMale (30/57)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.559#\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI (kg/m2) Mean (Range)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28.15(23\u0026ndash;38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.48(21\u0026ndash;35)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.13▼\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eStone status\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStone size (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.34\u0026thinsp;\u0026plusmn;\u0026thinsp;1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.22\u0026thinsp;\u0026plusmn;\u0026thinsp;0.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.519▼\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStone intensity (CT value HU)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e840.59\u0026thinsp;\u0026plusmn;\u0026thinsp;126.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e837.05\u0026thinsp;\u0026plusmn;\u0026thinsp;154.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.887▼\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStones in pelvis and calyceal (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;27(39%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;25(44%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.641#\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStaghorn stone (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;14(20%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;9(16%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eStone composition\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStruvite stones (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;19 (28%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;11(19%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.463#\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarbonate apatite stones (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;46(67%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;44(77%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAmmonium acid urate stones (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;2 (3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;1 (2%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eN-PCNL: Percutaneous nephrolithotomy (PCNL) with Negative pressure aspiration; C-PCNL: Conventional percutaneous nephrolithotomy (PCNL)\u003c/p\u003e \u003cp\u003e▼P\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistical significant between the two groups by using Independent Samples t-test (SPSS 30). #P\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistical significant between the two groups by using two side chi-square test. (SPSS 30)\u003c/p\u003e \u003cp\u003eOur data indicated that negative pressure aspiration during PCNL offered several advantages that enhanced the procedure\u0026rsquo;s safety, efficacy, and overall outcomes. The primary stone clearance rate (SCR) was significantly higher (79.7% vs. 59.6%) with the use of negative pressure suction during PCNL. Residual stones were treated with flexible ureteroscopy lithotripsy, ESWL, or a second PCNL. The final SCR remained higher with negative pressure aspiration (88.4% vs. 78.9%), although the difference was not statistically significant.\u003c/p\u003e \u003cp\u003eNegative pressure aspiration markedly decreased the incidence of postoperative fever, defined as a body temperature higher than 38.5\u0026deg;C after surgery. The incidence of postoperative fever was 8.7% in the PCNL group with negative pressure aspiration, compared to 31.6% in the conventional PCNL group. Both procalcitonin (PCT) and interleukin-6 (IL-6) levels were significantly elevated after surgery, but the negative pressure suction technique notably inhibited the rise in these infection markers. Sixteen patients required escalation of antibiotic treatment due to severe postoperative infection, while only four patients needed adjustments to their initial antibiotic therapy when the negative pressure suction technique was used.\u003c/p\u003e \u003cp\u003eUrosepsis, a severe and potentially life-threatening condition where a urinary tract infection spreads into the bloodstream causing systemic infection, occurred in only 2.9% of patients with negative pressure aspiration during PCNL, compared to 14% in the group without negative pressure suction. In the PCNL group without negative pressure aspiration, two patients were diagnosed with uroseptic shock and were transferred to the ICU for further treatment.\u003c/p\u003e \u003cp\u003eThe decrease in hemoglobin between pre- and postoperative measurements was used to assess blood loss during the operation. The data showed that the use of negative pressure aspiration significantly reduced blood loss. A total of four patients required blood transfusions, with only one of them having undergone surgery with negative pressure aspiration. Two patients eventually required selective renal artery embolization therapy due to severe arterial bleeding, and both had undergone surgery without negative pressure aspiration.