Comparison of Ultrasound-Guided Erector Spinae Plane and Transversus Abdominis Plane Blocks for Postoperative Analgesia in Laparoscopic Bariatric Surgery

Comparison of Ultrasound-Guided Erector Spinae Plane and Transversus Abdominis Plane Blocks for Postoperative Analgesia in Laparoscopic Bariatric Surgery | 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 Comparison of Ultrasound-Guided Erector Spinae Plane and Transversus Abdominis Plane Blocks for Postoperative Analgesia in Laparoscopic Bariatric Surgery Ergun GUNDUZ, Mehmet SARI This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8804510/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 pain management in bariatric surgery remains challenging, particularly in patients with obesity-related comorbidities that limit opioid use. Ultrasound-guided regional anesthesia techniques are therefore essential components of multimodal analgesia. Among these, the transversus abdominis plane (TAP) block and the erector spinae plane (ESP) block are commonly used, yet comparative data in bariatric surgery are limited. Methods: This retrospective observational study included adult patients who underwent elective laparoscopic sleeve gastrectomy and received either an ultrasound-guided TAP block or ESP block as part of postoperative analgesia. All patients received standardized general anesthesia and multimodal analgesia. Postoperative pain was assessed using the Visual Analog Scale and analyzed as categorical pain distributions at predefined time points. Perioperative hemodynamic parameters, time to first rescue analgesia, and postoperative adverse events were also evaluated. Results: A total of 64 patients were analyzed (TAP group, n = 30; ESP group, n = 34). Demographic characteristics, intraoperative variables, and perioperative hemodynamic parameters were comparable between groups. The proportion of pain-free patients was significantly higher in the ESP group at postoperative 2 hours, whereas pain distribution at later time points (6–48 hours) was similar between groups. Time to first rescue analgesia and the incidence of postoperative adverse events did not differ significantly. Conclusions: Both TAP and ESP blocks provided effective and safe postoperative analgesia following laparoscopic bariatric surgery. The ESP block was associated with superior early postoperative pain control, while overall analgesic efficacy and safety profiles were comparable between techniques. ESP block may be preferentially considered when enhanced early postoperative analgesia is desired. Surgery Anesthesiology & Pain Medicine Bariatric surgery Erector spinae plane block Transversus abdominis plane block Postoperative pain Regional anesthesia Introduction Obesity is a growing global health problem worldwide and is associated with increased morbidity and mortality (1). Bariatric surgery remains the most effective long-term treatment for patients with severe obesity, providing sustained weight loss and improvement in obesity-related comorbidities (2). Despite advances in surgical techniques, postoperative pain management in bariatric patients remains challenging and may adversely affect early mobilization, respiratory function, and recovery (3). Effective postoperative analgesia is particularly important in this population because obesity-related comorbidities, such as obstructive sleep apnea, limit opioid use and increase the risk of opioid-related adverse events (4). Consequently, ultrasound-guided regional anesthesia techniques have become integral components of multimodal analgesia strategies in bariatric surgery (5,6). Among these techniques, the transversus abdominis plane (TAP) block and the erector spinae plane (ESP) block are commonly used for postoperative pain control after laparoscopic abdominal surgery (7,8). The TAP block primarily provides somatic analgesia of the anterior abdominal wall but may offer limited visceral analgesia and inconsistent coverage of upper thoracic dermatomes in obese patients (9,10). In contrast, the ESP block is thought to allow wider cranio-caudal spread of local anesthetic, potentially providing both somatic and visceral analgesia (11,12). However, comparative data regarding the relative analgesic efficacy of ESP and TAP blocks in obese patients undergoing laparoscopic bariatric surgery remain limited and sometimes conflicting (6,13). Therefore, this study aimed to compare the postoperative analgesic efficacy and safety of ultrasound-guided ESP and TAP blocks in patients undergoing laparoscopic sleeve gastrectomy. Methods This retrospective observational study was conducted in accordance with the Declaration of Helsinki after approval by the Institutional Research Ethics Committee. Medical records of adult patients who underwent elective laparoscopic sleeve gastrectomy were retrospectively reviewed. Patients were included if they received either an ultrasound-guided transversus abdominis plane (TAP) block or erector spinae plane (ESP) block as part of postoperative analgesia. Patients with incomplete records, conversion to open surgery, or missing postoperative pain assessments were excluded. In our clinic, all patients are given standard general anesthesia with propofol (2.5 mg/kg), fentanyl (2 µg/kg), and rocuronium (0.6 mg/kg) for induction, followed by maintenance anesthesia with sevoflurane (2%) in a 50% oxygen-air mixture. Standard intraoperative monitoring, electrocardiography, non-invasive blood pressure, pulse oximetry, and end-respiratory carbon dioxide monitoring are recorded on the follow-up form. All patients receive standard multimodal analgesia consisting of intravenous paracetamol and nonsteroidal anti-inflammatory drugs, with opioids only used as rescue analgesia. Patients were grouped according to the regional anesthesia technique documented in their medical records. Ultrasound-guided TAP block is applied bilaterally at the end of surgery under aseptic conditions, using a linear ultrasound probe placed in the mid-axillary line between the iliac crest and the costal margin. Local anesthesia is injected into the fascial plane between the internal oblique and transversus abdominis muscles using hydrodissection guided by real-time ultrasound. Ultrasound-guided ESP block is applied bilaterally at the thoracic level. Local anesthesia is injected into the fascial plane deep to the erector spinae muscle at the level of the transverse process. Both blocks are applied using the same local anesthetic mixture, and the total doses do not exceed the recommended safety limits (2 mg/kg). Outcomes The primary outcome was postoperative pain intensity assessed using the Visual Analog Scale (VAS) at predefined time points during the first 24 hours postoperatively. Secondary outcomes included:Distribution of postoperative pain categories, Time to first rescue analgesia, Perioperative hemodynamic parameters, Incidence of postoperative adverse events like bradycardia, hypotension, nausea, vomiting. Given the retrospective design, non-normal distribution of pain scores, and limited sample size, postoperative pain was analyzed using categorical pain distributions rather than continuous VAS values. Statistical Analysis Continuous variables were presented as mean ± standard deviation or median (min–max), and categorical variables as number and percentage. Between-group comparisons were performed using the Mann–Whitney U test for continuous variables and the chi-square or Fisher’s exact test for categorical variables, as appropriate. A p value < 0.05 was considered statistically significant. Results A total of 64 patients were included in the final analysis, with 30 patients in the TAP block group and 34 patients in the ESP block group. Demographic characteristics, including age, body