Revisional bariatric surgery for gastroesophageal reflux disease: characterizing patient and procedural factors and 30-day outcomes for a retrospective cohort of 4412 patients.

INTRODUCTION: Gastroesophageal reflux disease (GERD) is a well-established potential consequence of bariatric surgery and can require revisional surgery. Our understanding of the population requiring revision is limited. In this study, we aim to characterize patients requiring revisional surgery for GERD to understand their perioperative risks and identify strategies to improve their outcomes. METHODS: Using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) registry, a retrospective cohort of patients who required revisional surgery for GERD in 2020 was identified. Multivariable logistic regression modelling was used to assess correlations between baseline characteristics and morbidity. RESULTS: 4412 patients required revisional surgery for GERD, encompassing 24% of all conversion procedures. In most cases, patients underwent sleeve gastrectomy (SG) as their original surgery (n = 3535, 80.1%). The revisional surgery for most patients was a Roux-en-Y gastric bypass (RYGB) (n = 3722, 84.4%). Major complications occurred in 527 patients (11.9%) and 10 patients (0.23%) died within 30 days of revisional surgery. Major complications included anastomotic leak in 31 patients (0.70%) and gastrointestinal bleeding in 38 patients (0.86%). Multivariable analyses revealed that operative length, pre-operative antacid use, and RYGB were predictors of major complications. CONCLUSION: GERD is the second most common indication for revisional surgery in patients who have undergone bariatric surgery. Patients who underwent SG as their initial procedure were the primary group who required revisional surgery for GERD; most underwent revision via RYGB. Further inquiry is needed to tailor operative approaches and pre-operative optimization for revisional surgery patients.

Characteristics and outcomes for patients undergoing revisional bariatric surgery due to persistent obesity: a retrospective cohort study of 10,589 patients.

BACKGROUND: Revisional bariatric surgery in an option for patients who experience weight regain or inadequate weight loss after primary elective bariatric procedures. However, there is conflicting data on safety outcomes of revisional procedures. We aim to characterize patient demographics, procedure type, and safety outcomes for those undergoing revisional compared to initial bariatric interventions to guide management of these patients. METHODS: The 2020 Metabolic and Bariatric Accreditation and Quality Improvement Program (MBSAQIP) registry was analyzed, comparing primary elective to revisional bariatric procedures for inadequate weight loss. Bivariate analysis was performed to determine between group differences. Multivariable logistic regression determined factors associated with serious complications or mortality. RESULTS: We evaluated 158,424 patients, including 10,589 (6.7%) revisional procedures. Patients undergoing revisional procedures were more like to be female (85.5% revisional vs. 81.0% initial; p < 0.001), had lower body mass index (43.6 ± 7.8 kg/m2 revisional vs. 45.2 ± 7.8 kg/m2 initial; p < 0.001), and less metabolic comorbidities than patients undergoing primary bariatric surgery. The most common revisional procedures were Roux-en-Y gastric bypass (48.4%) and sleeve gastrectomy (32.5%). Revisional procedures had longer operative duration compared to primary procedures. Patients undergoing revisional procedures were more likely to experience readmission to hospital (4.8% revisional vs. 2.9% initial; p < 0.001) and require reoperation (2.4% revisional vs. 1.0% initial; p < 0.001) within 30 days of the procedure. Revisional procedures were independently associated with increased serious complications (OR 1.49, CI 1.36-1.64, p < 0.001) but were not a significant predictor of 30-day mortality (OR 0.74, CI 0.36-1.50, p = 0.409). CONCLUSIONS: In comparison to primary bariatric surgery, patients undergoing revisional procedures have less metabolic comorbidities. Revisional procedures have worse perioperative outcomes and are independently associated with serious complications. These data help to contextualize outcomes for patients undergoing revisional bariatric procedures and to inform decision making in these patients.

Substance abuse screening prior to bariatric surgery: an MBSAQIP cohort study evaluating frequency and factors associated with screening.

