Clinical impact of Enhanced Recovery After Spinal Surgery Protocols on One-Level Lumbar Arthrodesis: Results from a Single-Center Randomized Controlled Trial

Clinical impact of Enhanced Recovery After Spinal Surgery Protocols on One-Level Lumbar Arthrodesis: Results from a Single-Center Randomized Controlled Trial | 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 Clinical impact of Enhanced Recovery After Spinal Surgery Protocols on One-Level Lumbar Arthrodesis: Results from a Single-Center Randomized Controlled Trial Ardavan Kashtiara, Jonah Pauptit, Dieter Thijs, Maxime Verstraeten, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7786792/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 22 Dec, 2025 Read the published version in European Spine Journal → Version 1 posted 9 You are reading this latest preprint version Abstract BACKGROUND AND OBJECTIVES: Enhanced Recovery After Surgery (ERAS) protocols aim to improve surgical outcomes, by mitigating postoperative stress through multimodal perioperative care. In spinal surgery, such protocols—termed Enhanced Recovery After Spine Surgery (ERASS)—may reduce pain, hospital length of stay (LoS), and opioid use. However, prior retrospective studies often suffer from heterogeneity in patient populations and surgical procedures, limiting interpretability. This trial was designed to evaluate the impact of an ERASS protocol on short-term clinical outcomes and LoS in patients undergoing elective single-level lumbar arthrodesis for degenerative spondylolisthesis. METHODS: This single-center, randomized controlled trial included 42 patients allocated to ERASS (n=18) or standard care (n=24). The ERASS protocol included preoperative Gabapentin, early offering of dinner, intraoperative multimodal analgesia, and same-day physiotherapy. Primary outcome was LoS; secondary outcomes included pain at discharge, opioid use, complications, and readmissions. Data were analyzed using univariate statistical tests and multivariable regression models. RESULTS: Median LoS was 3 days in both groups (p=0.685). Pain scores at discharge were lower in the ERASS group (mean 2.5 ± 1.5) versus control (3.1 ± 2.2), though not statistically significant (p=0.079). Multivariate analysis identified World Health Organization (WHO) pain medication level as a significant predictor of LoS (p=0.025), and postoperative nausea and vomiting (PONV) as a predictor of discharge pain (p=0.031). No significant differences were observed in complications or readmission rates. CONCLUSION: While ERASS did not reduce LoS, it trended toward better pain outcomes. Discharge pain and PONV significantly impacted recovery, suggesting these as potential focal points for protocol refinement. Larger, procedure-specific trials with long-term follow-up are warranted. Enhanced Recovery After Surgery (ERAS) Lumbar Athrodesis Degenerative Spondylolisthesis Length of stay Postoperative pain INTRODUCTION Enhanced recovery after surgery (ERAS) protocols are multimodal, evidence-based care pathways developed to attenuate the surgical stress response, reduce complications, accelerate postoperative recovery and reduce hospital stay 1 . Since their initial application in colorectal surgery, ERAS principles have been increasingly implemented across various surgical disciplines, including orthopedic and spinal procedures, where they have demonstrated reduction in length of hospital stay (LoS), opioid requirements and postoperative morbidity without compromising safety or patient satisfaction 2 – 4 . Enhanced recovery after spine surgery (ERASS) protocols are especially formulated because elective spine surgeries are associated with significant postoperative pain and prolonged LoS and recovery time. ERASS is achieved by integrating preoperative patient education, optimized anesthesia, multimodal analgesia, and early mobilization and feeding strategies 4 – 6 . Several studies have concluded that ERASS pathways can improve postoperative outcomes following spine surgery 7 , 8 . However, these studies often compare apples with oranges due to the fact that they include a heterogenous group of indications (degenerative cases, isthmic spondylolisthesis, spinal trauma), clinical diagnoses (e.g. mechanical and non-specific chronic low back pain) as well as both single-level and multi-level spinal surgeries (one- or two level arthrodesis and decompressions). This causes significant bias in interpreting the results. Furthermore, high-quality randomized controlled data remain limited 9 . The present randomized controlled trial (RCT) aims to assess the efficacy of an ERASS protocol in improving short-term clinical outcomes in patients undergoing elective single-level lumbar arthrodesis for degenerative lumbar spondylolisthesis L4-L5. METHODS Study design This single-center, prospective, randomized controlled trial was conducted to evaluate the impact of an Enhanced Recovery After Spinal Surgery (ERASS) protocol on short-term clinical outcomes in patients undergoing one-level (L4-L5) lumbar arthrodesis via open posterior approach. Patient selection A homogenous patient population was chosen to limit confounding factors that are known to influence spinal surgery outcomes. Patients were eligible for inclusion if they were scheduled for elective one-level lumbar arthrodesis for monosegmental degenerative instability at L4-L5 (spondylolisthesis). This had to be confirmed by dynamic lumbar radiographs (minimal 3 mm of slippage) and patients had to have undergone at least six months of conservative treatment (medication, physiotherapy and interventional pain therapy), before undergoing surgery. All patients were treated in the same hospital and by the same surgeon. All patients were over 18 years of age and had to be able to provide oral and written informed consent. Exclusion criteria were: prior spine surgery i.e. revision surgery; indication for surgery being either trauma, tumor or isthmic spondylolisthesis; chronic use of WHO step 3 analgesics (strong opioids); insulin-dependent type 2 diabetes; chronic liver or kidney disease; and cognitive impairment preventing informed consent. Randomization Randomization was manually performed at the preoperative consultations. Patients were handed a sealed envelope containing either a green card (ERASS group) or a red card (control group), which they then presented to the treating anesthesiologist before surgery. This way the surgeon and data collectors could be blinded. Interventions All patients underwent one-level lumbar arthrodesis of the L4-L5 level via an open posterior lumbar interbody arthrodesis procedure. The ERASS protocol group followed a structured pathway. They received physiotherapy twice on the day of surgery, once before and once after. They were to be administered gabapentin 600 mg and 200 mL of apple juice orally 1–2 hours before surgery 10 . For induction S-ketamine, magnesium, solumedrol, diclofenac, sufentanil, propofol and rocuronium were used. S-ketamine, magnesium, sufentanil, sevoflurane and rocuronium were used as maintenance anesthetics. In both groups, corrected body weight was used for determining the dosage of anesthetics. All patients received single dose epidural morphine, paracetamol and droperidol (DHBP) 30 minutes before the end of surgery. Post-operative medical management consisted of paracetamol, diclofenac, piritramide and diazepam. Patients were offered either a yoghurt or a sandwich to stimulate early oral intake after surgery. The control group differed from the ERASS group in a few aspects. Firstly, they did not receive physiotherapy on the day of surgery, nor did they get administered gabapentin and apple juice. For induction sufentanil, propofol, rocuronium and diclofenac were used. For maintenance sufentanil, sevoflurane, rocuronium, epidural morphine, paracetamol and DHBP 30 minutes before the end of surgery was used. After surgery early oral intake was not provided. Further post-operative management was identical to the ERASS group including wound care, early mobilization on postoperative day 1 and physical therapy. Patients were allowed to be discharged if they fulfilled the following requirements: walking without assistance for 15 meters, walking up and down the stairs of one floor and having exercised on the stationary bike. Patients determined whether their pain levels were sufficiently under control with current medication in order to be discharged. No patient was encouraged nor forced to leave the hospital at any given time and no pain scoring system was used as a discharge criterion. Data collection and outcome measures Clinical data were obtained directly from the electronic medical records. The primary outcome measure is length of stay (LoS), defined as the number of days from the day of surgery to hospital discharge. Day of surgery is day 0. The secondary