weight, height, body mass index, and ASA physical status, were comparable between groups, with no statistically significant differences observed (all p > 0.05). Intraoperative and Hemodynamic Data Duration of anesthesia, intraoperative fluid administration, and estimated blood loss were similar between the TAP and ESP groups. Mean arterial pressure, heart rate, and oxygen saturation remained stable throughout the perioperative period and did not differ significantly between groups at any measured time point. Postoperative Pain Outcomes In the post-anesthesia care unit, a higher proportion of patients in the ESP group were pain-free compared with the TAP group; however, this difference did not reach statistical significance. At postoperative 2 hours, the proportion of pain-free patients was significantly higher in the ESP group than in the TAP group (p < 0.05). At postoperative 6, 12, 24, and 48 hours, pain distribution was comparable between groups, with no statistically significant differences observed. Rescue Analgesia and Adverse Events Time to first rescue analgesia did not differ significantly between the TAP and ESP groups. Postoperative adverse events, including bradycardia, hypotension, and postoperative nausea and vomiting, were infrequent and comparable between groups. No cases of local anesthetic systemic toxicity or block-related complications were observed. Discussion Although continuous VAS scores are frequently used in postoperative pain studies, in this study pain was analyzed using categorical pain distributions. This approach was chosen to highlight the percentage of pain-free patients, especially in the early postoperative period; this percentage is a significant predictor of patient comfort, mobilization, and satisfaction. Furthermore, categorical analysis is less sensitive to inter-individual variability in pain perception and reporting, which may be more pronounced in obese patients. Given the retrospective design, the non-normal distribution of pain scores, and the relatively small sample size, categorical pain analysis using the chi-square test was considered a more robust and clinically interpretable method. Similar categorical approaches to postoperative pain assessment have been previously used to enhance clinical interpretability in regional anesthesia studies. (16, 17). The principal finding of this study is that the ultrasound-guided erector spinae plane (ESP) block provided superior early postoperative analgesia compared with the transversus abdominis plane (TAP) block in patients undergoing laparoscopic sleeve gastrectomy. This difference was most pronounced during the early postoperative period, particularly at the second postoperative hour, while pain scores at later time points were comparable between the two techniques. These findings support the role of ESP block as an effective component of multimodal analgesia in bariatric surgery. The early analgesic advantage observed with ESP block may be explained by its proposed mechanism of action. Anatomical, cadaveric, and imaging studies suggest that local anesthetic injected into the erector spinae plane can spread cranio-caudally and anteriorly toward the paravertebral and epidural spaces, potentially resulting in blockade of both dorsal and ventral rami as well as sympathetic fibers (11, 12, 18). This broader spread may allow ESP block to provide partial visceral analgesia in addition to somatic analgesia, which is particularly relevant in laparoscopic bariatric surgery where visceral pain contributes significantly to postoperative discomfort. In contrast, the TAP block primarily targets the somatic nerves of the anterior abdominal wall and has limited effect on visceral pain pathways (9, 19). Moreover, in obese patients, increased subcutaneous adipose tissue and altered anatomy may compromise ultrasound visualization and the reliability of local anesthetic spread within the transversus abdominis plane (7, 20). These factors may partially explain the less pronounced early analgesic effect observed with TAP block in the present study. Our findings are consistent with previously published randomized controlled trials comparing ESP and TAP blocks in bariatric and laparoscopic abdominal surgery. Mu et al. demonstrated that ESP block at the T9 level provided superior early postoperative analgesia and improved recovery profiles compared with TAP block in patients undergoing laparoscopic sleeve gastrectomy (6). Similarly, Elshazly et al. reported significantly lower early postoperative pain scores with ESP block following laparoscopic bariatric surgery (13). In addition, recent systematic reviews and meta-analyses have suggested that ESP block may offer improved early analgesic efficacy compared with TAP block, although heterogeneity among studies remains substantial (8,21,22). Despite the early analgesic superiority of ESP block, pain scores beyond the immediate postoperative period were comparable between groups. This finding suggests that both ESP and TAP blocks are effective regional anesthesia techniques when incorporated into a standardized multimodal analgesia regimen. From a clinical perspective, this supports the individualized selection of regional anesthesia techniques based on patient anatomy, surgical characteristics, and practitioner expertise rather than a one-size-fits-all approach (23, 24). Importantly, both techniques demonstrated favorable safety profiles in this high-risk obese population. No cases of local anesthetic systemic toxicity or block-related complications were observed, and perioperative hemodynamic parameters remained stable in both groups. These findings are consistent with previous studies emphasizing the safety of ultrasound-guided fascial plane blocks in bariatric surgery and other high-risk surgical populations (5,7,25). From a practical standpoint, ESP block may offer technical advantages in obese patients due to more reliable ultrasound landmarks, such as the transverse process, compared with the deeper and less distinct fascial planes targeted in TAP block. Although block performance time and technical difficulty were not formally assessed in this study, this observation has been increasingly reported in the literature and may have implications for clinical workflow and block success rates in patients with high body mass index (19,26,27,28). The present study demonstrates that both TAP and ESP blocks provide hemodynamically stable and safe perioperative analgesia in patients undergoing bariatric surgery. The absence of significant differences in cardiovascular and respiratory parameters across all perioperative phases indicates that both regional techniques are well tolerated in this high-risk patient population. From an analgesic perspective, the ESP block showed a distinct advantage in the early postoperative period, particularly at 2 hours after surgery, where a significantly higher proportion of patients were pain-free. This early benefit may be related to the broader dermatomal spread and potential paravertebral or central modulation associated with the ESP block. However, beyond the early postoperative phase, pain control was comparable between groups, suggesting that both techniques provide similar mid- and late-term analgesic efficacy. The low and comparable incidence of adverse events further supports the clinical safety of both blocks. Overall, these findings indicate that while the ESP block may offer superior early postoperative pain control, TAP and ESP blocks have comparable overall effectiveness and safety profiles throughout the postoperative course. Conclusion In patients undergoing laparoscopic bariatric surgery, both ultrasound-guided transversus abdominis plane and erector spinae plane blocks provided effective and safe postoperative analgesia as part of a multimodal analgesic regimen, with preserved perioperative hemodynamic stability and a low incidence of adverse events. The erector spinae plane block was associated with superior early postoperative pain control, particularly within the first postoperative hours, whereas analgesic efficacy in the mid- and late postoperative periods was comparable between techniques. These findings suggest that while both blocks represent reliable regional anesthesia options in bariatric surgery, the erector spinae plane block may be preferentially considered when enhanced early postoperative analgesia is desired, without compromising overall safety. References Blair SN, Nichaman MZ. The public health problem of increasing prevalence rates of obesity and what should be done about it. Mayo Clin Proc. 2002 Feb;77(2):109-13. doi: 10.4065/77.2.109. Nedelcut S, Axer S, Olbers T. The risk and benefit of revisional vs. primary metabolic- bariatric surgery and drug therapy - A narrative review. Metabolism. 