The influence of delayed gastric emptying on quality of life after partial duodenopancreatectomy.

PURPOSE: Quality of life (QoL) is temporarily compromised after pancreatic surgery, but no evidence for a negative impact of postoperative complications on QoL has been provided thus far. Delayed gastric emptying (DGE) is one of the most common complications after pancreatic surgery and is associated with a high level of distress. Therefore, the aim of this study was to analyse the influence of DGE on QoL. METHODS: This single-centre retrospective study analysed QoL after partial duodenopancreatectomy (PD) via the European Organization for Research and Treatment of Cancer core questionnaire (QLQ-C30). The QoL of patients with and without postoperative DGE was compared. RESULTS: Between 2010 and 2022, 251 patients were included, 85 of whom developed DGE (34%). Within the first postoperative year, compared to patients without DGE, those with DGE had a significantly reduced QoL, by 9.0 points (95% CI: -13.0 to -5.1, p < 0.001). Specifically, physical and psychosocial functioning (p = 0.020) decreased significantly, and patients with DGE suffered significantly more from fatigue (p = 0.010) and appetite loss (p = 0.017) than patients without DGE. After the first postoperative year, there were no significant differences in QoL or symptom scores between patients with DGE and those without DGE. CONCLUSION: Patients who developed DGE reported a significantly reduced QoL and reduced physical and psychosocial functioning within the first year after partial pancreatoduodenectomy compared to patients without DGE.

Educational challenges and opportunities for the future generation of surgeons: a scoping review.

PURPOSE: Surgery offers exciting opportunities but comes with demanding challenges that require attention from both surgical program administrators and aspiring surgeons. The hashtag #NoTrainingTodayNoSurgeonsTomorrow on 𝕏 (previously Twitter) underscores the importance of ongoing training. Our scoping review identifies educational challenges and opportunities for the next generation of surgeons, analyzing existing studies and filling gaps in the literature. METHODS: Following the PRISMA guidelines, MEDLINE/PubMed was searched in February 2022, using the MeSH terms "surgeons/education," for articles in English or German on general, abdominal, thoracic, vascular, and hand surgery and traumatology targeting medical students, surgical residents, future surgeons, and fellows. RESULTS: The initial search yielded 1448 results. After a step-by-step evaluation process, 32 publications remained for complete review. Three main topics emerged: surgical innovations and training (n = 7), surgical culture and environment (n = 19), and mentoring (n = 6). The articles focusing on surgical innovations and training mainly described the incorporation of structured surgical training methods and program initiatives. Articles on surgical culture examined residents' burnout, well-being, and gender issues. Challenges faced by women, including implicit bias and sexual harassment, were highlighted. Regarding mentoring, mentees' needs, training challenges, and the qualities expected of both mentors and mentees were addressed. CONCLUSION: At a time of COVID-19-driven surgical innovations, the educational and working environment of the new generation of surgeons is changing. Robotic technology and other innovations require future surgeons to acquire additional technological and digital expertise. With regard to the cultural aspects of training, surgery needs to adapt curricula to meet the demands of the new generation of surgeons, but even more it has to transform its culture.

The PAncreatic Surgery Composite Endpoint PACE - Development and Validation of a Clinically Relevant Endpoint Requiring Lower Sample Sizes.