outcomes measures were pain score at discharge and opioid consumption at discharge. The pain score at discharge was defined as the mean pain score of three measurements on the day of discharge using the numeric rating scale (NRS) from 0 (no pain) to 10 (worst imaginable pain). Opioid consumption at discharge was measured using the WHO pain ladder step) with WHO 1 being NSAID/paracetamol and WHO 2 being addition of weak opioids (tramadol). WHO 3 medications (strong opiods) were excluded from this study as previously mentioned and in the postoperative period, so no strong opioids were administered. Variables that were obtained included sex, age in years, smoking status, urinary catheterization, post-operative nausea and vomitus as well as occurrence of perioperative dura laceration, and readmission within 11 days. Sample size calculation A sample size calculation was performed for the continuous variable length of stay (superiority trial, anticipated value ERASS group 3 days, anticipated value control group 4 days with a standard deviation of 1 day, alpha-value 0.05 and 1-Bèta value 0.8) gives a total sample size of 34 to sufficiently detect a change in mean length of stay between the two groups. Our total of n = 42 patients is larger than the calculated 34, so power to detect a 1-day difference in LoS should be at least as good as planned. Statistical analysis Data are presented as mean +/- standard deviation, median (interquartile range / IQR), or frequencies (percentage), when appropriate. Groups were compared with the Pearson Chi-square test for categorical variables, the Mann-Whitney U test for non-normally distributed continuous variables and the independent samples t-test with variance assumed for normally distributed continuous variables. Furthermore, a multicollinearity matrix was generated for assessing significant variables for inclusion or exclusion in the multivariate regression analysis. Finally multivariate regression models were generated for LoS as well as pain score at discharge. Analyses were performed using IBM SPSS statistics software version 29. Ethical considerations The study was approved by the institutional ethics committee. All participants provided written informed consent. The trial was conducted in accordance with the principles of the Declaration of Helsinki. RESULTS ERASS vs. standard care A total of 42 patients were included in the study from October 2021 till March 2025, with 18 (41.9%) in the ERASS group and 24 (55.8%) in the standard care group. Baseline characteristics for both groups are listed in Table 1 . There were no significant demographical differences between the groups in terms of sex (p = .353), smoking status (p = .839) and age (p = .685). Males accounted for 35.7% of the cohort, smokers for 26.2% and the mean age was 59.2 +/- 13.6 years. Table 1 Baseline characteristics and demographics for the ERASS and standard care groups. Primary and secondary outcome measures are listed in Table 2 . Median length of stay (LoS) was comparable across both groups, with a median of 3 days (Interquartile range /IQR ERASS = 2, standard care = 1; p = .255). Pain scores at discharge were lower in the ERASS group (mean = 2.5 +/- 1.5) compared to the standard care group (mean = 3.1 +/- 2.2), although this difference did not reach statistical significance (p = .079). No significant differences were observed in urinary catheterization incidence (p = .351) with 64.3% of patients receiving a temporary indwelling urinary catheter. Use of analgesics at discharge showed no significant difference (p = .417), with most patients discharged on WHO step 1 medications (47.6%) and none on WHO step 3 medication. Readmission rate within 11 days was low (2.4%) and not significantly different between groups (p = .381). The incidence of PONV was comparable between groups (p = .721), as was the rate of dura laceration (p = .381), with one dura laceration occurring in the control group. Variable Total ERASS Standard care P-value Group (n) 42 (100%) 18 (41.9%) 24 (55.8%) - Sex M F 15 (35.7%) 27 (64.3%) 5 (22.7%) 13 (72.2%) 10 (41.7%) 14 (58.3%) .353 Age in years 59.2 +/- 13.6 60.1 +/- 12.1 58.5 +/- 14.9 .685 Smoking No Yes 31 (73.8%) 11 (26.2%) 13 (72.2%) 5 (27.8%) 18 (75%) 6 (25%) .839 Table 2 Primary and secondary clinical outcome measurements for the ERASS and standard care groups. Variable Total Eras Control P-value Length of Stay 3 IQR 1 3 IQR 2 3 IQR 1 .685 Pain scores at discharge (NRS 0–10) 2.8 +/- 1.9 2.5 +/- 1.5 3.1 +/- 2.2 .079 Urinary catheterization Normal miction Single-use Urinary catheter 11 (26.2%) 4 (9.5%) 27 (64.3%) 5 (27.8%) 3 (16.7%) 10 (44.6%) 6 (25%) 1 (4.2%) 17 (63%) .351 WHO pain ladder at discharge No pain meds WHO step 1 WHO step 2 8 (19%) 20 (47.6%) 14 (33.3%) 4 (22.2%) 10 (55.6%) 4 (22.2%) 4 (16.7%) 10 (41.7%) 10 (41.7%) .417 Readmission < 12 days No Yes 41 (97.6%) 1 (2.4%) 18 (100%) 0 (0%) 23 (95.8%) 1 (4.2%) .381 PONV No Yes 22 (52.4%) 20 (47.6%) 10 (55.6%) 8 (44.4%) 12 (50%) 12 (50%) .721 Complication No Dura laceration 41 (97.6%) 1 (2.4%) 18 (100%) 0 (0%) 23 (95.8%) 1 (4.2%) .381 Multivariable regression analyses LoS A series of linear regression models were conducted to identify predictors of LoS. These can be found in Table 3 . In the first model, age, ERASS group, urinary catheterization, and WHO pain ladder scores at discharge were included as predictors based on clinical likelihood as well as the multicollinearity matrix. The model explains 22.2% of the variance in LoS (R = 0.471, R 2 = 0.22, Adjusted R 2 = 0.138; ANOVA p = .049), indicating moderate predictive power. Among the variables, only the WHO pain ladder score at discharge was a statistically significant predictor (B = 0.96, P = 0.025), suggesting that for each one-step increase in the WHO pain ladder, LoS increased by approximately 0.96 days. Age showed a non-significant positive trend (B = 0.033, p = .137), while ERASS group, urinary catheterization did not significantly affect LoS (p = .379 and p = .438, respectively). No multicollinearity was observed, with variance inflation factors all below 1.1. Subsequent models further confirmed the association between WHO pain ladder medication use and LoS. Table 3 Linear regression results predicting LoS Predictor B SE β t p-value VIF (Constant) 0.550 1.338 — 0.411 .684 — Age (years) 0.033 0.021 0.228 1.521 .137 1.069 ERAS Group (vs. Control) 0.516 0.580 0.132 0.890 .379 1.052 Urinary Catheterization -0.254 0.325 -0.115 -0.783 .438 1.023 WHO Pain Ladder at Discharge 0.963 0.413 0.354 2.330 .025 1.099 Pain scores at discharge A separate regression analysis was conducted to examine predictors of pain scores at discharge, including age, sex, ERASS group, and the presence of PONV. See Table 4 . The inclusion and exclusion of variables was based on clinical likelihood and the results of the multicollinearity matrix. The model was statistically significant (F (4, 37) = 2.906, p = .035), explaining 23.9% of the variance in pain scores (R 2 = 0.239). Among the predictors, only PONV was statistically significant (B = 1.233, p = .031) indicating that patients experiencing PONV reported pain scores that were on average 1.23 points higher at discharge. ERAS protocol assignment (p = .243), age (p = .252), and sex (p = .217) did not significantly predict discharge pain scores. No multicollinearity was detected among the predictors. Table 4 Linear regression results predicting pain scores at discharge Predictor B SE β t p-value VIF (Constant) 0.646 1.233 — 0.524 .604 — Age (years) 0.024 0.021 0.172 1.164 .252 1.058 Sex (Male = 1) 0.724 0.577 0.185 1.256 .217 1.056 ERAS Group (vs. Control) -0.655 0.552 -0.173 -1.188 .243 1.029 PONV (Yes = 1) 1.233 0.551 0.328 2.236 .031 1.048 DISCUSSION This randomized controlled trial assessed the efficacy of an Enhanced Recovery After Spinal Surgery (ERASS) protocol in patients undergoing single-level lumbar arthrodesis for degenerative spondylolisthesis at L4-L5. The primary outcome—length of stay (LoS)—did not differ significantly between the ERASS and standard care groups (median 3 days in both; p = .685). This finding contrasts with several previous studies suggesting that ERAS protocols reduce LoS in patients undergoing lumbar arthrodesis 11 – 13 . However, Smith et al. also did not find a difference in LoS in their retrospective analysis of one- and two level lumbar arthrodesis 14 . One potential explanation for this discrepancy is the strict discharge criteria applied in our study: all patients were discharged only after meeting predefined clinical benchmarks, regardless of group allocation and they were not forced nor encouraged to leave the hospital. Unlike retrospective studies where discharge timing may be influenced by the intent to adhere to ERAS principles, our design minimized subjective discharge decisions, thereby reducing bias. The