2024 May;154:155799. doi: 10.1016/j.metabol.2024.155799. Baytar Ç, Gürbüz Z, Köksal İncegül BG, Baytar MS, Taşdöven İ, Pişkin Ö. Effects of modified thoracoabdominal nerves block through pericondrial approach on postoperative pulmonary functions in laparoscopic bariatric surgery: a randomized controlled study. Obes Surg 2025 May 21. doi:10.1007/s11695-025-07908-3. 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Eur Spine J. 2024;33(3):949-955. doi:10.1007/s00586-023-07881-4 Qian L, Hu N-q, Shen Q-h and Ni K (2025) Comparison of the efficiency of ultrasound-guided ESPB and TAPB on postoperative analgesia: a system review and meta-analysis. Front. Med. 12:1595778. doi: 10.3389/fmed.2025.1595778 Mansour MA, Baradwan S, Shama AA, et al. Erector spinae plane block versus transversus abdominis plane block for analgesia after cesarean section: a systematic review and meta-analysis. Braz J Anesthesiol. 2025;75(4):844606. doi:10.1016/j.bjane. 2025.844606 Tables Table 1 Demographic characteristics, anesthesia-related parameters, intraoperative findings, and early postoperative outcomes of the study population (n = 64). Variable Min–Max Median Mean ± SD / n (%) Age (years) 19.0 – 67.0 32.5 35.2 ± 11.9 Weight (kg) 81.0 – 184.0 110.5 118.4 ± 23.0 Height (cm) 142.0 – 191.0 165.0 166.2 ± 10.6 Body Mass Index (kg/m²) 32.5 – 52.3 41.4 43.0 ± 8.6 Regional Block Type TAP block – – 30 (46.9%) ESP block – – 34 (53.1%) Duration of Anesthesia (min) 60.0 – 180.0 80.0 86.4 ± 21.1 Intraoperative Fluid (mL) 400.0 – 1500.0 700.0 738.3 ± 182.5 Intraoperative Blood Loss (mL) 0.0 – 150.0 50.0 51.7 ± 20.6 Mean Arterial Pressure (mmHg) 64.0 – 115.0 90.5 92.5 ± 11.7 Heart Rate (beats/min) 60.0 – 100.0 79.0 80.2 ± 11.3 SpO₂ (%) 72.0 – 100.0 98.0 97.5 ± 4.2 Time to First Rescue Analgesia (min) 0.0 – 900.0 0.0 47.6 ± 166.3 PACU Adverse Events Bradycardia – – 2 (3.1%) Hypotension – – 4 (6.3%) Vomiting – – 7 (10.9%) m Mann-whitney u test / X² Ki-kare test (Fischer test) Table 2. Perioperative Hemodynamic Parameters and Postoperative Adverse Events Variable TAP (n=30) Mean ± SD / n (%) ESP (n=34) Mean ± SD / n (%) p value Mean Arterial Pressure (mmHg) Preoperative 94.6 ± 10.3 90.6 ± 12.7 0.206 Intraoperative 95.0 ± 13.6 95.1 ± 22.2 0.261 PACU 94.3 ± 9.1 92.2 ± 11.5 0.312 Postoperative 24 h 94.6 ± 10.2 91.5 ± 11.5 0.178 Heart Rate (beats/min) Preoperative 81.9 ± 11.4 78.6 ± 11.2 0.166 PACU 80.6 ± 16.0 78.2 ± 14.8 0.653 Postoperative 24 h 83.2 ± 9.9 80.9 ± 10.4 0.309 SpO₂ (%) Preoperative 97.3 ± 5.9 97.7 ± 1.6 0.081 PACU 97.2 ± 2.5 97.6 ± 1.3 0.950 Time to First Rescue Analgesia (min) 100.3 ± 233.7 100.1 ± 230.0 0.782 Postoperative Adverse Events Bradycardia 1 (3.3%) 1 (2.9%) 1.000 Hypotension 2 (6.7%) 2 (5.9%) 1.000 Vomiting (PACU) 5 (16.7%) 2 (5.9%) 0.168 Vomiting (2 h) 6 (20.0%) 2 (5.9%) 0.088 Vomiting (≥6 h) 0 0 – Table 3. Postoperative Pain Distribution According to Groups Pain category TAP (n=30) n (%) ESP (n=34) n (%) p value PACU No pain 5 (16.7) 13 (38.2) 0.055 Very mild 15 (50.0) 15 (44.1) Mild 8 (26.7) 5 (14.7) Moderate 2 (6.7) 1 (2.9) Severe 0 0 (0.0) No pain 0 0 (0.0) Postoperative 2 Hours No pain 7 (23.3) 17 (50.0) 0.028 Very mild 16 (53.3) 7 (20.6) Mild 6 (20.0) 7 (20.6) Moderate 1 (3.3) 2 (5.9) Severe 0 (0.0) 1 (2.9) Postoperative 6 Hours No pain 10 (33.3) 18 (52.9) 0.115 Very mild 15 (50.0) 12 (35.3) Mild 3 (10.0) 3 (8.8) Moderate 2 (6.7) 0 (0.0) Severe 0 (0.0) 1 (2.9) Postoperative 12 Hours No pain 18 (60.0) 18 (52.9) 0.570 Very mild 10 (33.3) 13 (38.2) Mild 2 (6.7) 3 (8.8) Moderate 0 0 (0.0) Severe 0 0 (0.0) Postoperative 24 Hours No pain 20 (66.7) 19 (55.9) 0.378 Very mild 10 (33.3) 14 (41.2) Mild 0 (0.0) 1 (2.9) Moderate 0 (0.0) 0 (0.0) Severe 0 (0.0) 0 (0.0) Postoperative 48 Hours No pain 21 (70.0) 18 (52.9) 0.163 Very mild 8 (26.7) 16 (47.1) Mild 1 (3.3) 0 (0.0) Moderate 0 (0.0) 0 (0.0) Severe 0 (0.0) 0 (0.0) Chi-square (χ²) test was used for between-group comparisons Statistically significant p values are shown in bold Additional Declarations The authors declare no competing interests. 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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-8804510","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":586840098,"identity":"f61a8947-ebd8-4bf0-bea4-ff86837e3e27","order_by":0,"name":"Ergun GUNDUZ","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABB0lEQVRIiWNgGAWjYHCDBAaGDwwMMmA2D7FaGGcwGPDAtEgQpYWZhxgt/NLHr0kXMNQmbmfPMf5sU/OHh7//AOODt20MdeYN2LVI9uWUSc9gOJ64s+eNgXHOMQMeiRsJzIZz2xgkZA5g12JwhidNmofhWOKGGzkGyTlsQIfdYGCT5gVqweUye2Qthy3+GfDInz/A/hufFgMe9mNALTUgLYbNjG0GPAYHEtiY8WmROMPDbA1UZrzhzLNixt4+Yx7DG4nNknPOSUjOwBViPewPb/NU1MluOJ68+cOPb3JycucPH/zwpsyGH3fE8BgAnXcYWYSxgQF/TLI/ABJ1eBSMglEwCkbBiAcAgPJQ3nqAAioAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-5344-8250","institution":"Istanbul Atlas University, School of Medicine,Dept. of Anesthesiology","correspondingAuthor":true,"prefix":"","firstName":"Ergun","middleName":"","lastName":"GUNDUZ","suffix":""},{"id":586840099,"identity":"73daa5b6-22e9-49a5-a2ab-11c793005f47","order_by":1,"name":"Mehmet SARI","email":"","orcid":"https://orcid.org/0000-0002-7114-2239","institution":"Bezmialem Vakif University","correspondingAuthor":false,"prefix":"","firstName":"Mehmet","middleName":"","lastName":"SARI","suffix":""}],"badges":[],"createdAt":"2026-02-06 08:32:12","currentVersionCode":1,"declarations":{"humanSubjects":true,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":true,"humanSubjectConsent":true,"humanSubjectClinicalTrial":true,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-8804510/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8804510/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102296829,"identity":"d6176279-f4dd-4371-b2a4-72e0e3429d50","added_by":"auto","created_at":"2026-02-10 10:22:03","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":818001,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8804510/v1/6504da29-758c-4db2-ad35-0f50bb8d6915.