OBJECTIVE: To provide a composite endpoint in pancreatic surgery. SUMMARY BACKGROUND DATA: Single endpoints in prospective and randomized studies have become impractical due to their low frequency and the marginal benefit of new interventions. METHODS: Data from prospective studies were used to develop (n=1273) and validate (n=544) a composite endpoint based on postoperative pancreatic fistula, post-pancreatectomy hemorrhage as well as reoperation and reinterventions. All patients had pancreatectomies of different extents. The association of the developed PAncreatic surgery Composite Endpoint (PACE) with prolonged length of hospital stay (LOS) >75th percentile and mortality was assessed. A single-institution database was used for external validation (n = 2666). Sample size calculations were made for single outcomes and the composite endpoint. RESULTS: In the internal validation cohort, the PACE demonstrated an AUC of 78.0%, a sensitivity of 90.4% and a specificity of 67.6% in predicting a prolonged LOS. In the external cohort, the AUC was 76.9%, the sensitivity 73.8% and the specificity 80.1%. The 90-day mortality rate was significantly different for patients with a positive versus a negative PACE both in the development and internal validation cohort (5.1% vs 0.9%; P< 0.001), as well as in the external validation cohort (8.5% vs 1.2%, P< 0.001). The PACE enabled sample size reductions of up to 80.5% compared to single outcomes. CONCLUSION: The PACE performed well in predicting prolonged hospital stays and can be used as a standardized and clinically relevant endpoint for future prospective trials enabling lower sample sizes and therefore improved feasibility compared to single outcome parameters.

Framework for a living systematic review and meta-analysis for the surgical treatment of bladder cancer: introducing EVIglance to urology.

Background: Knowledge of current and ongoing studies is critical for identifying research gaps and enabling evidence-based decisions for individualized treatment. However, the increasing number of scientific publications poses challenges for healthcare providers and patients in all medical fields to stay updated with the latest evidence. To overcome these barriers, we aim to develop a living systematic review and open-access online evidence map of surgical therapy for bladder cancer (BC), including meta-analyses. Methods: Following the guidelines provided in the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement, a systematic literature search on uro-oncological therapy in BC will be performed across various literature databases. Within the scope of a meta-analysis and living systematic review, relevant randomized controlled trials will be identified. Data extraction and quantitative analysis will be conducted, along with a critical appraisal of the quality and risk of bias of each study. The available research evidence will be entered into an open-access framework (www.evidencemap.surgery) and will also be accessible via the EVIglance app. Regular semi-automatic updates will enable the implementation of a real-living review concept and facilitate resource-efficient screening. Discussion: A regularly updated evidence map provides professionals and patients with an open-access knowledge base on the current state of research, allowing for decision-making based on recent evidence. It will help identify an oversupply of evidence, thus avoiding redundant work. Furthermore, by identifying research gaps, new hypotheses can be formulated more precisely, enabling planning, determination of sample size, and definition of endpoints for future trials.

Career goals of surgeons in Switzerland.

PURPOSE: Recent studies from the United States and Germany have shown a general decline in the number of surgical residents, as trainees increasingly prioritize a positive work-life balance. The current study sought to evaluate the career goals of surgeons in Switzerland. METHODS: Members of the Swiss College of Surgeons, being surgical consultant or attending regardless of specialty, were surveyed online as to their purported career goals, future employment ideals, aspired leadership positions, and managerial training. RESULTS: A total of 269 questionnaires were analysed. Most participants (93%) were board- certified and 30% of participants were female. With regard to desired specialty, 50% of participants intended to pursue a career in visceral surgery followed by general surgery, traumatology, hand and plastic surgery, vascular surgery and thoracic surgery. Regardless of specialty, 53% of respondents strived for the position of senior physician, while 28% indicated a desire to become chief physician. In terms of work environment, most participants preferred to seek employment at a cantonal hospital, followed by a rural hospital, a university hospital, private practice or a non-clinical setting. About half of respondents favoured the option of part time employment of 80% or less and about a quartile intended to retire before 62 years of age. CONCLUSION: The current study found that surgeons in Switzerland remain highly motivated to pursue leadership positions in their respective fields. Going forward, the challenge will lie in reconciling the needs of the respective departments with the personal ambition, career opportunities, and desired work-life balance of young trainees.

Schistosomiasis (Schistosoma mansoni)-a rare cause of complex liver cysts.

