PReoperative very low-Energy diets for obese PAtients undergoing non-bariatric surgery Randomized Evaluation (PREPARE): a protocol for a pilot randomized controlled trial.

BACKGROUND: Patients with obesity presenting in need of surgical intervention are at 2-to-sixfold higher risk of prolonged hospitalization, infectious morbidity, venous thromboembolism, and more. To mitigate some of these concerns, prescribed preoperative weight loss via very low-energy diets (VLEDs) has become a standard of care for patients with obesity undergoing bariatric surgery. While VLEDs have become standard prior to bariatric surgery, their application in other surgical settings remains limited. A large, definitive trial is required to resolve the uncertainty surrounding their use in these patients. Prior to a definitive trial to compare the efficacy of VLEDs in patients with obesity undergoing major non-bariatric surgery, we require a pilot trial. We argue a pilot trial will provide the following critical feasibility insights: (1) assessment of recruitment ability, (2) evaluation of adherence to VLED regimens, and (3) assessment of our ability follow patients completely. METHODS: The proposed trial will be a multi-center, surgeon, outcome assessor, and data-analyst blinded, parallel pilot randomized controlled trial (RCT). Patients older than 18 years of age with a body mass index (BMI) of greater than 30 kg/m2 undergoing major elective non-bariatric surgery will be eligible for inclusion. Consecutive patients will be allocated 1:1 according to a computer-generated randomization schedule. Randomization will be stratified by center and will employ randomly permutated blocks. All patients in the intervention group will receive standard patient counseling on weight loss and an active VLED protocol. The preoperative VLED protocol will utilize commercially available weight loss products for three weeks preoperatively. The primary outcomes (randomization percentage, recruitment rate, intervention adherence, follow-up completion, network development) will assess feasibility. Descriptive statistics will be used to characterize the study sample. DISCUSSION: The PREPARE pilot RCT will aim to provide feasibility and safety data that will allow for the successful completion of the definitive PREPARE trial that has the potential to provide practice changing data pertaining to the regular use of VLEDs as a means of pre-habilitation for patients with obesity undergoing major non-bariatric surgery. TRIAL REGISTRATION: This study was registered on ClinicalTrials.gov (reference #NCT05918471) on June 23, 2023.

Outcomes of bariatric surgery in elderly patients: a registry-based cohort study with 3-year follow-up.

BACKGROUND: Elderly patients undergo bariatric surgery less frequently than younger patients. Short- and medium-term outcomes after bariatric surgery in the elderly population remain largely unknown. The objective of the present retrospective, registry-based cohort study was to compare short- and medium-term outcomes between patients <65 and ≥65 years undergoing bariatric surgery, hypothesizing similar outcomes between groups. METHODS: In this retrospective, registry-based cohort study, the Ontario Bariatric Registry was used to compare data of patients <65 and ≥65 years who underwent Roux-en-Y gastric bypass and sleeve gastrectomy between January 2010 and August 2019 in all accredited bariatric centers of excellence in Ontario, Canada. Primary outcomes were overall postoperative complications. Secondary outcomes included early (<30 days) complications, readmissions, reoperations, mortality, weight loss and comorbidities improvement at 1 and 3 year after surgery. RESULTS: Data of 22,981 patients <65 and 532 patients ≥65 years were analyzed. Overall postoperative complications were similar between patients <65 and ≥65 years (3388/22,981 [14.7%] vs. 73/532 [13.7%], p = 0.537). Early (<30 days) postoperative complications, readmissions, reoperations, and mortality rates were also similar between groups. Both groups had significant weight loss and comorbidities improvement at 1- and 3-year follow-up. Patients <65 years had superior weight loss (+3.5%, 95% CI: 1.6-5.4, p < 0.001) and higher rates of remission for diabetes mellitus (63.8% vs. 39.3%, p < 0.001), hypertension (37.9% vs. 14.5%, p < 0.001), dyslipidemia (28.2% vs. 9.5%, p < 0.001) and gastroesophageal reflux (65.1% vs. 24.0 %, p < 0.001) compared to patients ≥65 years at 3 year. CONCLUSIONS: Patients <65 and ≥65 years had similar perioperative morbidity and mortality after bariatric surgery. Even though patients <65 years had overall better medium-term outcomes, bariatric surgery is safe and yields significant weight loss and comorbidities improvement in patients ≥65 years.