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eComparison of Ultrasound-Guided Erector Spinae Plane and Transversus Abdominis Plane Blocks for Postoperative Analgesia in Laparoscopic Bariatric Surgery\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eObesity is a growing global health problem worldwide and is associated with increased morbidity and mortality (1). Bariatric surgery remains the most effective long-term treatment for patients with severe obesity, providing sustained weight loss and improvement in obesity-related comorbidities (2). Despite advances in surgical techniques, postoperative pain management in bariatric patients remains challenging and may adversely affect early mobilization, respiratory function, and recovery (3). Effective postoperative analgesia is particularly important in this population because obesity-related comorbidities, such as obstructive sleep apnea, limit opioid use and increase the risk of opioid-related adverse events (4). Consequently, ultrasound-guided regional anesthesia techniques have become integral components of multimodal analgesia strategies in bariatric surgery (5,6). Among these techniques, the transversus abdominis plane (TAP) block and the erector spinae plane (ESP) block are commonly used for postoperative pain control after laparoscopic abdominal surgery (7,8). The TAP block primarily provides somatic analgesia of the anterior abdominal wall but may offer limited visceral analgesia and inconsistent coverage of upper thoracic dermatomes in obese patients (9,10). In contrast, the ESP block is thought to allow wider cranio-caudal spread of local anesthetic, potentially providing both somatic and visceral analgesia (11,12). However, comparative data regarding the relative analgesic efficacy of ESP and TAP blocks in obese patients undergoing laparoscopic bariatric surgery remain limited and sometimes conflicting (6,13). Therefore, this study aimed to compare the postoperative analgesic efficacy and safety of ultrasound-guided ESP and TAP blocks in patients undergoing laparoscopic sleeve gastrectomy.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis retrospective observational study was conducted in accordance with the Declaration of Helsinki after approval by the Institutional Research Ethics Committee. Medical records of adult patients who underwent elective laparoscopic sleeve gastrectomy were retrospectively reviewed. Patients were included if they received either an ultrasound-guided transversus abdominis plane (TAP) block or erector spinae plane (ESP) block as part of postoperative analgesia. Patients with incomplete records, conversion to open surgery, or missing postoperative pain assessments were excluded. In our clinic, all patients are given standard general anesthesia with propofol (2.5 mg/kg), fentanyl (2 µg/kg), and rocuronium (0.6 mg/kg) for induction, followed by maintenance anesthesia with sevoflurane (2%) in a 50% oxygen-air mixture. Standard intraoperative monitoring, electrocardiography, non-invasive blood pressure, pulse oximetry, and end-respiratory carbon dioxide monitoring are recorded on the follow-up form. All patients receive standard multimodal analgesia consisting of intravenous paracetamol and nonsteroidal anti-inflammatory drugs, with opioids only used as rescue analgesia. Patients were grouped according to the regional anesthesia technique documented in their medical records. Ultrasound-guided TAP block is applied bilaterally at the end of surgery under aseptic conditions, using a linear ultrasound probe placed in the mid-axillary line between the iliac crest and the costal margin. Local anesthesia is injected into the fascial plane between the internal oblique and transversus abdominis muscles using hydrodissection guided by real-time ultrasound. Ultrasound-guided ESP block is applied bilaterally at the thoracic level. Local anesthesia is injected into the fascial plane deep to the erector spinae muscle at the level of the transverse process. Both blocks are applied using the same local anesthetic mixture, and the total doses do not exceed the recommended safety limits (2 mg/kg).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOutcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe primary outcome was postoperative pain intensity assessed using the Visual Analog Scale (VAS) at predefined time points during the first 24 hours postoperatively. Secondary outcomes included:Distribution of postoperative pain categories, Time to first rescue analgesia, Perioperative hemodynamic parameters, Incidence of postoperative adverse events like bradycardia, hypotension, nausea, vomiting. Given the retrospective design, non-normal distribution of pain scores, and limited sample size, postoperative pain was analyzed using categorical pain distributions rather than continuous VAS values.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eContinuous variables were presented as mean ± standard deviation or median (min–max), and categorical variables as number and percentage. Between-group comparisons were performed using the Mann–Whitney U test for continuous variables and the chi-square or Fisher’s exact test for categorical variables, as appropriate. A p value \u0026lt; 0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 64 patients were included in the final analysis, with 30 patients in the TAP block group and 34 patients in the ESP block group. Demographic characteristics, including age, body weight, height, body mass index, and ASA physical status, were comparable between groups, with no statistically significant differences observed (all p \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIntraoperative and Hemodynamic Data\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDuration of anesthesia, intraoperative fluid administration, and estimated blood loss were similar between the TAP and ESP groups. Mean arterial pressure, heart rate, and oxygen saturation remained stable throughout the perioperative period and did not differ significantly between groups at any measured time point.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePostoperative Pain Outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the post-anesthesia care unit, a higher proportion of patients in the ESP group were pain-free compared with the TAP group; however, this difference did not reach statistical significance.\u003c/p\u003e\n\u003cp\u003eAt postoperative 2 hours, the proportion of pain-free patients was significantly higher in the ESP group than in the TAP group (p \u0026lt; 0.05). At postoperative 6, 12, 24, and 48 hours, pain distribution was comparable between groups, with no statistically significant differences observed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRescue Analgesia and Adverse Events\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTime to first rescue analgesia did not differ significantly between the TAP and ESP groups. Postoperative adverse events, including bradycardia, hypotension, and postoperative nausea and vomiting, were infrequent and comparable between groups. No cases of local anesthetic systemic toxicity or block-related complications were observed.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eAlthough continuous VAS scores are frequently used in postoperative pain studies, in this study pain was analyzed using categorical pain distributions. This approach was chosen to highlight the percentage of pain-free patients, especially in the early postoperative period; this percentage is a significant predictor of patient comfort, mobilization, and satisfaction. Furthermore, categorical analysis is less sensitive to inter-individual variability in pain perception and reporting, which may be more pronounced in obese patients. Given the retrospective design, the non-normal distribution of pain scores, and the relatively small sample size, categorical pain analysis using the chi-square test was considered a more robust and clinically interpretable method. Similar categorical approaches to postoperative pain assessment have been previously used to enhance clinical interpretability in regional anesthesia studies. (16, 17). The principal finding of this study is that the ultrasound-guided erector spinae plane (ESP) block provided superior early postoperative analgesia compared with the transversus abdominis plane (TAP) block in patients undergoing laparoscopic sleeve gastrectomy. This difference was most pronounced during the early postoperative period, particularly at the second postoperative hour, while