similarity of standard care practices and ERASS principles in modern spine centers—such as routine early mobilization and multimodal analgesia—may attenuate the observable incremental benefit of a formal ERASS pathway. This raises the question of whether ERASS protocols retain added value when embedded within already-optimized surgical environments. Additionally, prior studies often include heterogeneous populations, with varying surgical indications (e.g., degenerative vs. isthmic spondylolisthesis) and multi-level procedures, which introduce confounding variables. In contrast, our study exclusively enrolled patients undergoing single-level arthrodesis for degenerative spondylolisthesis at one level, in one center and by one surgeon, thereby reducing heterogeneity and improving internal validity. Finally, multivariable regression analysis revealed that the only significant predictor of LoS was the level of pain medication required at discharge, as measured by the WHO pain ladder. This suggests that residual postoperative pain, rather than the perioperative care pathway itself, may play a more central role in determining hospital discharge timing. Secondary outcomes demonstrated a non-significant trend toward lower pain scores at discharge in the ERASS group ( p = .079), potentially reflecting the benefits of preoperative gabapentin administration and intraoperative multimodal analgesia. While this difference did not reach statistical significance, it may still carry clinical relevance—particularly in the context of patient comfort and efforts to reduce opioid consumption. Notably, a retrospective study by Easton et al. reported significantly lower average pain scores in patients managed under an ERASS protocol compared to those receiving standard care, supporting the potential analgesic benefits of such pathways 15 . Regression analysis identified postoperative nausea and vomiting (PONV) as a significant predictor of discharge pain scores ( p = .031). The association between PONV and higher discharge pain scores may reflect shared underlying neurochemical pathways, such as increased central sensitization or opioid-induced nausea. This finding supports ongoing efforts to reduce opioid exposure perioperatively as a strategy to simultaneously minimize pain and nausea. Importantly, no significant differences were observed between the ERASS and standard care groups in terms of urinary catheterization, readmission rates, or perioperative complications, further supporting the safety and feasibility of the ERASS protocol in this patient population. While ERASS pathways have shown benefits across various surgical specialties—including spine surgery—high-quality, indication-specific randomized controlled trials remain limited. Our findings offer detailed insights into the impact of ERASS within a homogenous surgical population, compared to outcomes achieved with our standard protocol based on current best medical practice. This study has several strengths, including its randomized design, well-defined inclusion criteria, and focus on a homogenous surgical population, all of which enhance internal validity and minimize confounding—common limitations in much of the existing ERASS literature. Nonetheless, several limitations warrant consideration. First, the relatively small sample size ( n = 42) limits the statistical power to detect small to moderate effects. This constraint resulted from the narrow inclusion criteria, intentionally designed to ensure population homogeneity. Given the limited sample size, the absence of statistical significance in several outcomes may reflect a Type II error. The observed trends—such as lower discharge pain scores in the ERASS group—may become significant in larger, adequately powered studies, suggesting a clinically relevant effect currently masked by sample constraints. Second, blinding was only partial, as the anesthesiology team was aware of group assignments, which may have introduced performance bias. Third, while key short-term clinical outcomes such as postoperative pain and LoS were evaluated, the study did not assess longer-term outcomes such as functional recovery, patient satisfaction, or cost-effectiveness as well as bone quality and BMI—all of which are important metrics for comprehensively evaluating the clinical utility of ERASS protocols. CONCLUSION While the ERASS protocol did not significantly reduce hospital length of stay in this RCT of single-level lumbar arthrodesis, it was associated with a trend toward improved postoperative pain control. Multivariate analysis suggests that discharge pain and PONV significantly influence short-term recovery outcomes. These findings highlight the complexity of evaluating ERAS protocols and underscore the need for larger, adequately powered studies focusing on procedure-specific ERAS components. In future research, integration of patient-reported outcomes and long-term follow-up may offer more comprehensive evaluation of ERASS efficacy. Abbreviations ANOVA Analysis of Variance DHBP Dihydroergotamine, Betamethasone, and Paracetamol ERAS Enhanced Recovery After Surgery ERASS Enhanced Recovery After Spinal Surgery IQR Interquartile Range LoS Length of Stay NRS Numeric Rating Scale PONV Postoperative Nausea and Vomiting RCT Randomized Controlled Trial SE Standard Error VIF Variance Inflation Factor WHO World Health Organization Declarations Author Contribution Conceptualization, E.V.D.K, M.V, C.S and P.V; writing—original draft preparation, A.K and J.P.; writing—review and editing, A.K, J.P, D.T and E.V.D.K. All authors have read and agreed to the published version of the manuscript.” Data Availability Available upon request References Jain V, Irrinki S, Khare S et al (2024) Implementation of modified enhanced recovery after surgery (ERAS) following surgery for abdominal trauma; Assessment of feasibility and outcomes: A randomized controlled trial (RCT). Am J Surg 238:115975 Ljungqvist O, Scott M, Fearon KC (2017) Enhanced Recovery After Surgery: A Review. JAMA Surg 152(3):292–298 Soffin EM, YaDeau JT (2016) Enhanced recovery after surgery for primary hip and knee arthroplasty: a review of the evidence. Br J Anaesth 117(suppl 3):iii62–iii72 Debono B, Wainwright TW, Wang MY, et al. Consensus statement for perioperative care in lumbar spinal fusion: Enhanced Recovery After Surgery (ERAS®) Society recommendations. The Spine Journal. 2021;21(5):729–752 Elsarrag M, Soldozy S, Patel P et al (2019) Enhanced recovery after spine surgery: a systematic review. Neurosurg Focus 46(4):E3 Singh K, Bohl DD, Ahn J et al (2017) Multimodal Analgesia Versus Intravenous Patient-Controlled Analgesia for Minimally Invasive Transforaminal Lumbar Interbody Fusion Procedures. Spine (Phila Pa 1976) 42(15):1145–1150 Sivaganesan A, Wick JB, Chotai S, Cherkesky C, Stephens BF, Devin CJ (2019) Perioperative Protocol for Elective Spine Surgery Is Associated With Reduced Length of Stay and Complications. J Am Acad Orthop Surg 27(5):183–189 Choi JU, Kee T-H, Lee D-H, Hwang CJ, Park S, Cho JH (2024) Enhanced Recovery After Surgery Protocols in One- or Two-Level Posterior Lumbar Fusion: Improving Postoperative Outcomes. J Clin Med 13(20). 10.3390/jcm13206285 Naftalovich R, Singal A, Iskander AJ (2022) Enhanced Recovery After Surgery (ERAS) protocols for spine surgery - review of literature. Anaesthesiol Intensive Ther 54(1):71–79 Liu B, Liu R, Wang L (2017) A meta-analysis of the preoperative use of gabapentinoids for the treatment of acute postoperative pain following spinal surgery. Med (Baltim) 96(37):e8031 Duojun W, Hui Z, Zaijun L, Yuxiang G, Haihong C (2021) Enhanced recovery after surgery pathway reduces the length of hospital stay without additional complications in lumbar disc herniation treated by percutaneous endoscopic transforaminal discectomy. J Orthop Surg Res 16(1):461 Yao Y-C, Liou J-Y, Wang H-Y, Chou P-H, Lin H-H, Wang S-T Benefits of early recovery after surgery (ERAS) protocols on perioperative outcomes in patients undergoing elective lumbar spinal fusion: a prospective study. The Spine Journal Han D, Wang P, Kong C, Chen X, Lu S (2024) Enhanced recovery after surgery (ERAS) improves outcomes in elderly patients undergoing short-level lumbar fusion surgery: a retrospective study of 333 cases. Eur J Med Res 29(1):513 Smith J, Probst S, Calandra C et al (2019) Enhanced recovery after surgery (ERAS) program for lumbar spine fusion. Perioperative Med 8(1):4 Easton RW, Lipphardt M, Papakonstantinou NS et al (2022) P67. ERAS protocol associated with improved measurable outcomes in patients undergoing lumbar spinal fusion. Spine J 22(9):S158 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 22 Dec, 2025 Read the published version in European Spine Journal → Version 1 posted Editorial decision: Revision requested 16 Oct, 2025 Reviews received at journal 15 Oct, 2025 Reviews received at journal 14 Oct, 2025 Reviewers agreed at journal 14 Oct, 2025 Reviewers agreed at journal 14 Oct, 2025 Reviewers invited by journal 13 Oct, 2025 Editor assigned by journal 06 Oct, 2025 Submission checks completed at journal 06 Oct, 2025 First submitted to journal 05 Oct, 2025 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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17:30:21","extension":"html","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":69980,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7786792/v1/2ad4c9ad104f48edad1c3973.html"},{"id":99172450,"identity":"8fc99039-efa4-4871-bf42-4cdc7496a505","added_by":"auto","created_at":"2025-12-29 16:09:38","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":649199,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7786792/v1/a18ebb0d-6f7e-4761-a784-7e7d00b6ad64.