In this paper, we describe the case of a 40-year-old patient with an expanding and symptomatic complex liver cyst. Despite comprehensive diagnostics, including labs, imaging and biopsy, a clear etiology could not be determined. As a result, a partial liver resection was performed. The histopathological examination revealed evidence of schistosomas. We postulate that the displacement of the portal fields created a pseudocyst and that the resultant ischemia was the root cause of the patient's discomfort. Postoperatively, the patient received an antihelmintic therapy with praziquantel with which she was able to fully recover.

Minimally invasive versus open pancreatic surgery: meta-analysis of randomized clinical trials.

BACKGROUND: Widespread implementation of the minimally invasive technique in pancreatic surgery has proven to be challenging. The aim of this study was to compare the perioperative outcomes of minimally invasive (laparoscopic and robotic) pancreatic surgery with open pancreatic surgery using data obtained from RCTs. METHODS: A literature search was done using Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Web of Science; all available RCTs comparing minimally invasive pancreatic surgery and open pancreatic surgery in adults requiring elective distal pancreatectomy or partial pancreatoduodenectomy were included. Outcomes were mortality rate, general and pancreatic surgery specific morbidity rate, and length of hospital stay. RESULTS: Six RCTs with 984 patients were included; 99.0 per cent (486) of minimally invasive procedures were performed laparoscopically and 1.0 per cent (five) robotically. In minimally invasive pancreatic surgery, length of hospital stay (-1.3 days, -2 to -0.5, P = 0.001) and intraoperative blood loss (-137 ml, -182 to -92, P < 0.001) were reduced. In the subgroup analysis, reduction in length of hospital stay was only present for minimally invasive distal pancreatectomy (-2 days, -2.3 to -1.7, P < 0.001). A minimally invasive approach showed reductions in surgical site infections (OR 0.4, 0.1 to 0.96, P = 0.040) and intraoperative blood loss (-131 ml, -173 to -89, P < 0.001) with a 75 min longer duration of surgery (42 to 108 min, P < 0.001) only in partial pancreatoduodenectomy. No significant differences were found with regards to mortality rate and postoperative complications. CONCLUSION: This meta-analysis presents level 1 evidence of reduced length of hospital stay and intraoperative blood loss in minimally invasive pancreatic surgery compared with open pancreatic surgery. Morbidity rate and mortality rate were comparable, but longer duration of surgery in minimally invasive partial pancreatoduodenectomy hints that this technique in partial pancreatoduodenectomy is technically more challenging than in distal pancreatectomy.

Perioperative Drug Treatment in Pancreatic Surgery-A Systematic Review and Meta-Analysis.

INTRODUCTION: Pancreatic resections for malignant or benign diseases are associated with major morbidity and changes in physiology. To reduce perioperative complications and enhance recovery, many types of perioperative medical management have been introduced. The aim of this study was to provide an evidence-based overview on the best perioperative drug treatment. METHODS: The electronic bibliographic databases Medline, Embase, CENTRAL, and Web of Science were systematically searched for randomized controlled trials (RCT) evaluating perioperative drug treatments in pancreatic surgery. The investigated drugs were somatostatin analogues, steroids, pancreatic enzyme replacement therapy (PERT), prokinetic therapy, antidiabetic drugs, and proton pump inhibitors (PPI). Targeted outcomes in each drug category were meta-analyzed. RESULTS: A total of 49 RCT were included. The analysis of somatostatin analogues showed a significantly lower incidence of postoperative pancreatic fistula (POPF) in the somatostatin group compared to the control group (OR 0.58, 95% CI: 0.45 to 0.74). The comparison of glucocorticoids versus placebo showed significantly less POPF in the glucocorticoid group (OR 0.22, 95% CI: 0.07 to 0.77). There was no significant difference in DGE when erythromycin was compared to placebo (OR 0.33, 95% CI: 0.08 to 1.30). The other investigated drug regimens could only be analyzed qualitatively. CONCLUSION: This systematic review provides a comprehensive overview on perioperative drug treatment in pancreatic surgery. Some often-prescribed perioperative drug treatments lack high quality evidence and further research is needed.