pain scores at later time points were comparable between the two techniques. These findings support the role of ESP block as an effective component of multimodal analgesia in bariatric surgery. The early analgesic advantage observed with ESP block may be explained by its proposed mechanism of action. Anatomical, cadaveric, and imaging studies suggest that local anesthetic injected into the erector spinae plane can spread cranio-caudally and anteriorly toward the paravertebral and epidural spaces, potentially resulting in blockade of both dorsal and ventral rami as well as sympathetic fibers (11, 12, 18). This broader spread may allow ESP block to provide partial visceral analgesia in addition to somatic analgesia, which is particularly relevant in laparoscopic bariatric surgery where visceral pain contributes significantly to postoperative discomfort. In contrast, the TAP block primarily targets the somatic nerves of the anterior abdominal wall and has limited effect on visceral pain pathways (9, 19). Moreover, in obese patients, increased subcutaneous adipose tissue and altered anatomy may compromise ultrasound visualization and the reliability of local anesthetic spread within the transversus abdominis plane (7, 20). These factors may partially explain the less pronounced early analgesic effect observed with TAP block in the present study. Our findings are consistent with previously published randomized controlled trials comparing ESP and TAP blocks in bariatric and laparoscopic abdominal surgery. Mu et al. demonstrated that ESP block at the T9 level provided superior early postoperative analgesia and improved recovery profiles compared with TAP block in patients undergoing laparoscopic sleeve gastrectomy (6). Similarly, Elshazly et al. reported significantly lower early postoperative pain scores with ESP block following laparoscopic bariatric surgery (13). In addition, recent systematic reviews and meta-analyses have suggested that ESP block may offer improved early analgesic efficacy compared with TAP block, although heterogeneity among studies remains substantial (8,21,22). Despite the early analgesic superiority of ESP block, pain scores beyond the immediate postoperative period were comparable between groups. This finding suggests that both ESP and TAP blocks are effective regional anesthesia techniques when incorporated into a standardized multimodal analgesia regimen. From a clinical perspective, this supports the individualized selection of regional anesthesia techniques based on patient anatomy, surgical characteristics, and practitioner expertise rather than a one-size-fits-all approach (23, 24). Importantly, both techniques demonstrated favorable safety profiles in this high-risk obese population. No cases of local anesthetic systemic toxicity or block-related complications were observed, and perioperative hemodynamic parameters remained stable in both groups. These findings are consistent with previous studies emphasizing the safety of ultrasound-guided fascial plane blocks in bariatric surgery and other high-risk surgical populations (5,7,25). From a practical standpoint, ESP block may offer technical advantages in obese patients due to more reliable ultrasound landmarks, such as the transverse process, compared with the deeper and less distinct fascial planes targeted in TAP block. Although block performance time and technical difficulty were not formally assessed in this study, this observation has been increasingly reported in the literature and may have implications for clinical workflow and block success rates in patients with high body mass index (19,26,27,28). The present study demonstrates that both TAP and ESP blocks provide hemodynamically stable and safe perioperative analgesia in patients undergoing bariatric surgery. The absence of significant differences in cardiovascular and respiratory parameters across all perioperative phases indicates that both regional techniques are well tolerated in this high-risk patient population. From an analgesic perspective, the ESP block showed a distinct advantage in the early postoperative period, particularly at 2 hours after surgery, where a significantly higher proportion of patients were pain-free. This early benefit may be related to the broader dermatomal spread and potential paravertebral or central modulation associated with the ESP block. However, beyond the early postoperative phase, pain control was comparable between groups, suggesting that both techniques provide similar mid- and late-term analgesic efficacy. The low and comparable incidence of adverse events further supports the clinical safety of both blocks. Overall, these findings indicate that while the ESP block may offer superior early postoperative pain control, TAP and ESP blocks have comparable overall effectiveness and safety profiles throughout the postoperative course.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn patients undergoing laparoscopic bariatric surgery, both ultrasound-guided transversus abdominis plane and erector spinae plane blocks provided effective and safe postoperative analgesia as part of a multimodal analgesic regimen, with preserved perioperative hemodynamic stability and a low incidence of adverse events. The erector spinae plane block was associated with superior early postoperative pain control, particularly within the first postoperative hours, whereas analgesic efficacy in the mid- and late postoperative periods was comparable between techniques. These findings suggest that while both blocks represent reliable regional anesthesia options in bariatric surgery, the erector spinae plane block may be preferentially considered when enhanced early postoperative analgesia is desired, without compromising overall safety.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBlair SN, Nichaman MZ. The public health problem of increasing prevalence rates of obesity and what should be done about it. Mayo Clin Proc. 2002 Feb;77(2):109-13. doi: 10.4065/77.2.109.\u003c/li\u003e\n\u003cli\u003eNedelcut S, Axer S, Olbers T. The risk and benefit of revisional vs. primary metabolic- bariatric surgery and drug therapy - A narrative review. Metabolism. 2024 May;154:155799. doi: 10.1016/j.metabol.2024.155799.\u003c/li\u003e\n\u003cli\u003eBaytar \u0026Ccedil;, G\u0026uuml;rb\u0026uuml;z Z, K\u0026ouml;ksal İnceg\u0026uuml;l BG, Baytar MS, Taşd\u0026ouml;ven İ, Pişkin \u0026Ouml;. Effects of modified thoracoabdominal nerves block through pericondrial approach on postoperative pulmonary functions in laparoscopic bariatric surgery: a randomized controlled study. Obes Surg 2025 May 21. doi:10.1007/s11695-025-07908-3.\u003c/li\u003e\n\u003cli\u003eSharma D, Meena S, Anand G. Randomized single blind trial to compare the short term post-operative outcome and cost analysis of laparoscopic versus ultrasound guided transversus abdominis plane block in patients undergoing bariatric surgery. Surg Endosc. 2023 Sep;37(9):7136-7143. doi: 10.1007/s00464-023-10189-5.\u003c/li\u003e\n\u003cli\u003eMartin SP, Etzel J, Aghazarian G, Wert Y, Answine JF, DiMarco L. Perioperative Multimodal Anesthetic Care Incorporating Transversus Abdominis Plane Block Is Associated With Reduced Narcotic Use in Laparoscopic Sleeve Gastrectomy. Am Surg. 2022 Feb;88(2):242-247. doi: 10.1177/0003134820988823.\u003c/li\u003e\n\u003cli\u003eMu T, Chen K, Xu Y, Hao Y, Liu D, Wei K. Comparison Between Erector Spinae Plane Block at T9 Level and Transversus Abdominis Plane Block for Postoperative Analgesia and Recovery in Patients with Obesity Undergoing Laparoscopic Sleeve Gastrectomy: A Randomized Controlled Trial. Obes Surg. 2025 Jun;35(6):2249-2263. doi: 10.1007/s11695-025-07920-7.