\u003c/p\u003e \u003cp\u003eOther general postoperative complications were assessed using the Modified Clavien-Dindo Classification system. The complication scores were similar between the two groups, regardless of whether negative pressure aspiration was used. The data also showed that negative pressure aspiration during PCNL helped patients return to normal activities more quickly. The average time to return to normal activity was 2.41 days for patients in the PCNL group with negative pressure aspiration, compared to 3.05 days for those undergoing traditional PCNL. The average postoperative hospital stay was 3.44 days and 4.47 days, respectively, for patients with and without negative pressure aspiration during the operation. These differences were statistically significant (Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe comparison of operation outcome and complications between PCNL with and without negative pressure aspiration.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN-PCNL(N\u0026thinsp;=\u0026thinsp;69)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eC-PCNL(N\u0026thinsp;=\u0026thinsp;57)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOperation time (minutes)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90.00\u0026thinsp;\u0026plusmn;\u0026thinsp;29.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e84.74\u0026thinsp;\u0026plusmn;\u0026thinsp;30.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u0026thinsp;=\u0026thinsp;0.173*\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrimary stone clearance (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;55 (79.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eN\u0026thinsp;=\u0026thinsp;34 (59.6%)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u0026thinsp;=\u003c/em\u003e\u0026thinsp;0.024#\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFinal stone clearance (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;61 (88.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;45 (78.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.230#\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePostoperative hospital stay (day)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.44\u0026thinsp;\u0026plusmn;\u0026thinsp;1.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.47\u0026thinsp;\u0026plusmn;\u0026thinsp;2.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.011*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime of return to normal activity(day)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.41\u0026thinsp;\u0026plusmn;\u0026thinsp;1.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.005*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePost operative fever (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;6 (8.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;18 (31.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.003#\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum IL-6 (pg/ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e51.20\u0026thinsp;\u0026plusmn;\u0026thinsp;44.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e82.35\u0026thinsp;\u0026plusmn;\u0026thinsp;91.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.023*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum Pct (ng/ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.14\u0026thinsp;\u0026plusmn;\u0026thinsp;5.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.38\u0026thinsp;\u0026plusmn;\u0026thinsp;18.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.006*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEscalation of antibiotic therapy (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;4 (5.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;16(28.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u0026thinsp;=\u0026thinsp;0.001#\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUrosepsis (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;2 (2.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;8 (14%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u0026thinsp;=\u0026thinsp;0.048#\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ehemoglobin decrease, mg/dl\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15.12\u0026thinsp;\u0026plusmn;\u0026thinsp;8.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21.82\u0026thinsp;\u0026plusmn;\u0026thinsp;12.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP\u0026thinsp;\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eClassification of complications\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.148#\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade 0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade I\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade II\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMore than Grade II\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eN-PCNL: percutaneous nephrolithotomy(PCNL)with negative pressure aspiration. C-PCNL: Conventional percutaneous nephrolithotomy.\u003c/p\u003e \u003cp\u003e \u003cem\u003e* P\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistical significant between the two groups by using Mann-Whitney-U test (SPSS 30). #\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistical significant between the two groups by using two side chi-square test (SPSS 30).