Middle Segment-Preserving Pancreatectomy to Avoid Pancreatic Insufficiency: Individual Patient Data Analysis of All Published Cases from 2003-2021.

Middle segment-preserving pancreatectomy (MPP) can treat multilocular diseases in the pancreatic head and tail while avoiding impairments caused by total pancreatectomy (TP). We conducted a systematic literature review of MPP cases and collected individual patient data (IPD). MPP patients (N = 29) were analyzed and compared to a group of TP patients (N = 14) in terms of clinical baseline characteristics, intraoperative course, and postoperative outcomes. We also conducted a limited survival analysis following MPP. Pancreatic functionality was better preserved following MPP than TP, as new-onset diabetes and exocrine insufficiency each occurred in 29% of MPP patients compared to near-ubiquitous prevalence among TP patients. Nevertheless, POPF Grade B occurred in 54% of MPP patients, a complication avoidable with TP. Longer pancreatic remnants were a prognostic indicator for shorter and less eventful hospital stays with fewer complications, whereas complications of endocrine functionality were associated with older patients. Long-term survival prospects after MPP appeared strong (median up to 110 months), but survival was lower in cases with recurring malignancies and metastases (median < 40 months). This study demonstrates MPP is a feasible treatment alternative to TP for selected cases because it can avoid pancreoprivic impairments, but at the risk of perioperative morbidity.

A Simple Classification of Pancreatic Duct Size and Texture Predicts Postoperative Pancreatic Fistula: A classification of the International Study Group of Pancreatic Surgery.

OBJECTIVE: The aim of this study was to develop a classification system for pancreas-associated risk factors in pancreatoduodenectomy (PD). SUMMARY BACKGROUND DATA: Postoperative pancreatic fistula (POPF) is the most relevant PD-associated complication. A simple standardized surgical reporting system based on pancreas-associated risk factors is lacking. METHODS: A systematic literature search was conducted to identify studies investigating clinically relevant (CR) POPF (CR-POPF) and pancreas-associated risk factors after PD. A meta-analysis of CR-POPF rate for texture of the pancreas (soft vs not-soft) and main pancreatic duct (MPD) diameter was performed using the Mantel-Haenszel method. Based on the results, the International Study Group of Pancreatic Surgery (ISGPS) proposes the following classification: A, not-soft (hard) texture and MPD >3 mm; B, not-soft (hard) texture and MPD ≤3 mm; C, soft texture and MPD >3 mm; D, soft texture and MPD ≤3 mm. The classification was evaluated in a multi-institutional, international cohort. RESULTS: Of the 2917 articles identified, 108 studies were included in the analyses. Soft pancreatic texture was significantly associated with the development of CR-POPF [odds ratio (OR) 4.24, 95% confidence interval (CI) 3.67-4.89, P < 0.01) following PD. Similarly, MPD diameter ≤3 mm significantly increased CR-POPF risk compared with >3 mm diameter MPDs (OR 3.66, 95% CI 2.62-5.12, P < 0.01). The proposed 4-stage system was confirmed in an independent cohort of 5533 patients with CR-POPF rates of 3.5%, 6.2%, 16.6%, and 23.2% for type A-D, respectively ( P < 0.001). CONCLUSION: For future pancreatic surgical outcomes studies, the ISGPS recommends reporting these risk factors according to the proposed classification system for better comparability of results.

Bariatric metabolic surgery eliminates body mass index as a risk factor for unemployment.