INTRODUCTION: Patients undergoing bariatric surgery experience substantial risk of pre- and postoperative substance use. Identifying patients at risk for substance use using validated screening tools remains crucial to risk mitigation and operative planning. We aimed to evaluate proportion of bariatric surgery patients undergoing specific substance abuse screening, factors associated with screening and the relationship between screening and postoperative complications. METHODS: The 2021 MBSAQIP database was analyzed. Bivariate analysis was performed to compare factors between groups who were screened for substance abuse versus non-screened, and to compare frequency of outcomes. Multivariate logistic regression analysis was performed to assess the independent effect of substance screening on serious complications and mortality, and to assess factors associated with substance abuse screening. RESULTS: A total of 210, 804 patients were included, with 133,313 (63.2%) undergoing screening and 77,491 (36.8%) who did not. Those who underwent screening were more likely to be white, non-smoker, and have more comorbidities. The frequency of complications was not significant (e.g., reintervention, reoperation, leak) or similar (readmission rates 3.3% vs. 3.5%) between screened and not screened groups. On multivariate analysis, lower substance abuse screening was not associated with 30-day death or 30-day serious complication. Factors that significantly affected likelihood of being screened for substance abuse included being black (aOR 0.87, p < 0.001) or other race (aOR 0.82, p < 0.001) compared to white, being a smoker (aOR 0.93, p < 0.001), having a conversion or revision procedure (aOR 0.78, p < 0.001; aOR 0.64, p < 0.001, respectively), having more comorbidities and undergoing Roux-en-y gastric bypass (aOR 1.13, p < 0.001). CONCLUSION: There remains significant inequities in substance abuse screening in bariatric surgery patients regarding demographic, clinical, and operative factors. These factors include race, smoking status, presence of preoperative comorbidities, and procedure type. Further awareness and initiatives highlighting the importance of identifying at risk patients is critical for ongoing outcome improvement.

Asian race is not associated with increased 30-day serious complications or mortality: a MBSAQIP analysis of 594,837 patients.

INTRODUCTION: With expansion of bariatric surgery indications to include Asian patients with diabetes and body mass index (BMI) ≥ 27.5, or BMI ≥ 32.5, it is important to characterize Asian patient population undergoing bariatric surgery and assess their postoperative outcomes. METHODS: This retrospective study analyzed the 2015-2019 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database. All patients undergoing Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy (LSG) who self-reported as Asian or White race were included. The primary outcomes were to characterize the Asian race population in North American and to identify if Asian race was associated with serious complications or mortality at 30 days. RESULTS: Overall, 594,837 patients met inclusion, with 4229 self-reporting Asian racial status. Patients of Asian race were younger (41.8 vs 45.5 years, p < 0.001) and had a lower BMI (42.8 vs 44.7 kg/m2 p < 0.001) than White patients. They were also more likely to have insulin dependent diabetes (10.9% vs 8.2%, p < 0.001), have received prior cardiac surgery (10.0% vs 1.2% p < 0.001), and suffer from renal insufficiency (1.0% vs 0.5%, p < 0.001). There were no significant differences between rates of RYGB (28.3% vs 28.9%, p = 0.4) and mean operative duration (87.7 vs 87.5 min, p = 0.7). Additionally, there were no differences in 30 day outcomes including leak (0.5% vs 0.5%, p = 0.625), bleeding (1.2% vs 1.0%, p = 0.1), serious complications (3.4% vs 3.5%, p = 0.6), or mortality (0.1% vs 0.1%, p = 0.7) and after confounder control, Asian race was not independently associated with serious complications (OR 1.0, CI 0.9-1.2, p = 0.7), or mortality (OR 1.1, CI 0.3-3.3, p = 0.1). CONCLUSIONS: Despite the increased metabolic burden of Asian patients, no differences in 30-day outcomes compared to White patients occurs. This data supports evidence suggesting these patients may safely undergo bariatric surgery independent of their increased metabolic burden.

A 5-year characterization of trends and outcomes in elderly patients undergoing elective bariatric surgery.

BACKGROUND: The North American population with severe obesity is aging and with that so will the number of elderly patients (≥ 65 years) meeting indications for metabolic surgery. Trends in bariatric delivery in this population are poorly characterized and outcomes remain conflicting, limiting potential uptake and delivery. METHODS: The MBSAQIP database was used to identify elderly patients (≥ 65 years) undergoing elective bariatric surgery from 2015 to 2019. Our objectives were to analyze their unique characteristics, surgical operative trends, and outcomes by comparing to a non-elderly cohort. Multivariable logistic regression identified independent predictors of serious complications and 30-day mortality. RESULTS: There was a total of 751,607 patients, 5.3% (n = 39,854) were elderly. Mean ages were 43 ± 11 years (non-elderly) versus 68 ± 3 years (elderly). Elderly patients were less likely to be female (70.7% elderly; 80.1% non-elderly) and had lower BMI (43.17 ± 6.64 kg/m2 elderly; 45.42 ± 7.87 kg/m2 non-elderly). They had higher American Society of Anesthesiologists classification, lower functional status, more insulin dependent diabetes, and hypertension, among other comorbidities. There were no clinically significant differences between the most frequently performed bariatric surgery. Sleeve gastrectomy remained the most common (73.7% non-elderly; 72.3% elderly); however, operative time was longer among the elderly. Functional status was most predictive for both serious complications (OR 1.72; CI 1.53-1.94) and mortality (OR 2.92; CI 1.98-4.31). Surgery among elderly patients was associated with poorer 30-day postoperative outcomes across all categories and was independently associated with serious complications (OR 1.23; CI 1.17-1.30, p < 0.001; AR 4.64%) and 30-day mortality (OR 2.49; CI 2.00-3.11, p < 0.001; AR 0.27%), after adjusting for comorbidities. CONCLUSIONS: After adjusting for comorbidities, functional status remains the most predictive factor for poor outcomes; however, elderly patients have increased 30-day odds of serious complications and 30-day mortality, suggesting a need to tailor our approach to these individuals that carry a unique operative risk.