\u003c/li\u003e\n\u003cli\u003eDe Cassai A, Tulgar S, Carron M, Navalesi P. Regional anesthesia in bariatric surgery. Curr Opin Anaesthesiol 2025 Apr 29. doi:10.1097/ACO.0000000000001506.\u003c/li\u003e\n\u003cli\u003eGao Y, Liu L, Cui Y, Zhang J, Wu X. Postoperative analgesia efficacy of erector spinae plane block in adult abdominal surgery: A systematic review and meta-analysis of randomized trials. Front Med (Lausanne). 2022 Oct 4;9:934866. doi: 10.3389/fmed.2022.934866. \u003c/li\u003e\n\u003cli\u003eBelavy D, Cowlishaw PJ, Howes M, Phillips F. Ultrasound-guided transversus abdominis plane block for analgesia after Caesarean delivery. Br J Anaesth. 2009 Nov;103(5):726-30. doi: 10.1093/bja/aep235.\u003c/li\u003e\n\u003cli\u003eChin KJ, Adhikary S, Sarwani N, Forero M. The analgesic efficacy of pre-operative bilateral erector spinae plane (ESP) blocks in patients having ventral hernia repair. Anaesthesia. 2017 Apr;72(4):452-460. doi: 10.1111/anae.13814.\u003c/li\u003e\n\u003cli\u003eAlbrecht E, Kirkham KR, Liu SS, Brull R, Chin KJ. Transversus abdominis plane block for postoperative analgesia after caesarean delivery: a systematic review and meta-analysis. Br J Anaesth 2013;111:440\u0026ndash;6.\u003c/li\u003e\n\u003cli\u003eStewart MD, Johnson T, Evans W, Harkness H. Bilateral erector spinae plane blocks versus bilateral transversus abdominis plane blocks in patients undergoing abdominal surgery: a systematic review and meta-analysis. AANA J 2023;91:133\u0026ndash;40.\u003c/li\u003e\n\u003cli\u003eElshazly M, El-Wahab NAA, Mostafa M. Erector spinae versus transversus abdominis plane block for postoperative analgesia after laparoscopic bariatric surgery: a randomized controlled trial. Ain-Shams J Anaesthesiol 2022;14:37.\u003c/li\u003e\n\u003cli\u003eForero, M., Rajarathinam, M., Adhikary, S., \u0026amp; Chin, K. J. (2017). Continuous Erector Spinae Plane Block for Rescue Analgesia in Thoracotomy After Epidural Failure: A Case Report. A \u0026amp; A case reports, 8(10), 254\u0026ndash;256. https://doi.org/10.1213/XAA.0000000000000478\u003c/li\u003e\n\u003cli\u003eStewart, M., Tubog, T. D., Johnson, W., \u0026amp; Evans, H. (2023). Bilateral Erector Spinae Plane Blocks versus Bilateral Transversus Abdominis Plane Blocks in Patients Undergoing Abdominal Surgery: A Systematic Review and Meta-Analysis. AANA journal, 91(6), 455\u0026ndash;463.\u003c/li\u003e\n\u003cli\u003eAbdallah, F. W., Brull, R. The definition of block \u0026quot;success\u0026quot; in the contemporary literature: are we speaking the same language?. Regional anesthesia and pain medicine, 37(5), 2012. 545\u0026ndash;553. https://doi.org/10.1097/AAP.0b013e3182583b00\u003c/li\u003e\n\u003cli\u003eAlbrecht, E., Chin, K. J. Advances in regional anaesthesia and acute pain management: a narrative review. Anaesthesia. 75 Suppl 1; 2020, e101\u0026ndash;e110. https://doi.org/10.1111/anae.14868\u003c/li\u003e\n\u003cli\u003eQin Y, Zhou X, Wu M, She H, Wu J. Erector spinae plane block versus quadratus lumborum block for abdominal surgery: A systematic review and meta-analysis. World J Surg. 2025;49(1):204-218. doi:10.1002/wjs.12428\u003c/li\u003e\n\u003cli\u003eJiang, W., Wang, M., Wang, X. et al. Effects of Erector Spinae Plane Block and Transmuscular Quadratus Lumborum Block on Postoperative Opioid Consumption in Total Laparoscopic Hysterectomy: A Randomized Controlled Clinical Trial. Pain Ther 12, 811\u0026ndash;824 (2023). https://doi.org/10.1007/s40122-023-00505-1\u003c/li\u003e\n\u003cli\u003eDe Cassai A, Bonvicini D, Correale C, Sandei L, Tulgar S, Tonetti T. Erector spinae plane block: a systematic qualitative review. Minerva Anestesiol. 2019;85(3):308-319. doi:10.23736/S0375-9393.18.13341-4\u003c/li\u003e\n\u003cli\u003eTulgar, S., Ahiskalioglu, A., De Cassai, A., \u0026amp; Gurkan, Y. (2019). Efficacy of bilateral erector spinae plane block in the management of pain: current insights. Journal of Pain Research, 12, 2597\u0026ndash;2613. https://doi.org/10.2147/JPR.S182128\u003c/li\u003e\n\u003cli\u003eMay PL, Wojcikiewicz T. Regional anaesthesia and fascial plane blocks for abdominal surgery: a narrative review. Dig Med Res 2022;5:42. doi: 10.21037/dmr-21-83\u003c/li\u003e\n\u003cli\u003eCarver, A., Wou, F. \u0026amp; Pawa, A. Do Outcomes Differ Between Thoracic Epidurals and Continuous Fascial Plane Blocks in Adults Undergoing Major Abdominal Surgery?. Curr Anesthesiol Rep 14, 25\u0026ndash;41 (2024). https://doi.org/10.1007/s40140-023-00594-w\u003c/li\u003e\n\u003cli\u003eChin KJ, Malhas L, Perlas A. The Erector Spinae Plane Block Provides Visceral Abdominal Analgesia in Bariatric Surgery: A Report of 3 Cases. Reg Anesth Pain Med. 2017;42(3):372-376. doi:10.1097/AAP.0000000000000581\u003c/li\u003e\n\u003cli\u003eChin KJ, El-Boghdadly K. Mechanisms of action of the erector spinae plane (ESP) block: a narrative review. Mcanismes daction du bloc du plan des muscles recteurs du rachis (erector spinae, ESP) : un compte rendu narratif. Can J Anaesth. 2021;68(3):387-408. doi:10.1007/s12630-020-01875-2\u003c/li\u003e\n\u003cli\u003eStewart JW, Dickson D, Van Hal M, et al. Ultrasound-guided erector spinae plane blocks for pain management after open lumbar laminectomy. Eur Spine J. 2024;33(3):949-955. doi:10.1007/s00586-023-07881-4\u003c/li\u003e\n\u003cli\u003eQian L, Hu N-q, Shen Q-h and Ni K (2025) Comparison of the efficiency of ultrasound-guided ESPB and TAPB on postoperative analgesia: a system review and meta-analysis. Front. Med. 12:1595778. doi: 10.3389/fmed.2025.1595778\u003c/li\u003e\n\u003cli\u003eMansour MA, Baradwan S, Shama AA, et al. Erector spinae plane block versus transversus abdominis plane block for analgesia after cesarean section: a systematic review and meta-analysis. Braz J Anesthesiol. 2025;75(4):844606. doi:10.1016/j.bjane. 2025.844606\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1\u0026nbsp;\u003c/strong\u003eDemographic characteristics, anesthesia-related parameters, intraoperative findings, and early postoperative outcomes of the study population (n = 64).\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMin\u0026ndash;Max\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMedian\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean \u0026plusmn; SD / n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge (years)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e19.0 \u0026ndash; 67.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e32.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e35.2 \u0026plusmn; 11.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeight (kg)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e81.0 \u0026ndash; 184.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e110.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e118.4 \u0026plusmn; 23.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHeight (cm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e142.0 \u0026ndash; 191.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e165.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e166.2 \u0026plusmn; 10.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBody Mass Index (kg/m\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e32.5 \u0026ndash; 52.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e41.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e43.0 \u0026plusmn; 8.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRegional Block Type\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eTAP block\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e30 (46.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eESP block\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e34 (53.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDuration of Anesthesia (min)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e60.0 \u0026ndash; 180.