BACKGROUND: The effects of bariatric metabolic surgery (BMS) on health and comorbidities are well-known. Socioeconomic factors have been increasingly in focus in recent investigations. OBJECTIVE: The aim of this study was to analyze the effects of BMS on predictive variables for unemployment. SETTING: This study as performed in one reference center for BMS. Patients were treated between 2011 and 2017. METHODS: The study design was a retrospective cohort study. Inclusion criteria were Roux-en-Y gastric bypass surgery, follow-up of 60 months, and complete data on employment rate. Exclusion criteria were secondary BMS, secondary referral, loss of follow-up, or patients aged 60 years and above. Patients were stratified as employed independent of part-time work and as unemployed if the patient had no current employment at the time of the visit. Follow-up visits were performed after 6, 12, 24, 48, and 60 months. RESULTS: This study included 623 patients; prior to BMS, 239 (38.36%) patients were employed and 384 (61.64%) unemployed. Risk factors for baseline unemployment included increased body mass index (BMI) (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.01 to 1.05; P = .010) and increased American Society of Anesthesiology (ASA) score (OR, 3.55; 95% CI, 2.56 to 4.90; P < .001). Unemployment rate dropped to 32.4% after 24 months (P < .001) and increased to 62.8% after 60 months. The BMI continuously decreased. Following BMS, the unemployment rate was no longer associated with BMI (24 months: OR, 0.97; 95% CI, 0.95 to 1.01; P = .220; 60 months: 1.04; 95% CI, 0.97 to 1.11; P = .269). The initial ASA status remained associated with unemployment (OR, 2.20; 95% CI, 1.60 to 3.01; P < .001). CONCLUSION: BMI showed some association with the unemployment rate prior to BMI. The unemployment rate significantly decreased 24 months after BMS but increased to baseline values after 60 months. Following BMS, BMI was no longer associated with unemployment.

Multiple endocrine neoplasia type 4: a new member of the MEN family.

Objective: Multiple endocrine neoplasia type 4 (MEN4) is caused by a CDKN1B germline mutation first described in 2006. Its estimated prevalence is less than one per million. The aim of this study was to define the disease characteristics. Methods: A systematic review was performed according to the PRISMA 2020 criteria. A literature search from January 2006 to August 2022 was done using MEDLINE® and Web of ScienceTM. Results: Forty-eight symptomatic patients fulfilled the pre-defined eligibility criteria. Twenty-eight different CDKN1B variants, mostly missense (21/48, 44%) and frameshift mutations (17/48, 35%), were reported. The majority of patients were women (36/48, 75%). Men became symptomatic at a median age of 32.5 years (range 10-68, mean 33.7 ± 23), whereas the same event was recorded for women at a median age of 49.5 years (range 5-76, mean 44.8 ± 19.9) (P = 0.25). The most frequently affected endocrine organ was the parathyroid gland (36/48, 75%; uniglandular disease 31/36, 86%), followed by the pituitary gland (21/48, 44%; hormone-secreting 16/21, 76%), the endocrine pancreas (7/48, 15%), and the thyroid gland (4/48, 8%). Tumors of the adrenal glands and thymus were found in three and two patients, respectively. The presenting first endocrine pathology concerned the parathyroid (27/48, 56%) and the pituitary gland (11/48, 23%). There were one (27/48, 56%), two (13/48, 27%), three (3/48, 6%), or four (5/48, 10%) syn- or metachronously affected endocrine organs in a single patient, respectively. Conclusion: MEN4 is an extremely rare disease, which most frequently affects women around 50 years of age. Primary hyperparathyroidism as a uniglandular disease is the leading pathology.

Generating evidence for diagnosis and therapy of RarE LIVEr disease: the RELIVE Initiative for systematic reviews and meta-analyses.

BACKGROUND: Rare liver lesions and diseases have seldomly aroused major interest of researchers. For most guidelines, presumably similar clinical conditions are pooled without detailed investigations of singularities that they present. MAIN TEXT: A multidisciplinary project aiming to establish evidence-based therapies for rare liver diseases has been founded. A series of systematic reviews and meta-analyses will be the starting point for a structured development of guidelines for rare conditions of the liver affecting pediatric and adult populations. The novel approach will be focusing on case reports and small patient series with distinct rare liver diseases without pooling several presumably acceptably similar conditions. Thus, a vital resource of information will be utilized, which has been largely neglected hitherto. CONCLUSION: Highly specific recommendations based on highest available evidence will therefore be developed for specific conditions, advancing the individualized medicine approach for the afflicted patients.