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Clinical impact of Enhanced Recovery After Spinal Surgery Protocols on One-Level Lumbar Arthrodesis: Results from a Single-Center Randomized Controlled Trial","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eEnhanced recovery after surgery (ERAS) protocols are multimodal, evidence-based care pathways developed to attenuate the surgical stress response, reduce complications, accelerate postoperative recovery and reduce hospital stay \u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. Since their initial application in colorectal surgery, ERAS principles have been increasingly implemented across various surgical disciplines, including orthopedic and spinal procedures, where they have demonstrated reduction in length of hospital stay (LoS), opioid requirements and postoperative morbidity without compromising safety or patient satisfaction \u003csup\u003e\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. Enhanced recovery after spine surgery (ERASS) protocols are especially formulated because elective spine surgeries are associated with significant postoperative pain and prolonged LoS and recovery time. ERASS is achieved by integrating preoperative patient education, optimized anesthesia, multimodal analgesia, and early mobilization and feeding strategies \u003csup\u003e\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e. Several studies have concluded that ERASS pathways can improve postoperative outcomes following spine surgery \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e,\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e. However, these studies often compare apples with oranges due to the fact that they include a heterogenous group of indications (degenerative cases, isthmic spondylolisthesis, spinal trauma), clinical diagnoses (e.g. mechanical and non-specific chronic low back pain) as well as both single-level and multi-level spinal surgeries (one- or two level arthrodesis and decompressions). This causes significant bias in interpreting the results. Furthermore, high-quality randomized controlled data remain limited \u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eThe present randomized controlled trial (RCT) aims to assess the efficacy of an ERASS protocol in improving short-term clinical outcomes in patients undergoing elective single-level lumbar arthrodesis for degenerative lumbar spondylolisthesis L4-L5.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy design\u003c/h2\u003e\u003cp\u003eThis single-center, prospective, randomized controlled trial was conducted to evaluate the impact of an Enhanced Recovery After Spinal Surgery (ERASS) protocol on short-term clinical outcomes in patients undergoing one-level (L4-L5) lumbar arthrodesis via open posterior approach.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003ePatient selection\u003c/h3\u003e\n\u003cp\u003eA homogenous patient population was chosen to limit confounding factors that are known to influence spinal surgery outcomes. Patients were eligible for inclusion if they were scheduled for elective one-level lumbar arthrodesis for monosegmental degenerative instability at L4-L5 (spondylolisthesis). This had to be confirmed by dynamic lumbar radiographs (minimal 3 mm of slippage) and patients had to have undergone at least six months of conservative treatment (medication, physiotherapy and interventional pain therapy), before undergoing surgery. All patients were treated in the same hospital and by the same surgeon. All patients were over 18 years of age and had to be able to provide oral and written informed consent. Exclusion criteria were: prior spine surgery i.e. revision surgery; indication for surgery being either trauma, tumor or isthmic spondylolisthesis; chronic use of WHO step 3 analgesics (strong opioids); insulin-dependent type 2 diabetes; chronic liver or kidney disease; and cognitive impairment preventing informed consent.\u003c/p\u003e\n\u003ch3\u003eRandomization\u003c/h3\u003e\n\u003cp\u003eRandomization was manually performed at the preoperative consultations. Patients were handed a sealed envelope containing either a green card (ERASS group) or a red card (control group), which they then presented to the treating anesthesiologist before surgery. This way the surgeon and data collectors could be blinded.\u003c/p\u003e\n\u003ch3\u003eInterventions\u003c/h3\u003e\n\u003cp\u003e\u003cb\u003eAll patients underwent\u003c/b\u003e one-level lumbar arthrodesis of the L4-L5 level via an open posterior lumbar interbody arthrodesis procedure.\u003c/p\u003e\u003cp\u003eThe ERASS protocol group followed a structured pathway. They received physiotherapy twice on the day of surgery, once before and once after. They were to be administered gabapentin 600 mg and 200 mL of apple juice orally 1\u0026ndash;2 hours before surgery \u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e. For induction S-ketamine, magnesium, solumedrol, diclofenac, sufentanil, propofol and rocuronium were used. S-ketamine, magnesium, sufentanil, sevoflurane and rocuronium were used as maintenance anesthetics. In both groups, corrected body weight was used for determining the dosage of anesthetics. All patients received single dose epidural morphine, paracetamol and droperidol (DHBP) 30 minutes before the end of surgery. Post-operative medical management consisted of paracetamol, diclofenac, piritramide and diazepam. Patients were offered either a yoghurt or a sandwich to stimulate early oral intake after surgery.\u003c/p\u003e\u003cp\u003eThe control group differed from the ERASS group in a few aspects. Firstly, they did not receive physiotherapy on the day of surgery, nor did they get administered gabapentin and apple juice. For induction sufentanil, propofol, rocuronium and diclofenac were used. For maintenance sufentanil, sevoflurane, rocuronium, epidural morphine, paracetamol and DHBP 30 minutes before the end of surgery was used. After surgery early oral intake was not provided.\u003c/p\u003e\u003cp\u003eFurther post-operative management was identical to the ERASS group including wound care, early mobilization on postoperative day 1 and physical therapy.\u003c/p\u003e\u003cp\u003ePatients were allowed to be discharged if they fulfilled the following requirements: walking without assistance for 15 meters, walking up and down the stairs of one floor and having exercised on the stationary bike. Patients determined whether their pain levels were sufficiently under control with current medication in order to be discharged. No patient was encouraged nor forced to leave the hospital at any given time and no pain scoring system was used as a discharge criterion.\u003c/p\u003e\n\u003ch3\u003eData collection and outcome measures\u003c/h3\u003e\n\u003cp\u003eClinical data were obtained directly from the electronic medical records. The primary outcome measure is length of stay (LoS), defined as the number of days from the day of surgery to hospital discharge. Day of surgery is day 0. The secondary outcomes measures were pain score at discharge and opioid consumption at discharge. The pain score at discharge was defined as the mean pain score of three measurements on the day of discharge using the numeric rating scale (NRS) from 0 (no pain) to 10 (worst imaginable pain). Opioid consumption at discharge was measured using the WHO pain ladder step) with WHO 1 being NSAID/paracetamol and WHO 2 being addition of weak opioids (tramadol). WHO 3 medications (strong opiods) were excluded from this study as previously mentioned and in the postoperative period, so no strong opioids were administered. Variables that were obtained included sex, age in years, smoking status, urinary catheterization, post-operative nausea and vomitus as well as occurrence of perioperative dura laceration, and readmission within 11 days.