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e80.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e86.4 \u0026plusmn; 21.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntraoperative Fluid (mL)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e400.0 \u0026ndash; 1500.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e700.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e738.3 \u0026plusmn; 182.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntraoperative Blood Loss (mL)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.0 \u0026ndash; 150.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e50.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e51.7 \u0026plusmn; 20.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean Arterial Pressure (mmHg)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e64.0 \u0026ndash; 115.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e90.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e92.5 \u0026plusmn; 11.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHeart Rate (beats/min)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e60.0 \u0026ndash; 100.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e79.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e80.2 \u0026plusmn; 11.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpO₂ (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e72.0 \u0026ndash; 100.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e98.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e97.5 \u0026plusmn; 4.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTime to First Rescue Analgesia (min)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.0 \u0026ndash; 900.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e47.6 \u0026plusmn; 166.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePACU Adverse Events\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eBradycardia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e2 (3.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eHypotension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e4 (6.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eVomiting\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e7 (10.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003em\u0026nbsp;\u003c/sup\u003eMann-whitney u test \u0026nbsp;/ \u003csup\u003eX\u0026sup2;\u0026nbsp;\u003c/sup\u003eKi-kare test (Fischer test)\u003csup\u003e\u0026nbsp;\u0026nbsp;\u003c/sup\u003e \u003csup\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eTable \u0026nbsp;2. Perioperative Hemodynamic Parameters and Postoperative Adverse Events\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTAP (n=30) Mean \u0026plusmn; SD / n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eESP (n=34) Mean \u0026plusmn; SD / n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean Arterial Pressure (mmHg)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e94.6 \u0026plusmn; 10.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e90.6 \u0026plusmn; 12.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.206\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eIntraoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e95.0 \u0026plusmn; 13.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e95.1 \u0026plusmn; 22.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.261\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003ePACU\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e94.3 \u0026plusmn; 9.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e92.2 \u0026plusmn; 11.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.312\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003ePostoperative 24 h\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e94.6 \u0026plusmn; 10.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e91.5 \u0026plusmn; 11.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.178\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHeart Rate (beats/min)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e81.9 \u0026plusmn; 11.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e78.6 \u0026plusmn; 11.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.166\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003ePACU\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e80.6 \u0026plusmn; 16.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e78.2 \u0026plusmn; 14.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.653\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003ePostoperative 24 h\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e83.2 \u0026plusmn; 9.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e80.9 \u0026plusmn; 10.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.309\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpO₂ (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e97.3 \u0026plusmn; 5.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e97.7 \u0026plusmn; 1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.081\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003ePACU\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e97.2 \u0026plusmn; 2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e97.6 \u0026plusmn; 1.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.950\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTime to First Rescue Analgesia (min)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e100.3 \u0026plusmn; 233.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e100.1 \u0026plusmn; 230.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.782\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative Adverse Events\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eBradycardia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e1 (3.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e1 (2.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eHypotension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e2 (6.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e2 (5.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eVomiting (PACU)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e5 (16.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e2 (5.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.168\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eVomiting (2 h)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e6 (20.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e2 (5.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.088\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eVomiting (\u0026ge;6 h)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTable 3. Postoperative Pain Distribution According to Groups\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePain category\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTAP (n=30) n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eESP (n=34) n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePACU\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eNo pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e5 (16.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e13 (38.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0.055\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eVery mild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e15 (50.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e15 (44.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eMild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e8 (26.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e5 (14.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eModerate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e2 (6.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e1 (2.