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eCompared with traditional PCNL, negative pressure aspiration during operation offers several advantages that enhance the procedure's safety, efficacy, and overall outcomes. One of the main benefits of negative pressure aspiration is its ability to maintain low intrarenal pressure [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Traditional PCNL can increase the pressure inside the kidney, potentially causing complications like fluid absorption or damage to kidney structures. Negative pressure suction helps to prevent this by constantly aspirating fluids and debris. Keeping a lower pressure of renal pelvis is very important to reduce the risk of bacteria and toxins being forced into the bloodstream, thereby lowering the incidence of urosepsis, a serious postoperative infection that can occur during PCNL. Our results confirmed that the incidence of urosepsis was significantly decreased for those patients by using negative pressure aspiration during operation.\u003c/p\u003e \u003cp\u003eStudies have shown that PCNL with negative pressure aspiration is associated with a lower incidence of postoperative fever, which is often a sign of infection [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. By minimizing fluid retention and bacterial spread during surgery, the body's inflammatory response is reduced. Our data was insistent with these literatures. Additionally, the suction technique may help lower proinflammatory markers, such as interleukin-6 (IL-6) and procalcitonin (PCT), which are elevated in response to infections. IL-6 is a key cytokine, involved in inflammation and the immune response. Infections and endotoxemia can significantly elevate IL-6 levels [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Lower IL-6 levels are associated with a reduced inflammatory response and fewer postoperative complications such as fever and systemic inflammatory response syndrome (SIRS) [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. High PCT levels postoperatively indicate a systemic inflammatory response often due to infection. And lower PCT levels postoperatively suggest a lower risk of severe infections, allowing for quicker recovery and reducing the need for aggressive antibiotic treatments [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Our data confirmed that the elevation o IL-6 and Pct during the procedure were significantly inhibited by using suction technique. We considered that negative pressure aspiration helps maintain a lower intrarenal pressure and continuously removes infected debris, blood, and irrigation fluids, reducing the overall inflammatory response during PCNL.\u003c/p\u003e \u003cp\u003eStudies shown that negative pressure aspiration during PCNL contributes to a better SCR by enhancing the removal of stone fragments during the procedure [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Our study confirmed a significant higher primary SCR by using suction technique during PCNL. Several reasons were considered to explain how it works to promote the SCR. Firstly, negative pressure aspiration is to provide continuous suction during the procedure, which helps to consistently remove stone fragments as they are being broken down. The immediate removal of fragments as they are broken by the holmium laser results in more efficient fragment evacuation, leading to a higher SCR. Secondly, consistent suction helps to prevent fragment migration during operation. In traditional PCNL, stone fragments may move around or migrate to other parts of the kidney, making them harder to remove. Negative pressure aspiration helps to keep the surgical field clear and prevents the migration of fragments, enabling the surgeon to target and remove them more easily. Thirdly, it can provide a clearer surgical field. Continuous aspiration clears blood, irrigation fluid, and debris from the surgical field, providing the surgeon with a clear view of the operative area. The enhanced visibility allows for more precise targeting and fragmentation of the stones during the procedure. Lastly, negative pressure aspiration helps to provide longer operating time for more complete clearance. Since negative pressure suction maintains low intrarenal pressure, it allows for a longer and safer operating time. Surgeons can take their time ensuring all stone fragments are removed without worrying about complications from high pressure, leading to more complete stone clearance.