\u003c/p\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eSample size calculation\u003c/h2\u003e\u003cp\u003eA sample size calculation was performed for the continuous variable length of stay (superiority trial, anticipated value ERASS group 3 days, anticipated value control group 4 days with a standard deviation of 1 day, alpha-value 0.05 and 1-B\u0026egrave;ta value 0.8) gives a total sample size of 34 to sufficiently detect a change in mean length of stay between the two groups. Our total of n\u0026thinsp;=\u0026thinsp;42 patients is larger than the calculated 34, so power to detect a 1-day difference in LoS should be at least as good as planned.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eData are presented as mean +/- standard deviation, median (interquartile range / IQR), or frequencies (percentage), when appropriate. Groups were compared with the Pearson Chi-square test for categorical variables, the Mann-Whitney U test for non-normally distributed continuous variables and the independent samples t-test with variance assumed for normally distributed continuous variables. Furthermore, a multicollinearity matrix was generated for assessing significant variables for inclusion or exclusion in the multivariate regression analysis. Finally multivariate regression models were generated for LoS as well as pain score at discharge. Analyses were performed using IBM SPSS statistics software version 29.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eEthical considerations\u003c/h3\u003e\n\u003cp\u003e The study was approved by the institutional ethics committee. All participants provided written informed consent. The trial was conducted in accordance with the principles of the Declaration of Helsinki.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eERASS vs. standard care\u003c/h2\u003e\u003cp\u003eA total of 42 patients were included in the study from October 2021 till March 2025, with 18 (41.9%) in the ERASS group and 24 (55.8%) in the standard care group. Baseline characteristics for both groups are listed in Table\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. There were no significant demographical differences between the groups in terms of sex (p\u0026thinsp;=\u0026thinsp;.353), smoking status (p\u0026thinsp;=\u0026thinsp;.839) and age (p\u0026thinsp;=\u0026thinsp;.685). Males accounted for 35.7% of the cohort, smokers for 26.2% and the mean age was 59.2 +/- 13.6 years.\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\u003eBaseline characteristics and demographics for the ERASS and standard care groups. Primary and secondary outcome measures are listed in Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Median length of stay (LoS) was comparable across both groups, with a median of 3 days (Interquartile range /IQR ERASS\u0026thinsp;=\u0026thinsp;2, standard care\u0026thinsp;=\u0026thinsp;1; p\u0026thinsp;=\u0026thinsp;.255). Pain scores at discharge were lower in the ERASS group (mean\u0026thinsp;=\u0026thinsp;2.5 +/- 1.5) compared to the standard care group (mean\u0026thinsp;=\u0026thinsp;3.1 +/- 2.2), although this difference did not reach statistical significance (p\u0026thinsp;=\u0026thinsp;.079). No significant differences were observed in urinary catheterization incidence (p\u0026thinsp;=\u0026thinsp;.351) with 64.3% of patients receiving a temporary indwelling urinary catheter. Use of analgesics at discharge showed no significant difference (p\u0026thinsp;=\u0026thinsp;.417), with most patients discharged on WHO step 1 medications (47.6%) and none on WHO step 3 medication. Readmission rate within 11 days was low (2.4%) and not significantly different between groups (p\u0026thinsp;=\u0026thinsp;.381). The incidence of PONV was comparable between groups (p\u0026thinsp;=\u0026thinsp;.721), as was the rate of dura laceration (p\u0026thinsp;=\u0026thinsp;.381), with one dura laceration occurring in the control group.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"9\"\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\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eERASS\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\u003cp\u003eStandard care\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e\u003cp\u003eP-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e\u003cp\u003eGroup (n)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e42 (100%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e18 (41.9%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\u003cp\u003e24 (55.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM\u003c/p\u003e\u003cp\u003eF\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003e15 (35.7%)\u003c/p\u003e\u003cp\u003e27 (64.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e5 (22.7%)\u003c/p\u003e\u003cp\u003e13 (72.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e10 (41.7%)\u003c/p\u003e\u003cp\u003e14 (58.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c8\" namest=\"c7\"\u003e\u003cp\u003e.353\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eAge in years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003e59.2 +/- 13.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e60.1 +/- 12.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e58.5 +/- 14.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c8\" namest=\"c7\"\u003e\u003cp\u003e.685\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSmoking\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003e31 (73.8%)\u003c/p\u003e\u003cp\u003e11 (26.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e13 (72.2%)\u003c/p\u003e\u003cp\u003e5 (27.8%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e18 (75%)\u003c/p\u003e\u003cp\u003e6 (25%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c8\" namest=\"c7\"\u003e\u003cp\u003e.839\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"1\" nameend=\"c9\" namest=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\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\u003ePrimary and secondary clinical outcome measurements for the ERASS and standard care groups.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\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\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eEras\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eP-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eLength of Stay\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3 IQR 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3 IQR 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3 IQR 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.685\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003ePain scores at discharge (NRS 0\u0026ndash;10)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.8 +/- 1.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.5 +/- 1.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3.1 +/- 2.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.079\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eUrinary catheterization\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNormal miction\u003c/p\u003e\u003cp\u003eSingle-use\u003c/p\u003e\u003cp\u003eUrinary catheter\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e11 (26.2%)\u003c/p\u003e\u003cp\u003e4 (9.5%)\u003c/p\u003e\u003cp\u003e27 (64.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5 (27.8%)\u003c/p\u003e\u003cp\u003e3 (16.7%)\u003c/p\u003e\u003cp\u003e10 (44.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6 (25%)\u003c/p\u003e\u003cp\u003e1 (4.2%)\u003c/p\u003e\u003cp\u003e17 (63%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.351\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWHO pain ladder at discharge\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo pain meds\u003c/p\u003e\u003cp\u003eWHO step 1\u003c/p\u003e\u003cp\u003eWHO step 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8 (19%)\u003c/p\u003e\u003cp\u003e20 (47.6%)\u003c/p\u003e\u003cp\u003e14 (33.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4 (22.2%)\u003c/p\u003e\u003cp\u003e10 (55.6%)\u003c/p\u003e\u003cp\u003e4 (22.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e4 (16.7%)\u003c/p\u003e\u003cp\u003e10 (41.7%)\u003c/p\u003e\u003cp\u003e10 (41.7%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.417\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eReadmission\u0026thinsp;\u0026lt;\u0026thinsp;12 days\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e41 (97.6%)\u003c/p\u003e\u003cp\u003e1 (2.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e18 (100%)\u003c/p\u003e\u003cp\u003e0 (0%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e23 (95.8%)\u003c/p\u003e\u003cp\u003e1 (4.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.381\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePONV\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e22 (52.4%)\u003c/p\u003e\u003cp\u003e20 (47.6%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10 (55.6%)\u003c/p\u003e\u003cp\u003e8 (44.