Does ASA classification effectively risk stratify patients undergoing bariatric surgery: a MBSAQIP retrospective cohort of 138,612 of patients.

INTRODUCTION: It is important to appropriately risk stratify bariatric surgery patients, as these patients often have obesity-related comorbidities which can increase postoperative complication risk but also benefit the most from bariatric surgery. We aimed to evaluate the utility of risk stratification using ASA class for bariatric surgery patients and assessed predictive factors of postoperative complications. METHODS: The 2020 MBSAQIP database was analyzed, and an ASA-deemed high-risk cohort (class IV) and normal-risk (ASA class II and III) cohort were compared. Univariate analysis was performed to characterize differences between cohorts and to compare complication rates. Multivariate logistic regression analysis was performed to determine factors associated with increased odds of postoperative complications. RESULTS: We evaluated 138 612 patients with 5380 (3.9%) considered high-risk and 133 232 (96.1%) normal-risk. High-risk patients were more likely to be older (46.2 ± 12.0vs.43.4 ± 11.9, p < 0.001), male (30.9%vs.18.4%, p < 0.001), have higher BMI (51.4 ± 10.2vs.44.9 ± 7.4, p < 0.001), and have more comorbidities. High-risk patients were more likely to have increased 30-day serious complications (4.5%vs.2.8%, p < 0.001) and death (0.2%vs.0.1%, p = 0.001) but not anastomotic leak (0.2%vs.0.2%, p = 0.983). Multivariate models showed ASA class IV patients were at higher odds for any serious complication by 30 days (aOR 1.36, 95%CI 1.18-1.56, p < 0.001) but not for death (aOR 1.04, 95%CI 0.49-2.21, p = 0.921). The factor independently associated with the highest odds of complication in both models was functional status preoperatively (partially dependent aOR 2.06, 95%CI 1.56-2.72, p < 0.001; fully dependent aOR 3.19, 95%CI 1.10-9.28, p = 0.033 for any serious complication; partially dependent aOR 5.08, 95%CI 2.16-12.00, p < 0.001 for death). CONCLUSIONS: While elevated ASA class correlates with increased serious complications, pre-operative functional status appears to have a much greater contribution to odds of serious complications and mortality. These findings question the utility of using ASA to risk stratify patients peri-operatively and provides evidence for using a simpler and more practical functional status approach.

New persistent opioid use after bariatric surgery: a systematic review and pooled proportion meta-analysis.

INTRODUCTION: Increasing evidence suggests surgical patients are at risk for developing new, persistent opioid use (NPOU) following surgery. This risk may be heightened for patients undergoing bariatric surgery. Few studies have evaluated this important long-term outcome and little is known about the rate of NPOU, or factors associated with NPOU for bariatric surgery patients. METHODS AND PROCEDURE: We conducted a systematic review of MEDLINE, Embase, Scopus, Web of Science, and Cochrane databases in August 2021. Studies were reviewed and data extracted independently by two reviewers following MOOSE guidelines. Studies evaluating bariatric surgery patients reporting NPOU, defined as new opioid use > 90 days after surgery, were included. Abstracts, non-English, animal, n < 5, and pediatric studies were excluded. Primary outcome was NPOU prevalence, and secondary outcomes were patient and surgical factors associated with NPOU. Factors associated with NPOU are reported from findings of individual studies; meta-analysis could not be completed due to heterogeneity of reporting. RESULTS: We retrieved a total of 2113 studies with 8 meeting inclusion criteria. In studies reporting NPOU rates (n = 4 studies), pooled prevalence was 6.0% (95% CI 4.0-7.0%). Patient characteristics reported by studies to be associated with NPOU included prior substance use (tobacco, alcohol, other prescription analgesics), preoperative mental health disorder (anxiety, mood disorders, eating disorders), and public health insurance. Surgical factors associated with NPOU included severe post-operative complications and in-hospital opioid use (peri- or post operatively). CONCLUSIONS: NPOU is an uncommon but important complication following bariatric surgery, with patient factors including prior substance abuse, mental health disorders, and use of public health insurance placing patients at increased risk, and surgical factors being complications and peri-operative opioid use. Studies evaluating techniques to reduce NPOU in these high-risk populations are needed.

Endoscopic plication compared to laparoscopic fundoplication in the treatment of gastroesophageal reflux disease: a systematic review and meta-analysis.