The implementation of physicians assistant in a surgical ward improves continuity in daily clinical work and increases comprehensibility of nurses and physicians.

INTRODUCTION: Physician Assistant (PA) have been deployed to increase the capacity of a team, supporting continuity and medical cover. The goal of this study was to assess the implementation of PAs on continuity of surgical rounds, on the collaboration of nurses and physicians and on support of administrative work. METHODS: This cross-sectional survey was performed on nurses and physicians who work full-time at a surgical ward in a Swiss reference center. PAs were introduced in our institution in 2019. Participants answered a self-developed questionnaire 6 and 12 months after the implementation of PAs. Administrative work, teamwork, improvement of workflow, and training of physicians has been assessed. Participants answered questions on a 5-point Likert scale and were stratified according to profession (nurse, physician). RESULTS: Participants (n = 53) reported a positive effect on the regular conduct of rounds (2.9, SD 1.1 points after 6 weeks and 3.5, SD 1.1 points after 12 weeks, p = 0.05). A significant improvement of nurse-doctor collaboration has been reported (3.6, SD 1.0 and 4.2, SD 0.8, p = 0.05). Nurses (n = 28, 52.8%) reported the that PAs are integrated in the physicians team rather than the nurses team (4.0, SD 0.0 points and 4.4, SD 0.7 points, p = 0.266) and a significant beneficial effect on the surgical clinic (3.7, SD 1.0 points and 4.4, SD 0.8 points, p = 0.043). Improved overall management of surgical cases was reported by the physicians (n = 25, 47.2%) (4.8, SD 0.4 and 4.3, SD 0.6, p = 0.046). CONCLUSION: The implementation of PA has improved the collaboration of physicians and nurses substantially. Continuity of rounds has improved and the administrative workload for residents decreased substantially. Overall, the implementation of PA was reported to be beneficial for the surgical clinic.

Comparative effectiveness of medical treatment vs. metabolic surgery for histologically proven non-alcoholic steatohepatitis and fibrosis: a matched network meta-analysis.

Background: Non-alcoholic steatohepatitis (NASH) comprises a major healthcare problem affecting up to 30% of patients with obesity and the associated risk for cardiovascular and liver-related mortality. Several new drugs for NASH-treatment are currently investigated. No study thus far directly compared surgical and non-surgical therapies for NASH. This network meta-analysis compares for the first time the effectiveness of different therapies for NASH using a novel statistical approach. Methods: The study was conducted according to the PRISMA guidelines for network meta-analysis. PubMed, CENTRAL and Web of Science were searched without restriction of time or language using a validated search strategy. Studies investigating therapies for NASH in adults with liver biopsies at baseline and after at least 12 months were selected. Patients with liver cirrhosis were excluded. Risk of bias was assessed with ROB-2 and ROBINS-I-tools. A novel method for population-adjusted indirect comparison to include and compare single-arm trials was applied. Main outcomes were NASH-resolution and improvement of fibrosis. Results: Out of 7,913 studies, twelve randomized non-surgical studies and twelve non-randomized surgical trials were included. NASH-resolution after non-surgical intervention was 29% [95% confidence interval (CI): 23-40%] and 79% (95% CI: 72-88%) after surgery. The network meta-analysis showed that surgery had a higher chance of NASH-resolution than medication [odds ratio (OR) =2.68; 95% CI: 1.44-4.97] while drug treatment was superior to placebo (OR =2.24; 95% CI: 1.55-3.24). Surgery (OR =2.18; 95% CI: 1.34-3.56) and medication (OR =1.79; 95% CI: 1.39-2.31) were equally effective to treat fibrosis compared to placebo without difference between them. The results did not change when only new drugs specifically developed for the treatment of NASH were included. Conclusions: Metabolic surgery has a higher effectiveness for NASH-therapy than medical therapy while both were equally effective regarding improvement of fibrosis. Trials directly comparing surgery with medication must be urgently conducted. Patients with NASH should be informed about surgical treatment options.