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e12 (50%)\u003c/p\u003e\u003cp\u003e12 (50%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.721\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComplication\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003cp\u003eDura laceration\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e41 (97.6%)\u003c/p\u003e\u003cp\u003e1 (2.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e18 (100%)\u003c/p\u003e\u003cp\u003e0 (0%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e23 (95.8%)\u003c/p\u003e\u003cp\u003e1 (4.2%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.381\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003eMultivariable regression analyses\u003c/h2\u003e\u003cdiv id=\"Sec14\" class=\"Section3\"\u003e\u003ch2\u003eLoS\u003c/h2\u003e\u003cp\u003eA series of linear regression models were conducted to identify predictors of LoS. These can be found in Table \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. In the first model, age, ERASS group, urinary catheterization, and WHO pain ladder scores at discharge were included as predictors based on clinical likelihood as well as the multicollinearity matrix. The model explains 22.2% of the variance in LoS (R\u0026thinsp;=\u0026thinsp;0.471, R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.22, Adjusted R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.138; ANOVA p\u0026thinsp;=\u0026thinsp;.049), indicating moderate predictive power. Among the variables, only the WHO pain ladder score at discharge was a statistically significant predictor (B\u0026thinsp;=\u0026thinsp;0.96, P\u0026thinsp;=\u0026thinsp;0.025), suggesting that for each one-step increase in the WHO pain ladder, LoS increased by approximately 0.96 days. Age showed a non-significant positive trend (B\u0026thinsp;=\u0026thinsp;0.033, p\u0026thinsp;=\u0026thinsp;.137), while ERASS group, urinary catheterization did not significantly affect LoS (p\u0026thinsp;=\u0026thinsp;.379 and p\u0026thinsp;=\u0026thinsp;.438, respectively). No multicollinearity was observed, with variance inflation factors all below 1.1. Subsequent models further confirmed the association between WHO pain ladder medication use and LoS.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eLinear regression results predicting LoS\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\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\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePredictor\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSE\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eβ\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003et\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eVIF\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e(Constant)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.550\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.338\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026mdash;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.411\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.684\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u0026mdash;\u003c/p\u003e\u003c/td\u003e\u003c/tr\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\u003e0.033\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.021\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.228\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.521\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.137\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.069\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eERAS Group (vs. Control)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.516\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.580\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.132\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.890\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.379\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.052\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eUrinary Catheterization\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-0.254\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.325\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-0.115\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-0.783\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.438\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.023\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWHO Pain Ladder at Discharge\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.963\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.413\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.354\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.330\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e.025\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.099\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\u003ch2\u003ePain scores at discharge\u003c/h2\u003e\u003cp\u003eA separate regression analysis was conducted to examine predictors of pain scores at discharge, including age, sex, ERASS group, and the presence of PONV. See Table \u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. The inclusion and exclusion of variables was based on clinical likelihood and the results of the multicollinearity matrix. The model was statistically significant (F (4, 37)\u0026thinsp;=\u0026thinsp;2.906, p\u0026thinsp;=\u0026thinsp;.035), explaining 23.9% of the variance in pain scores (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.239). Among the predictors, only PONV was statistically significant (B\u0026thinsp;=\u0026thinsp;1.233, p\u0026thinsp;=\u0026thinsp;.031) indicating that patients experiencing PONV reported pain scores that were on average 1.23 points higher at discharge. ERAS protocol assignment (p\u0026thinsp;=\u0026thinsp;.243), age (p\u0026thinsp;=\u0026thinsp;.252), and sex (p\u0026thinsp;=\u0026thinsp;.217) did not significantly predict discharge pain scores. No multicollinearity was detected among the predictors.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eLinear regression results predicting pain scores at discharge\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\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\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePredictor\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSE\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eβ\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003et\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003ep-value\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eVIF\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e(Constant)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.646\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.233\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026mdash;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.524\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.604\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u0026mdash;\u003c/p\u003e\u003c/td\u003e\u003c/tr\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\u003e0.024\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.021\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.172\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.164\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.252\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.058\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex (Male\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.724\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.577\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.185\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.256\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.217\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.056\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eERAS Group (vs. Control)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-0.655\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.552\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-0.173\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.188\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e.243\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.029\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePONV (Yes\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.233\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.551\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.328\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.236\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e.031\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.048\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThis randomized controlled trial assessed the efficacy of an Enhanced Recovery After Spinal Surgery (ERASS) protocol in patients undergoing single-level lumbar arthrodesis for degenerative spondylolisthesis at L4-L5.