INTRODUCTION: Endoscopic plication offers an alternative to surgical fundoplication for treatment of gastroesophageal reflux disease (GERD). This systematic review and meta-analysis evaluate outcomes following endoscopic plication compared to laparoscopic fundoplication. METHODS AND PROCEDURES: Systematic search of MEDLINE, Embase, Scopus, and Web of Science was conducted in September 2022. Study followed PRISMA guidelines. Studies comparing endoscopic plication to laparoscopic fundoplication with n > 5 were included. Primary outcome was PPI cessation, with secondary outcomes including complications, procedure duration, length of stay, change in lower esophageal sphincter (LES) tone, and DeMeester score. RESULTS: We reviewed 1544 studies, with five included comparing 105 (46.1%) patients receiving endoscopic plication (ENDO) to 123 (53.9%) undergoing laparoscopic fundoplication (LAP). Average patient age was 47.6 years, with those undergoing plication being younger (46.4 ENDO vs 48.5 LAP). BMI (26.6 kg/m2 ENDO vs 26.2 kg/m2 LAP), and proportion of females (42.9% ENDO vs 37.4% LAP) were similar. Patients undergoing laparoscopic procedures had worse baseline LES pressure (12.8 mmHg ENDO vs 9.0 mmHg LAP) and lower preoperative DeMeester scores (34.6 ENDO vs. 34.1 LAP). The primary outcome demonstrated that 89.2% of patients undergoing laparoscopic fundoplication discontinued PPI compared to 69.4% for those receiving plication. Meta-analysis revealed that plication had significantly reduced odds of PPI discontinuation (OR 0.27, studies = 3, 95% CI 0.12 to 0.64, P = 0.003, I2 = 0%). Secondary outcomes demonstrated that odds of complications (OR 1.46, studies = 4, 95% CI 0.34 to 6.32, P = 0.62, I2 = 0%), length of stay (MD - 1.37, studies = 3, 95% CI - 3.48 to 0.73, P = 0.20, I2 = 94%), and procedure durations were similar (MD 0.78, studies = 3, 95% CI - 39.70 to 41.26, P = 0.97, I2 = 98%). CONCLUSIONS: This is the first meta-analysis comparing endoscopic plication to laparoscopic fundoplication. Results demonstrate greater likelihood of PPI discontinuation with laparoscopic fundoplication with similar post-procedural risk.

Opioid prescribing practices following bariatric surgery: a systematic review and pooled proportion meta-analysis.

INTRODUCTION: A paucity of literature exists regarding current opioid prescribing and use following bariatric surgery. We aimed to characterize opioid prescribing practices and use following bariatric surgery to inform future studies and optimized prescribing practices. METHODS AND PROCEDURE: We performed a systematic review of Ovid MEDLINE, Ovid Embase, Scopus, Web of Science Core Collection, and Cochrane Library (via WILEY) on August 20, 2021. Two reviewers reviewed and extracted data independently. Studies evaluating adult patients undergoing bariatric surgery that reported opioid prescriptions at discharge were included. Abstracts, non-English studies, and those with n < 5 were excluded. Primary outcomes assessed the amount of morphine milligram equivalents (MMEs) prescribed at discharge. Secondary outcomes evaluated opioids used following discharge, proportion of patients with unused opioid, and if unused opioids were properly discarded. RESULTS: We evaluated 2113 studies, with 18 undergoing full-text review, and 5 meeting inclusion criteria. Overall, 847 patients were included, with 450 (53%) undergoing sleeve gastrectomy and 393 (46%) receiving Roux-en-Y gastric bypass. Most patients were female (n = 484/589, 82.2%), and the average age and BMI were 44.6 (± 11.8) years and 48.1 kg/m2 (± 8.4 kg/m2), respectively. On average, 348.4 MMEs were prescribed to patients undergoing bariatric surgery. Patients used only 84.7 MMEs, with 87.0% (95% CI 66.0-99.0%) having unused opioid, and 41/120 (34.2%) retaining these excess opioids. CONCLUSION: Nearly 90% of all bariatric patients evaluated in our systematic review are prescribed excessive opioids at discharge. Further work characterizing current opioid prescribing practices and use may help guide development of standardized post-bariatric surgery prescription guidelines.

Management of choledocholithiasis after Roux-en-Y gastric bypass: a systematic review and pooled proportion meta-analysis.