Minimally invasivE versus open total GAstrectomy (MEGA): study protocol for a multicentre randomised controlled trial (DRKS00025765).

INTRODUCTION: The only curative treatment for most gastric cancer is radical gastrectomy with D2 lymphadenectomy (LAD). Minimally invasive total gastrectomy (MIG) aims to reduce postoperative morbidity, but its use has not yet been widely established in Western countries. Minimally invasivE versus open total GAstrectomy is the first Western multicentre randomised controlled trial (RCT) to compare postoperative morbidity following MIG vs open total gastrectomy (OG). METHODS AND ANALYSIS: This superiority multicentre RCT compares MIG (intervention) to OG (control) for oncological total gastrectomy with D2 or D2+LAD. Recruitment is expected to last for 2 years. Inclusion criteria comprise age between 18 and 84 years and planned total gastrectomy after initial diagnosis of gastric carcinoma. Exclusion criteria include Eastern Co-operative Oncology Group (ECOG) performance status >2, tumours requiring extended gastrectomy or less than total gastrectomy, previous abdominal surgery or extensive adhesions seriously complicating MIG, other active oncological disease, advanced stages (T4 or M1), emergency setting and pregnancy.The sample size was calculated at 80 participants per group. The primary endpoint is 30-day postoperative morbidity as measured by the Comprehensive Complications Index. Secondary endpoints include postoperative morbidity and mortality, adherence to a fast-track protocol and patient-reported quality of life (QoL) scores (QoR-15, EUROQOL EuroQol-5 Dimensions-5 Levels (EQ-5D), EORTC QLQ-C30, EORTC QLQ-STO22, activities of daily living and Body Image Scale). Oncological endpoints include rate of R0 resection, lymph node yield, disease-free survival and overall survival at 60-month follow-up. ETHICS AND DISSEMINATION: Ethical approval has been received by the independent Ethics Committee of the Medical Faculty, University of Heidelberg (S-816/2021) and will be received from each responsible ethics committee for each individual participating centre prior to recruitment. Results will be published open access. TRIAL REGISTRATION NUMBER: DRKS00025765.

Study protocol of REpeat versus SIngle ShoT Antibiotic prophylaxis in major Abdominal Surgery (RESISTAAS I): a prospective observational study of antibiotic prophylaxis practice for patients undergoing major abdominal surgery.

INTRODUCTION: Surgical site infections (SSIs) are among the most common complications after abdominal surgery and develop in approximately 20% of patients. These patients suffer a 12% increase in mortality, underlying the need for strategies reducing SSI. Perioperative antibiotic prophylaxis is paramount for SSI prevention in major abdominal surgery. Yet, intraoperative redosing criteria are subjective and whether patients benefit from it remains unclear. METHODS AND ANALYSIS: The REpeat versus SIngle ShoT Antibiotic prophylaxis in major Abdominal Surgery (RESISTAAS I) study is a single-centre, prospective, observational study investigating redosing of antibiotic prophylaxis in 300 patients undergoing major abdominal surgery. Adult patients scheduled for major abdominal surgery will be included. Current practice of redosing regarding number and time period will be recorded. Postoperative SSIs, nosocomial infections, clinically relevant infection-associated bacteria, postoperative antibiotic treatment, in addition to other clinical, pharmacological and economical outcomes will be evaluated. Differences between groups will be analysed with analysis of covariance. ETHICS AND DISSEMINATION: RESISTAAS I will be conducted in accordance with the Declaration of Helsinki and internal, national and international standards of GCP. The Medical Ethics Review Board of Heidelberg University has approved the study prior to initiation (S-404/2021). The study has been registered on 7 February 2022 at German Clinical Trials Register, with identifier DRKS00027892. We plan to disseminate the results of the study in a peer-reviewed journal. TRIAL REGISTRATION: German Clinical Trials Register (DRKS): DRKS00027892.