\u003c/p\u003e\u003cp\u003eThe primary outcome\u0026mdash;length of stay (LoS)\u0026mdash;did not differ significantly between the ERASS and standard care groups (median 3 days in both; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.685). This finding contrasts with several previous studies suggesting that ERAS protocols reduce LoS in patients undergoing lumbar arthrodesis \u003csup\u003e\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. However, Smith et al. also did not find a difference in LoS in their retrospective analysis of one- and two level lumbar arthrodesis \u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. One potential explanation for this discrepancy is the strict discharge criteria applied in our study: all patients were discharged only after meeting predefined clinical benchmarks, regardless of group allocation and they were not forced nor encouraged to leave the hospital. Unlike retrospective studies where discharge timing may be influenced by the intent to adhere to ERAS principles, our design minimized subjective discharge decisions, thereby reducing bias. The similarity of standard care practices and ERASS principles in modern spine centers\u0026mdash;such as routine early mobilization and multimodal analgesia\u0026mdash;may attenuate the observable incremental benefit of a formal ERASS pathway. This raises the question of whether ERASS protocols retain added value when embedded within already-optimized surgical environments. Additionally, prior studies often include heterogeneous populations, with varying surgical indications (e.g., degenerative vs. isthmic spondylolisthesis) and multi-level procedures, which introduce confounding variables. In contrast, our study exclusively enrolled patients undergoing single-level arthrodesis for degenerative spondylolisthesis at one level, in one center and by one surgeon, thereby reducing heterogeneity and improving internal validity.\u003c/p\u003e\u003cp\u003eFinally, multivariable regression analysis revealed that the only significant predictor of LoS was the level of pain medication required at discharge, as measured by the WHO pain ladder. This suggests that residual postoperative pain, rather than the perioperative care pathway itself, may play a more central role in determining hospital discharge timing.\u003c/p\u003e\u003cp\u003eSecondary outcomes demonstrated a non-significant trend toward lower pain scores at discharge in the ERASS group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.079), potentially reflecting the benefits of preoperative gabapentin administration and intraoperative multimodal analgesia. While this difference did not reach statistical significance, it may still carry clinical relevance\u0026mdash;particularly in the context of patient comfort and efforts to reduce opioid consumption. Notably, a retrospective study by Easton et al. reported significantly lower average pain scores in patients managed under an ERASS protocol compared to those receiving standard care, supporting the potential analgesic benefits of such pathways \u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eRegression analysis identified postoperative nausea and vomiting (PONV) as a significant predictor of discharge pain scores (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.031). The association between PONV and higher discharge pain scores may reflect shared underlying neurochemical pathways, such as increased central sensitization or opioid-induced nausea. This finding supports ongoing efforts to reduce opioid exposure perioperatively as a strategy to simultaneously minimize pain and nausea. Importantly, no significant differences were observed between the ERASS and standard care groups in terms of urinary catheterization, readmission rates, or perioperative complications, further supporting the safety and feasibility of the ERASS protocol in this patient population.\u003c/p\u003e\u003cp\u003eWhile ERASS pathways have shown benefits across various surgical specialties\u0026mdash;including spine surgery\u0026mdash;high-quality, indication-specific randomized controlled trials remain limited. Our findings offer detailed insights into the impact of ERASS within a homogenous surgical population, compared to outcomes achieved with our standard protocol based on current best medical practice.\u003c/p\u003e\u003cp\u003eThis study has several strengths, including its randomized design, well-defined inclusion criteria, and focus on a homogenous surgical population, all of which enhance internal validity and minimize confounding\u0026mdash;common limitations in much of the existing ERASS literature. Nonetheless, several limitations warrant consideration. First, the relatively small sample size (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;42) limits the statistical power to detect small to moderate effects. This constraint resulted from the narrow inclusion criteria, intentionally designed to ensure population homogeneity. Given the limited sample size, the absence of statistical significance in several outcomes may reflect a Type II error. The observed trends\u0026mdash;such as lower discharge pain scores in the ERASS group\u0026mdash;may become significant in larger, adequately powered studies, suggesting a clinically relevant effect currently masked by sample constraints. Second, blinding was only partial, as the anesthesiology team was aware of group assignments, which may have introduced performance bias. Third, while key short-term clinical outcomes such as postoperative pain and LoS were evaluated, the study did not assess longer-term outcomes such as functional recovery, patient satisfaction, or cost-effectiveness as well as bone quality and BMI\u0026mdash;all of which are important metrics for comprehensively evaluating the clinical utility of ERASS protocols.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eWhile the ERASS protocol did not significantly reduce hospital length of stay in this RCT of single-level lumbar arthrodesis, it was associated with a trend toward improved postoperative pain control. Multivariate analysis suggests that discharge pain and PONV significantly influence short-term recovery outcomes. These findings highlight the complexity of evaluating ERAS protocols and underscore the need for larger, adequately powered studies focusing on procedure-specific ERAS components. In future research, integration of patient-reported outcomes and long-term follow-up may offer more comprehensive evaluation of ERASS efficacy.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eANOVA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eAnalysis of Variance\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eDHBP\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eDihydroergotamine, Betamethasone, and Paracetamol\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eERAS\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eEnhanced Recovery After Surgery\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eERASS\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eEnhanced Recovery After Spinal Surgery\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eIQR\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eInterquartile Range\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eLoS\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eLength of Stay\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eNRS\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eNumeric Rating Scale\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003ePONV\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003ePostoperative Nausea and Vomiting\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eRCT\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eRandomized Controlled Trial\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eSE\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eStandard Error\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eVIF\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eVariance Inflation Factor\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eWHO\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eWorld Health Organization\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eConceptualization, E.V.D.K, M.V, C.S and P.V; writing\u0026mdash;original draft preparation, A.K and J.P.; writing\u0026mdash;review and editing, A.K, J.P, D.T and E.V.D.K. All authors have read and agreed to the published version of the manuscript.