BACKGROUND: Several therapeutic modalities have been proposed for the management of choledocholithiasis (CDL) following Roux-en-Y gastric bypass (RYGB), yet debate exists regarding the optimal management. The purpose of our study was to review the current literature to compare the efficacy of various techniques in the management of CDL post-RYGB. METHODS: A comprehensive search of multiple databases was conducted. Studies reporting on the management of CDL in patients post-RYGB and including at least 5 patients were eligible for inclusion. The primary outcome was successful stone clearance. Secondary outcomes included procedure duration, length of hospital stay, and adverse events. RESULTS: Of 3259 identified studies, 53 studies involving 857 patients were included in the final analysis. The mean age was 54.4 years (SD 7.05), 78.8% were female (SD 13.6%), and the average BMI was 30.8 kg/m2 (SD 6.85). Procedures described included laparoscopy-assisted ERCP (LAERCP), balloon-assisted enteroscopy (BAE), ultrasound-directed transgastric ERCP (EDGE), laparoscopic common bile duct exploration (LCBDE), EUS-guided intra-hepatic puncture with antegrade clearance (EGHAC), percutaneous trans-hepatic biliary drainage (PTHBD), and rendezvous guidewire-associated (RGA) ERCP. High rates of successful stone clearance were observed with LAERCP (1.00; 95% CI 0.99-1.00; p = 0.47), EDGE (0.97; 95% CI 0.9-1.00; p = 0.54), IGS ERCP (1.00; 95% CI 0.87-1.00), PTHBD (1.0; 95% CI 0.96-1.00), and LCBDE (0.99; 95% CI 0.93-1.00, p < 0.001). Lower rates of stone clearance were observed with BAE (61.5%; 95%CI 44.3-76.3, p = 0.188) and EGHAC (74.0%; 95% CI 42.9-91.5, p = 0.124). Relative to EDGE, LAERCP had a longer procedure duration (133.1 vs. 67.4 min) but lower complication rates (12.8% vs. 24.3%). CONCLUSION: LAERCP and EDGE had high rates of success in the management of CDL post-RYGB. LAERCP had fewer complications but was associated with longer procedure times. BAE had lower success rates than both LAERCP and EDGE.

Characterization of Near-Infrared Imaging and Indocyanine-Green Use Amongst General Surgeons: A Survey of 263 General Surgeons.

BACKGROUND: Near-infrared fluorescence imaging (NIRFI) is an increasingly utilized imaging modality, however its use amongst general surgeons and its barriers to adoption have not yet been characterized. METHODS: This survey was sent to Canadian Association of General Surgeons and the Society of American Gastrointestinal and Endoscopic Surgeons members. Survey development occurred through consensus of NIRFI experienced surgeons. RESULTS: Survey completion rate for those opening the email was 16.0% (n = 263). Most respondents had used NIRFI (n = 161, 61.2%). Training, higher volumes, and bariatric, thoracic, or foregut subspecialty were associated with use (P < .001).Common reasons for NIRFI included anastomotic assessment (n = 117, 72.7%), cholangiography (n = 106, 65.8%), macroscopic angiography (n = 66, 41.0%), and bowel viability assessment (n = 101, 62.7%). Technical knowledge, training and poor evidence were cited as common barriers to NIRFI adoption. CONCLUSIONS: NIRFI use is common with high case volume, bariatric, foregut, and thoracic surgery practices associated with adoption. Barriers to use appear to be lack of awareness, low confidence in current evidence, and inadequate training. High quality randomized studies evaluating NIRFI are needed to improve confidence in current evidence; if deemed beneficial, training will be imperative for NIRFI adoption.

Surgical management of hiatal hernia vs medical therapy to treat bleeding Cameron lesions: a systematic review and meta-analysis.

INTRODUCTION: Cameron lesions (CL) are an under-recognized cause of gastrointestinal bleeding. Diagnosis is often impaired by technical difficulty, and once diagnosed, management remains unclear. Typically, patients are medically managed with proton pump inhibitors (PPI). Small studies have demonstrated improved therapeutic success with surgical management, hypothesizing that reversing mechanical gastric trauma and ischemia allows CL healing. This systematic review and meta-analysis aim to compare therapeutic success of surgical versus medical management of Cameron lesions (CL). METHODS AND PROCEDURES: A comprehensive search and systematic review selected manuscripts using the following inclusion criteria: (1) Endoscopically diagnosed CL (2) Treated surgically (3) Follow-up for resolution of anemia or CL (4) n ≥ 5 (5) Excluding non-English, animal, and studies with patients < 18 years old Meta-analysis was performed to compare resolution of CLs with medical and surgical therapy. RESULTS: Systematic search retrieved 1664 studies, of these, 14 were included (randomized controlled trial = 1; prospective = 2; retrospective = 11). Patients had a mean age of 61.2 years (range 24-91) and were more often female (59.3%). Follow-up was between 3 and 120 months, and 82.9% of patients had hernias > 5 cm. Surgical management was associated with therapeutic success (OR 5.20, 1.83-14.77, I2 = 42%, p < 0.001) with 92% having resolution, compared to 67.2% for those treated with PPI. Surgical complications occurred in 42/109 (38.5%) of patients (48.1% for Open Hill Repair, 15.4% for laparoscopic fundoplication). 40.0% of patients underwent a laparoscopic Nissen or Collis fundoplication, 21.7% underwent open modified Hill repair, and 38.3% had unspecified operations. Hemoglobin improved from 8.85 g/dL pre-operatively to 13.60 g/dL post-operatively. In six studies, surgical patients previously failed medical management. CONCLUSIONS: This is the first systematic review comparing surgical and medical treatment of CL. Surgical management significantly improved therapeutic success. Our study supports therapeutic benefit of surgery in these patients.