\u003c/p\u003e \u003cp\u003eNegative pressure aspiration was also demonstrated to result in less blood loss compared to traditional PCNL in our study. It provides continuous suction that actively removes blood from the surgical field. Thus, the surgeon can better visualize the surgical area, leading to more precise and controlled maneuvers. This reduces inadvertent trauma to blood vessels, minimizing blood loss. Additionally, maintaining a clear surgical field allows for better identification and management of bleeding sources. Surgeons can promptly address bleeding vessels with cauterization or other hemostatic techniques, reducing overall blood loss. Another impossible reason of negative pressure aspiration can reduce bleeding is to control renal pressure during the operation. Traditional PCNL can lead to increased intrarenal pressure, which may cause more bleeding from damaged blood vessels [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. However, negative pressure aspiration helps maintain low intrarenal pressure, reducing the likelihood of ruptured blood vessels or excessive bleeding from the kidney tissues [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Lower intrarenal pressure also minimizes the risk of blood and fluid leaking into surrounding tissues, further controlling blood loss.\u003c/p\u003e \u003cp\u003eOur data showed a shorter hospital stay and quicker return to normal activities by using negative pressure aspiration compare to traditional PCNL. Negative pressure aspiration minimizes the risk of complications like infection, bleeding, and urosepsis by maintaining low intrarenal pressure and effectively removing stone fragments and bacteria. Fewer complications mean patients experience less postoperative distress, leading to a smoother and quicker recovery.\u003c/p\u003e \u003cp\u003eFurthermore, maintaining low intrarenal pressure reduces the risk of bacterial and toxin translocation into the bloodstream, lowering the incidence of postoperative infections. Fewer infections lead to fewer complications, shorter hospital stays, and a more straightforward recovery process. As negative pressure aspiration helps reduce blood loss during the procedure, patients experience less anemia and quicker physiological recovery after surgery. This enables them to regain strength and return to normal activities sooner.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn this study, the priority of negative pressure aspiration during PCNL is highlighted as a significant advancement in the treatment of infectious kidney stones. The study demonstrates that incorporating negative pressure aspiration into PCNL improves surgical outcomes in several key areas. (1) Negative pressure aspiration leads to more effective removal of stone fragments. (2) The technique helps maintain low intrarenal pressure, significantly reducing the risk of infection, particularly urosepsis, and lowering postoperative fever rates. (3) Continuous suction allows for better control of bleeding, resulting in less intraoperative blood loss and improved surgical field visibility. (4) Due to fewer complications and less trauma during the procedure, patients experience faster recovery times, reduced inflammation, and quicker discharge from the hospital. Our study concludes that negative pressure aspiration should be considered a priority technique in PCNL, as it enhances stone clearance, minimizes complications, reduces blood loss, and improves overall patient recovery. Its integration into PCNL makes it a superior method for managing infectious kidney stones compared to conventional techniques.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eXiang Li designed the study and drafted the main workWei Chen did participate in research work and contribute to writing portions of the content. Xingfa Chen supervise the studyQinzhi Long acquisition and analysisHui He participate in reviewing and revising the research paper Na Zhang prepared the literature review\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eRodman JS. Struvite stones. \u003cem\u003eNephron\u003c/em\u003e. 1999;81 Suppl 1:50-9.\u003c/li\u003e\n\u003cli\u003eMiano R, Germani S, Vespasiani G. Stones and urinary tract infections. \u003cem\u003eUrol Int\u003c/em\u003e. 2007;79 Suppl 1:32-6.\u003c/li\u003e\n\u003cli\u003ePichette V, Bonnardeaux A, Cardinal J, Houde M, Nolin L, Boucher A, Ouimet D. Ammonium acid urate crystal formation in adult North American stone-formers. \u003cem\u003eAm J Kidney Dis\u003c/em\u003e. 1997;30(2):237-42.\u003c/li\u003e\n\u003cli\u003eMarien T, Miller NL. Treatment of the infected stone. \u003cem\u003eUrol Clin North Am\u003c/em\u003e. 2015;42(4):459-72.\u003c/li\u003e\n\u003cli\u003eKhusid JA, Hordines JC, Sadiq AS, Atallah WM, Gupta M. Prevention and management of infectious complications of retrograde intrarenal surgery. \u003cem\u003eFront Surg\u003c/em\u003e. 2021;8:718583.\u003c/li\u003e\n\u003cli\u003eYuan W, Li Y, Dai Y, Luo C, Zhang H, Xiong H. Efficacy of super-mini-PCNL and ureteroscopy in kidney stone sufferers and risk factors of postoperative infection. \u003cem\u003eJ Healthc Eng\u003c/em\u003e. 2022;2022:4733329.\u003c/li\u003e\n\u003cli\u003eKyriazis I, Panagopoulos V, Kallidonis P, \u0026Ouml;zsoy M, Vasilas M, Liatsikos E. Complications in percutaneous nephrolithotomy. \u003cem\u003eWorld J Urol\u003c/em\u003e. 2015;33(8):1069-77.\u003c/li\u003e\n\u003cli\u003eZhou G, Zhou Y, Chen R, Wang D, Zhou S, Zhong J, Zhao Y, Wan C, Yang B, Xu J, et al. The influencing factors of infectious complications after percutaneous nephrolithotomy: a systematic review and meta-analysis. \u003cem\u003eUrolithiasis\u003c/em\u003e. 2022;51(1):17.\u003c/li\u003e\n\u003cli\u003eTzelves L, Skolarikos A. Suction use during endourological procedures. \u003cem\u003eCurr Urol Rep\u003c/em\u003e. 2020;21(11):46.