Posterior mesorectal thickness as a predictor of increased operative time in rectal cancer surgery: a retrospective cohort study.

BACKGROUND: In rectal cancer surgery, larger mesorectal fat area has been shown to correlate with increased intraoperative difficulty. Prior studies were mostly in Asian populations with average body mass indices (BMIs) less than 25 kg/m2. This study aimed to define the relationship between radiological variables on pelvic magnetic resonance imaging (MRI) and intraoperative difficulty in a North American population. METHODS: This is a single-center retrospective cohort study analyzing all patients who underwent low anterior resection (LAR) or transanal total mesorectal excision (TaTME) for stage I-III rectal adenocarcinoma from January 2015 until December 2019. Eleven pelvic magnetic resonance imaging measures were defined a priori according to previous literature and measured in each of the included patients. Operative time in minutes and intraoperative blood loss in milliliters were utilized as the primary indicators of intraoperative difficulty. RESULTS: Eighty-three patients (39.8% female, mean age: 62.4 ± 11.6 years) met inclusion criteria. The mean BMI of included patients was 29.4 ± 6.2 kg/m2. Mean operative times were 227.2 ± 65.1 min and 340.6 ± 78.7 min for LARs and TaTMEs, respectively. On multivariable analysis including patient, tumor, and MRI factors, increasing posterior mesorectal thickness was significantly associated with increased operative time (p = 0.04). Every 1 cm increase in posterior mesorectal thickness correlated with a 26 min and 6 s increase in operative time. None of the MRI measurements correlated strongly with BMI. CONCLUSION: As the number of obese rectal cancer patients continues to expand, strategies aimed at optimizing their surgical management are paramount. While increasing BMI is an important preoperative risk factor, the present study identifies posterior mesorectal thickness on MRI as a reliable and easily measurable parameter to help predict operative difficulty. Ultimately, this may in turn serve as an indicator of which patients would benefit most from pre-operative resources aimed at optimizing operative conditions and postoperative recovery.

Comparison of single- versus double-anastomosis duodenal switch: a single-center experience with 2-year follow-up.

BACKGROUND: Single-anastomosis duodenal switch (SADS) has emerged in recent years as an alternative to the standard double-anastomosis duodenal switch (DADS). The objective of this study was to compare short- and medium-term outcomes between SADS and DADS. METHODS: Data collected in the Ontario Bariatric Registry between 2010 and 2019 were used for this retrospective study to determine outcomes of patients undergoing primary laparoscopic SADS versus DADS at a Canadian tertiary hospital and bariatric center of excellence. The primary outcome was weight loss at 1 and 2 years after surgery. Short-term secondary outcomes included operative times, intra- and early postoperative complications, hospital length of stay (LOS), and 30-day readmissions. Medium-term secondary outcomes included late postoperative complications as well as nutritional deficiencies and persistent diarrhea at 1 and 2 years after surgery. Subgroup analyses were performed to compare patients undergoing one- and two-stage procedures. RESULTS: Data of 107 patients who underwent SADS (n = 25) or DADS (n = 82) were included in the study. Follow-up data were available for 59/107 (55.1%) patients at 1 year and 47/107 (43.9%) at 2 years after surgery. Patients in the SADS and DADS groups had similar %TBWL at 1 year (23.6 versus 26.2, P = 0.617) and 2 years (24.8 versus 30.2, P = 0.116) after surgery. Short- and medium-term outcomes were similar between groups. There was no difference between patients undergoing one- versus two-stage procedures. CONCLUSION: This study showed that patients undergoing SADS and DADS had similar weight loss at 1 and 2 years. Early and late postoperative morbidity, operative times, early readmissions, and LOS were also similar between groups. Further studies with longer follow-up are required to confirm these results.