Higher Edmonton Obesity Staging System scores are independently associated with postoperative complications and mortality following bariatric surgery: an analysis of the MBSAQIP.

INTRODUCTION: Bariatric surgery is an evidence-based approach for sustained weight loss in patients with severe obesity. The most common procedures in North America are the laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB). The Edmonton Obesity Staging System (EOSS) is a tool that assigns patients a score of 0 to 4 according to their obesity-related comorbidities and functional status. Previous research demonstrates that increasing EOSS score is associated with overall non-operative mortality risk. OBJECTIVE: We sought to assess the association of the EOSS with major 30-day postoperative complications following LSG or LRYGB. METHODS: Primary LSG or LRYGB patients were identified from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry. Patients were assigned EOSS scores according to their comorbidities and functional limitations extracted from the database. Multivariable logistic regression analysis was conducted to evaluate the relationship between EOSS score, age, sex, BMI, type of procedure, or operative time with 30-day major complications. RESULTS: From 2015 to 2017, 430,238 patients (79.4% female) who underwent primary LSG or LRYGB were identified. The relative frequencies of patients by EOSS score were: 0 and 1 (23.9%), 2 (62.8%), 3 (10.5%), and 4 (2.9%). Mean preoperative BMI was 45.4 (SD 7.9) kg/m2 and mean age was 44.6 (SD 12.0) years. The overall 30-day major complication rate was 3.5%. EOSS 2, 3, and 4 were significantly associated with major complications. The strongest associations with major complications were EOSS 4 (OR 2.30; 95% CI 2.11-2.51, p < 0.001) and LRYGB versus LSG (OR 2.03; 95% CI 1.97-2.11, p < 0.001). EOSS 3 and 4 were most strongly associated with death. CONCLUSION: Higher EOSS scores are independently associated with 30-day major postoperative complications and mortality. The EOSS provides utility in staging patients and identifying those at greater risk of postoperative complications.

Intraoperative fluorescence imaging with indocyanine green in hepatic resection for malignancy: a systematic review and meta-analysis of diagnostic test accuracy studies.

BACKGROUND: Fluorescence imaging during hepatic resection has the potential to identify additional malignant tumors, increasing the chance for complete tumor resection. Indocyanine green (ICG) is an FDA approved, fluorescent dye used in a variety of surgical procedures. The objective of this study was to define the sensitivity of intraoperative ICG fluorescent imaging in the detection of hepatic malignancy in adult patients during hepatic resection, which was accomplished by performing a systematic review and meta-analysis. METHODS: The databases Medline, EMBASE, Scopus and Web of Science were assessed in September 2018. Article inclusion criteria was (1) Liver resection for malignancy (2) ICG injected pre or intraoperatively (3) Use of infrared electronic endoscopy or near-infrared fluorescence imaging intraoperatively (4) Patient age ≥ 18 years (5) N > 5 patients (6) Human and English studies only. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) guidelines were used for quality assessment. Data synthesis was completed using Meta-Disc and MedCalc software. A DerSimonian-Laird random effects model was used for the meta-analysis. RESULTS: 21 studies and 841 patients were included in our systematic review. Seven studies and 319 patients were included in the meta-analysis. The pooled sensitivity of intraoperative ICG fluorescence was 0.75 (0.71-0.79). Sensitivity for superficial tumors ranged from 0.96 to 1.00. Heterogeneity (I2) was calculated at 65.1%. ICG-related fluorescence imaging detected new malignant tumors not detected by conventional means in 42 of 362 patients across 13 studies. CONCLUSION: The sensitivity of intraoperative ICG-related imaging for superficial tumors is high; however, overall sensitivity is low, at 0.75, suggesting that it would have to be used in combination with current identification methods such as intraoperative ultrasound. Our study also found that intraoperative ICG fluorescence imaging was able to detect additional malignant hepatic tumors in 11.6% of patients.

Predicting surgical site infections following laparoscopic bariatric surgery: development of the BariWound tool using the MBSAQIP database.