\u003c/li\u003e\n\u003cli\u003eZeng G, Zhao Z, Liu Y. Ultrasound-guided mini percutaneous nephrolithotomy with suction sheath. \u003cem\u003eJ Endourol\u003c/em\u003e. 2022;36(S2).\u003c/li\u003e\n\u003cli\u003eNizzardo M, Albo G, Ripa F, Zino E, De Lorenzis E, Boeri L, Longo F, Montanari E, Zanetti SP. Assessment of effectiveness and safety of aspiration-assisted nephrostomic access sheaths in PCNL and intrarenal pressures evaluation: a systematic review of the literature. \u003cem\u003eJ Clin Med\u003c/em\u003e. 2024;13(9):2558.\u003c/li\u003e\n\u003cli\u003ePatil A, Sharma R, Shah D, Gupta A, Singh A, Ganpule A, Sabnis R, Desai M. A prospective comparative study of mini-PCNL using Trilogy\u0026trade; or thulium fibre laser with suction. \u003cem\u003eWorld J Urol\u003c/em\u003e. 2022;40(2):539-43.\u003c/li\u003e\n\u003cli\u003eKankaria S, Gali KV, Chawla A, Bhaskara SP, Hegde P, Somani B, de la Rosette J, Laguna P. Super-mini PCNL (SMP) with suction versus standard PCNL for the management of renal calculi of 1.5 cm-3 cm: a randomized controlled study from a university teaching hospital. \u003cem\u003eWorld J Urol\u003c/em\u003e. 2024;42(1):257.\u003c/li\u003e\n\u003cli\u003eZanetti SP, Lievore E, Fontana M, Turetti M, Gallioli A, Longo F, Albo G, De Lorenzis E, Montanari E. Vacuum-assisted mini-percutaneous nephrolithotomy: a new perspective in fragments clearance and intrarenal pressure control. \u003cem\u003eWorld J Urol\u003c/em\u003e. 2021;39(6):1717-23.\u003c/li\u003e\n\u003cli\u003eDe Stefano V, Castellani D, Somani BK, Giulioni C, Cormio A, Galosi AB, Sarica K, Glover X, da Silva RD, Tanidir Y, et al. 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Retrograde intrarenal surgery for lithiasis using suctioning devices: a shift in paradigm? \u003cem\u003eJ Clin Med\u003c/em\u003e. 2024;13(9):2493.\u003c/li\u003e\n\u003c/ol\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":"Negative pressure aspiration, PCNL, kidney stones, infection","lastPublishedDoi":"10.21203/rs.3.rs-5422838/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5422838/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003ePercutaneous nephrolithotomy (PCNL) is the preferred treatment for large and complex infectious kidney stones but is associated with a risk of urosepsis due to elevated renal pelvic pressure. Negative pressure aspiration during PCNL may mitigate this risk by continuously evacuating irrigation fluid, stone fragments, and bacteria, thereby lowering intrarenal pressure and reducing postoperative complications. This study evaluates the safety and efficacy of PCNL with negative pressure aspiration for treating infectious kidney stones.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA retrospective study included 126 patients with infectious renal stones treated from October 2017 to May 2024. Among them, 57 underwent conventional mini-PCNL, and 69 received mini-PCNL with negative pressure aspiration. Demographic data and perioperative parameters, including operation time, blood loss, hospital stay, and stone clearance rate (SCR), were recorded. Blood loss was assessed by hemoglobin changes, and inflammatory responses were measured using serum IL-6 and procalcitonin (PCT) levels. Postoperative complications were classified using the Modified Clavien-Dindo Classification system.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eNegative pressure aspiration significantly improved primary SCR (79.7% vs. 59.6%) and reduced postoperative fever incidence (8.7% vs. 31.6%) compared to conventional PCNL. The incidence of urosepsis was lower (2.9% vs. 14%), and blood loss was reduced, with fewer transfusions required. Patients treated with negative pressure aspiration recovered faster, resuming normal activities in an average of 2.41\u0026thinsp;\u0026plusmn;\u0026thinsp;1.35 days compared to 3.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.78 days for conventional PCNL patients. The average hospital stay was shorter for patients with negative pressure aspiration (3.44 vs. 4.47 days).\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eNegative pressure aspiration during PCNL offers significant benefits, including improved stone clearance, reduced postoperative complications, lower infection risk, and faster recovery. This technique should be considered a preferred option for treating infectious kidney stones, demonstrating superior surgical outcomes and enhanced patient recovery compared to traditional PCNL.\u003c/p\u003e","manuscriptTitle":"Efficacy and Safety of Negative Pressure Aspiration in Percutaneous Nephrolithotomy for Infectious Kidney Stones: A Retrospective Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-16 16:56:18","doi":"10.21203/rs.3.rs-5422838/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":"ac2e5b8c-003f-4670-a449-d039bafa30fb","owner":[],"postedDate":"December 16th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-05-08T16:23:34+00:00","versionOfRecord":[],"versionCreatedAt":"2024-12-16 16:56:18","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5422838","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5422838","identity":"rs-5422838","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}