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eSevere\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eNo pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative 2 Hours\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eNo pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e7 (23.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e17 (50.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.028\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eVery mild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e16 (53.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e7 (20.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eMild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e6 (20.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e7 (20.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eModerate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e1 (3.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e2 (5.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eSevere\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e1 (2.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative 6 Hours\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eNo pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e10 (33.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e18 (52.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0.115\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eVery mild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e15 (50.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e12 (35.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eMild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e3 (10.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e3 (8.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eModerate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e2 (6.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eSevere\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e1 (2.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative 12 Hours\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eNo pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e18 (60.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e18 (52.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0.570\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eVery mild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e10 (33.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e13 (38.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eMild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e2 (6.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e3 (8.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eModerate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003eSevere\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative 24 Hours\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eNo pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e20 (66.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e19 (55.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0.378\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eVery mild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e10 (33.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e14 (41.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eMild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e1 (2.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eModerate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eSevere\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative 48 Hours\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eNo pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e21 (70.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e18 (52.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0.163\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eVery mild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e8 (26.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e16 (47.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eMild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e1 (3.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eModerate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003eSevere\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 121px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eChi-square (\u0026chi;\u0026sup2;) test was used for between-group comparisons\u003c/p\u003e\n\u003cp\u003eStatistically significant p values are shown in bold\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"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":"Bariatric surgery, Erector spinae plane block, Transversus abdominis plane block, Postoperative pain, Regional anesthesia","lastPublishedDoi":"10.21203/rs.3.rs-8804510/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8804510/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003ePostoperative pain management in bariatric surgery remains challenging, particularly in patients with obesity-related comorbidities that limit opioid use. Ultrasound-guided regional anesthesia techniques are therefore essential components of multimodal analgesia. Among these, the transversus abdominis plane (TAP) block and the erector spinae plane (ESP) block are commonly used, yet comparative data in bariatric surgery are limited.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eThis retrospective observational study included adult patients who underwent elective laparoscopic sleeve gastrectomy and received either an ultrasound-guided TAP block or ESP block as part of postoperative analgesia. All patients received standardized general anesthesia and multimodal analgesia. Postoperative pain was assessed using the Visual Analog Scale and analyzed as categorical pain distributions at predefined time points. Perioperative hemodynamic parameters, time to first rescue analgesia, and postoperative adverse events were also evaluated.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eA total of 64 patients were analyzed (TAP group, n = 30; ESP group, n = 34). Demographic characteristics, intraoperative variables, and perioperative hemodynamic parameters were comparable between groups. The proportion of pain-free patients was significantly higher in the ESP group at postoperative 2 hours, whereas pain distribution at later time points (6–48 hours) was similar between groups. Time to first rescue analgesia and the incidence of postoperative adverse events did not differ significantly.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eBoth TAP and ESP blocks provided effective and safe postoperative analgesia following laparoscopic bariatric surgery. The ESP block was associated with superior early postoperative pain control, while overall analgesic efficacy and safety profiles were comparable between techniques. ESP block may be preferentially considered when enhanced early postoperative analgesia is desired.\u003c/p\u003e","manuscriptTitle":"Comparison of Ultrasound-Guided Erector Spinae Plane and Transversus Abdominis Plane Blocks for Postoperative Analgesia in Laparoscopic Bariatric Surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-09 09:46:47","doi":"10.21203/rs.3.rs-8804510/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":"1e634ba5-4a5c-4307-86be-8621a1f454aa","owner":[],"postedDate":"February 9th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":62560149,"name":"Surgery"},{"id":62560150,"name":"Anesthesiology \u0026 Pain Medicine"}],"tags":[],"updatedAt":"2026-02-09T09:46:47+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-09 09:46:47","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8804510","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8804510","identity":"rs-8804510","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}