BACKGROUND: Although bariatric surgery is a safe procedure for severe obesity, incisional surgical site infections (SSI) remain a significant cause of morbidity. Bariatric surgery patients are at high risk due to obesity and diabetes. The objective of this study was to develop a predictive tool for incisional SSI within 30 days of bariatric surgery. METHODS: Data were retrieved from the 2015 and 2016 MBSAQIP databases. This study included patients who underwent primary laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG). The primary outcome of interest was incisional SSI occurring within 30 days. Surgeries performed in 2015 were used in a derivation cohort and the predictive tool was validated against the 2016 cohort. A forward selection algorithm was used to build a logistic regression model predicting probability of SSI. RESULTS: A total of 274,187 patients were included with 71.7% being LSG and 28.3% LRYGB. 0.7% of patients had a SSI in which 71.0% had an incisional SSI, and 29.9% had an organ/space SSI. Of patients who had an incisional SSI, 88.7% were superficial, 10.9% were deep, and 0.4% were both. A prediction model to assess for risk of incisional SSI, BariWound, was derived and validated. BariWound consists of procedure type, chronic steroid or immunosuppressant use, gastroesophageal reflux disease, obstructive sleep apnea, sex, type 2 diabetes, hypertension, operative time, and body mass index. It stratifies individuals into very high (> 10%), high (5-10%), medium (1-5%), and low risk (< 1%) groups. This model accurately predicted events in the validation cohort with an area under the receiver operating characteristic curve of 0.73. CONCLUSIONS: BariWound accurately predicted the risk of 30-day incisional SSI in individuals undergoing bariatric surgery. Stratifying low- and high-risk groups allows for customized SSI prophylactic measures for patients in various risk categories and potentially enables future research targeted at high-risk patients.

Higher Edmonton Obesity Staging System scores are associated with complications following laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: The Edmonton Obesity Staging System (EOSS) is a staging system describing comorbidities and functional limitations associated with obesity, thus facilitating the prioritization of patients for bariatric surgery. Our objective was to elucidate any associations of EOSS scores with major complications after laparoscopic Roux-en-Y gastric bypass (LRYGB). METHODS: A retrospective chart review examined patients who received primary LRYGB from 2009 to 2015 at a single center. Collected data included patient comorbidities, preoperative EOSS stage, body mass index (BMI), age, percent excess weight loss, and 1-year major complications. Major complications were defined by a Clavien-Dindo classification ≥ IIIa. RESULTS: 378 patients (81.7% female) receiving primary LRYGB were reviewed with the following EOSS stages: 0 (3.7%), 1 (10.8%), 2 (78.6%), 3 (6.9%), and 4 (0.0%). The mean preoperative BMI was 45.9 (SD 6.3) kg/m2. The overall major complication rate was 9.3%. Major complication rates for EOSS stages 0, 1, 2, and 3 were 7.1%, 4.9%, 8.8%, and 23.1%, respectively. Follow-up rates at 12 months were 76.6% with a mean overall follow-up of 10.9 (2.1) months. Multivariable analysis showed that patients undergoing LRYGB with an EOSS of 3 were more likely to experience major complications (OR 2.94; CI 1.04 to 8.35, p = 0.043). CONCLUSION: Our findings suggest that undergoing LRYGB with EOSS stage 3 has increased odds of major complications. As such, the EOSS demonstrates utility in identifying bariatric surgery candidates at risk of major postoperative morbidity. Further studies are required to assess the applicability of the EOSS for patients undergoing other forms of bariatric surgery.

Design of freeforms to uniformly illuminate polygonal targets from extended sources via edge ray mapping.

In this article, we consider the design of a compact freeform optical surface that uniformly irradiates an arbitrary convex polygonal region from an extended light source, while controlling spill. This problem has attracted a large body of literature that has primarily covered highly symmetric special cases or cases where the solution is approximated by a zero-étendue design based on a point source. Practical versions of this illumination design problem will likely feature large asymmetric light-emitting diodes, compact lenses, and irregular targets on angled projection surfaces. For these settings, we develop a solution method based on an edge ray mapping that routes maximally off-axis rays from the edges of the source through the edge of the optic to the edges of the target polygon. This determines the sag and normals along the boundary of the freeform surface. A "spill-free" surface is then interpolated from the boundary information and optimized to uniformize the irradiance, while preserving the polygonal boundary. Highly uniform irradiances (relative standard deviation <.01) can be attained with good control of spill, even when the exit surface is less than three source diameters from the embedded source.

The Edmonton Obesity Staging System Predicts Mode of Delivery After Labour Induction.

OBJECTIVE: This study sought to evaluate the use of the Edmonton Obesity Staging System (EOSS) in predicting cesarean delivery among term, nulliparous, singleton pregnancies in women with overweight or obesity who are undergoing an induction of labour. METHODS: A prospective cohort study was performed in Edmonton, Alberta. Women undergoing an induction of labour at term were recruited to either a sample cohort, including women with a body mass index of ≥25 kg/m2 at first antenatal visit, or a control cohort with a body mass index of 18.5 to 24.9 kg/m2. Participating women provided a self-reported health history and consented to review of their medical records allowing allocation into EOSS categories. The primary outcome was the rate of cesarean delivery based on EOSS category. Secondary outcomes consisted of a summary score of adverse maternal, delivery, and neonatal events (Canadian Task Force Classification II-2). RESULTS: Overall, 345 women were recruited, with a participation rate of 93.7%. The sample cohort consisted of 276 women with overweight or obesity, whereas the control cohort included 69 normal-weight women. The overall rate of cesarean delivery was 30.4% for the control cohort and 35.8%, 29.9%, 43.2%, and 90.5% for women assigned an EOSS category 0, 1, 2, and 3, respectively (P < 0.001). A summary score was not indicative of overall rate of adverse maternal, delivery, and neonatal events (P = 0.22). CONCLUSION: The EOSS may help predict the chance of cesarean delivery in a high-risk group of nulliparous women with overweight or obesity who are undergoing an induction of labour at term.