Selective Opioid Antagonists Following Bowel Resection for Prevention of Postoperative Ileus: a Systematic Review and Meta-analysis.

BACKGROUND: Postoperative ileus (POI) remains a common complication following bowel resection. Selective opioid antagonists have been increasingly studied as prophylactic pharmaceutical aids to reduce rates of POI. The aim of this study was to evaluate the impact of selective opioid antagonists on return of bowel function following bowel resection. METHODS: MEDLINE, Embase, and CENTRAL were systematically searched. Articles were included if they compared the incidence of POI and/or length of stay (LOS) in patients receiving and not receiving selective opioid antagonists following elective bowel resection. A pairwise meta-analyses using inverse variance random effects was performed. RESULTS: From 636 citations, 30 studies with 45,051 patients receiving selective opioid antagonists (51.3% female, mean age: 60.9) and 55,071 patients not receiving selective opioid antagonists (51.2% female, mean age: 61.1) were included. Patients receiving selective opioid antagonists had a significantly lower rate of POI (10.1% vs. 13.8%, RR 0.68, 95%CI 0.63-0.75, p < 0.01). Selective opioid antagonists also significantly reduced LOS (MD - 1.08, 95%CI - 1.47 to - 0.69, p < 0.01), readmission (RR 0.94, 95%CI 0.89-0.99, p = 0.03), and 30-day morbidity (RR 0.85, 95%CI 0.79-0.90, p < 0.01). Improvements in LOS, readmission rate, and morbidity were not significant when analysis was limited to laparoscopic surgery. There was no significant difference in inpatient healthcare costs (SMD - 0.33, 95%CI - 0.71-0.04, p = 0.08). CONCLUSIONS: Rate of POI decreases with the use of selective opioid antagonists in patients undergoing bowel resection. Selective opioid antagonists also improve LOS, rates of readmission, and 30-day morbidity for patients undergoing open bowel resection. Addition of these medications to enhance recovery after surgery protocols should be considered.

Comparison of clinical and economic outcomes between robotic, laparoscopic, and open rectal cancer surgery: early experience at a tertiary care center.

BACKGROUND: Robotic surgery has gained popularity in surgical oncology. Rectal cancer surgery, known to be technically challenging, may benefit from robotics in achieving better mesorectal dissection and may contribute to improved perioperative outcomes. The objective of this study was to compare early experience in robotic surgery to conventional approaches with regard to clinicopathologic and economic parameters. METHODS: A retrospective review using a prospectively maintained database of rectal cancer surgeries performed at a tertiary cancer center from 2007 to 2013 was conducted. These resections included those performed via laparotomy, laparoscopy, and robotic-assisted operations. Perioperative demographic and tumor characteristics were collected, and short-term clinicopathologic outcomes were compared. Additionally, economic variables were evaluated for each patient's episode of care. RESULTS: Seventy-nine cases were identified. Twenty-six were completed via open approach, 27 laparoscopically, and 26 via robotic assistance. Demographic characteristics were similar between all groups including age, gender, BMI, and Charlson score. Comparison of intraoperative characteristics showed a lower rate of conversion to laparotomy (12 vs. 37%, p = 0.05), and lower estimated blood loss (mean 296 vs. 524 cc, p = 0.04), in the robotic group compared to laparoscopy or open resection. There was no significant difference in quality of total mesorectal excision and number of lymph nodes harvested between the three cohorts. Postoperative complication rate, mean length of stay, 30-day readmission, and 30-day mortality were comparable among the cohorts. Median cost per episode of care was lower in laparoscopic surgery ($11,493), compared to open ($12,558) and robotic approach ($18,273); p = 0.029. CONCLUSIONS: The findings demonstrate similar perioperative and short-term outcomes between robotic surgery and conventional approaches. Robotic assistance is associated with decreased intraoperative blood loss and fewer conversions, albeit at an increased overall cost. Given these benefits, and as data and experience mature, future study is needed to fully define the value of the robotic approach.