\u0026rdquo;\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eAvailable upon request\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eJain V, Irrinki S, Khare S et al (2024) Implementation of modified enhanced recovery after surgery (ERAS) following surgery for abdominal trauma; Assessment of feasibility and outcomes: A randomized controlled trial (RCT). Am J Surg 238:115975\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLjungqvist O, Scott M, Fearon KC (2017) Enhanced Recovery After Surgery: A Review. JAMA Surg 152(3):292\u0026ndash;298\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSoffin EM, YaDeau JT (2016) Enhanced recovery after surgery for primary hip and knee arthroplasty: a review of the evidence. Br J Anaesth 117(suppl 3):iii62\u0026ndash;iii72\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDebono B, Wainwright TW, Wang MY, et al. Consensus statement for perioperative care in lumbar spinal fusion: Enhanced Recovery After Surgery (ERAS\u0026reg;) Society recommendations.\u003cem\u003eThe Spine Journal.\u003c/em\u003e 2021;21(5):729\u0026ndash;752\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eElsarrag M, Soldozy S, Patel P et al (2019) Enhanced recovery after spine surgery: a systematic review. Neurosurg Focus 46(4):E3\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSingh K, Bohl DD, Ahn J et al (2017) Multimodal Analgesia Versus Intravenous Patient-Controlled Analgesia for Minimally Invasive Transforaminal Lumbar Interbody Fusion Procedures. Spine (Phila Pa 1976) 42(15):1145\u0026ndash;1150\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSivaganesan A, Wick JB, Chotai S, Cherkesky C, Stephens BF, Devin CJ (2019) Perioperative Protocol for Elective Spine Surgery Is Associated With Reduced Length of Stay and Complications. J Am Acad Orthop Surg 27(5):183\u0026ndash;189\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChoi JU, Kee T-H, Lee D-H, Hwang CJ, Park S, Cho JH (2024) Enhanced Recovery After Surgery Protocols in One- or Two-Level Posterior Lumbar Fusion: Improving Postoperative Outcomes. J Clin Med 13(20). \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3390/jcm13206285\u003c/span\u003e\u003cspan address=\"10.3390/jcm13206285\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eNaftalovich R, Singal A, Iskander AJ (2022) Enhanced Recovery After Surgery (ERAS) protocols for spine surgery - review of literature. Anaesthesiol Intensive Ther 54(1):71\u0026ndash;79\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLiu B, Liu R, Wang L (2017) A meta-analysis of the preoperative use of gabapentinoids for the treatment of acute postoperative pain following spinal surgery. Med (Baltim) 96(37):e8031\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDuojun W, Hui Z, Zaijun L, Yuxiang G, Haihong C (2021) Enhanced recovery after surgery pathway reduces the length of hospital stay without additional complications in lumbar disc herniation treated by percutaneous endoscopic transforaminal discectomy. J Orthop Surg Res 16(1):461\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYao Y-C, Liou J-Y, Wang H-Y, Chou P-H, Lin H-H, Wang S-T Benefits of early recovery after surgery (ERAS) protocols on perioperative outcomes in patients undergoing elective lumbar spinal fusion: a prospective study. \u003cem\u003eThe Spine Journal\u003c/em\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHan D, Wang P, Kong C, Chen X, Lu S (2024) Enhanced recovery after surgery (ERAS) improves outcomes in elderly patients undergoing short-level lumbar fusion surgery: a retrospective study of 333 cases. Eur J Med Res 29(1):513\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSmith J, Probst S, Calandra C et al (2019) Enhanced recovery after surgery (ERAS) program for lumbar spine fusion. Perioperative Med 8(1):4\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eEaston RW, Lipphardt M, Papakonstantinou NS et al (2022) P67. ERAS protocol associated with improved measurable outcomes in patients undergoing lumbar spinal fusion. Spine J 22(9):S158\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"european-spine-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"esjo","sideBox":"Learn more about [European Spine Journal](http://link.springer.com/journal/586)","snPcode":"586","submissionUrl":"https://submission.springernature.com/new-submission/586/3","title":"European Spine Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Enhanced Recovery After Surgery (ERAS), Lumbar Athrodesis, Degenerative Spondylolisthesis, Length of stay, Postoperative pain","lastPublishedDoi":"10.21203/rs.3.rs-7786792/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7786792/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBACKGROUND AND OBJECTIVES: Enhanced Recovery After Surgery (ERAS) protocols aim to improve surgical outcomes, by mitigating postoperative stress through multimodal perioperative care. In spinal surgery, such protocols—termed Enhanced Recovery After Spine Surgery (ERASS)—may reduce pain, hospital length of stay (LoS), and opioid use. However, prior retrospective studies often suffer from heterogeneity in patient populations and surgical procedures, limiting interpretability. This trial was designed to evaluate the impact of an ERASS protocol on short-term clinical outcomes and LoS in patients undergoing elective single-level lumbar arthrodesis for degenerative spondylolisthesis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMETHODS: This single-center, randomized controlled trial included 42 patients allocated to ERASS (n=18) or standard care (n=24). The ERASS protocol included preoperative Gabapentin, early offering of dinner, intraoperative multimodal analgesia, and same-day physiotherapy. Primary outcome was LoS; secondary outcomes included pain at discharge, opioid use, complications, and readmissions. Data were analyzed using univariate statistical tests and multivariable regression models.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRESULTS: Median LoS was 3 days in both groups (p=0.685). Pain scores at discharge were lower in the ERASS group (mean 2.5 ± 1.5) versus control (3.1 ± 2.2), though not statistically significant (p=0.079). Multivariate analysis identified World Health Organization (WHO) pain medication level as a significant predictor of LoS (p=0.025), and postoperative nausea and vomiting (PONV) as a predictor of discharge pain (p=0.031). No significant differences were observed in complications or readmission rates.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCONCLUSION: While ERASS did not reduce LoS, it trended toward better pain outcomes. Discharge pain and PONV significantly impacted recovery, suggesting these as potential focal points for protocol refinement. Larger, procedure-specific trials with long-term follow-up are warranted.\u003c/p\u003e","manuscriptTitle":"Clinical impact of Enhanced Recovery After Spinal Surgery Protocols on One-Level Lumbar Arthrodesis: Results from a Single-Center Randomized Controlled Trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-27 17:23:23","doi":"10.21203/rs.3.rs-7786792/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-10-16T07:51:42+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-15T20:01:18+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-14T21:14:03+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"231103788246592189021208759378440656615","date":"2025-10-14T21:09:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"179185876143029493944186053058509590133","date":"2025-10-14T07:18:45+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-13T07:22:11+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-06T04:37:26+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-06T04:37:18+00:00","index":"","fulltext":""},{"type":"submitted","content":"European Spine Journal","date":"2025-10-05T21:02:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"european-spine-journal","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"esjo","sideBox":"Learn more about [European Spine Journal](http://link.springer.com/journal/586)","snPcode":"586","submissionUrl":"https://submission.springernature.com/new-submission/586/3","title":"European Spine Journal","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"5157b664-56b1-4383-a8f7-8ae3d06d43c7","owner":[],"postedDate":"October 27th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-29T16:04:41+00:00","versionOfRecord":{"articleIdentity":"rs-7786792","link":"https://doi.org/10.1007/s00586-025-09640-z","journal":{"identity":"european-spine-journal","isVorOnly":false,"title":"European Spine Journal"},"publishedOn":"2025-12-22 15:57:09","publishedOnDateReadable":"December 22nd, 2025"},"versionCreatedAt":"2025-10-27 17:23:23","video":"","vorDoi":"10.1007/s00586-025-09640-z","vorDoiUrl":"https://doi.org/10.1007/s00586-025-09640-z","workflowStages":[]},"version":"v1","identity":"rs-7786792","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7786792","identity":"rs-7786792","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}