Factors that predict 30-day readmission after bariatric surgery: experience of a publicly funded Canadian centre.

Background: Hospital readmissions after bariatric surgery can significantly increase health care costs. Rates of readmission after bariatric surgery have ranged from 0.6% to 11.3%, but the rate of complications and the factors that predict readmission have not been well characterized in Canada. The objective of this study was to characterize readmission rates and the factors that predict 30-day readmission in a Canadian centre. Methods: A retrospective study was performed on all patients who underwent bariatric surgery between 2010 and 2015 in a single Canadian centre. Procedures included laparoscopic Roux-en-Y gastric bypass (LRYGB), laparoscopic sleeve gastrectomy (LSG) and laparoscopic adjustable gastric banding (LAGB). Prospectively collected data were extracted from an administrative database. Multivariable logistic regression analysis was performed to determine which factors predict 30-day readmission. Results: A total of 1468 patients had bariatric surgery (51.0% LRYGB, 40.5% LSG, 8.6% LAGB) during the 6-year study period, with an overall 30-day readmission rate of 7.5%. LRYGB was associated with a higher readmission rate (11.4%) than LSG (3.7%) or LAGB (1.6%). Common reasons for readmission were infection (24.8%), pain (17.4%) and nausea or vomiting (10.1%). Multivariable analysis identified 3 factors that independently predicted readmission: length of stay greater than 4 days (odds ratio [OR] 2.18, 95% confidence interval [CI] 1.03-4.63, p = 0.042), LRYGB (OR 5.21, 95% CI 1.19-22.73, p = 0.028) and acute renal failure (OR 14.10, 95% CI 1.07-186.29, p = 0.045). Conclusion: Readmissions after bariatric surgery were most commonly caused by potentially preventable factors, such as pain, nausea or vomiting. Strategies to identify and address factors associated with readmission may reduce readmissions and health care costs after bariatric surgery in a publicly funded health care system.

Contexte: Les réadmissions hospitalières après la chirurgie bariatrique peuvent accroître significativement le coût des soins de santé. Les taux de ces réadmissions ont varié de 0,6 % à 11,3 %, mais le taux de complications et les facteurs de prédiction des réadmissions n'ont pas été bien caractérisés au Canada. L'objectif de cette étude est de caractériser les taux de réadmissions et les facteurs qui permettent de prédire une réadmission à 30 jours dans un centre canadien. Méthodes: Nous avons étudié rétrospectivement tous les cas de chirurgie bariatrique effectués entre 2010 et 2015 dans un établissement canadien. Les interventions incluaient la dérivation gastrique Roux-en-Y laparoscopique (DGRYL), la gastrectomie en manchon laparoscopique (GML) et la gastroplastie laparoscopique avec anneau ajustable (GLAA). Les données recueillies de manière prospective ont été extraites d'une base de données administrative. Nous avons procédé à une analyse de régression logistique multivariée pour déterminer quels facteurs permettaient de prédire la réadmission à 30 jours. Résultats: En tout, 1468 patients ont subi une chirurgie bariatrique (51,0 % DGRYL, 40,5 % GML et 8,6 % GLAA) durant les 6 années de l'étude, avec un taux global de réadmission à 30 jours de 7,5 %. La DGRYL a été associée un taux de réadmission plus élevé (11,4 %) que la GML (3,7 %) ou la GLAA (1,6 %). Les raisons de réadmission les plus fréquentes ont été infection (24,8 %), douleur (17,4 %) et nausées ou vomissements (10,1 %). L'analyse multivariée a permis de dégager 3 facteurs indépendants de réadmission, soit séjour de plus de 4 jours (rapport des cotes [RR] 2,18, intervalle de confiance [IC] de 95 % 1,03­4,63, p = 0,042), DGRYL (RC 5,21, IC de 95 % 1,19­22,73, p = 0,028) et insuffisance rénale aiguë (RC 14,10, IC de 95 % 1,07­186,29, p = 0,045). Conclusion: Les réadmissions après la chirurgie bariatrique ont le plus souvent été dues à des facteurs évitables, tels que douleur, nausées et vomissements. Des stratégies visant à identifier et à corriger les facteurs de réadmission pourraient réduire ces dernières et le coût des soins de santé après la chirurgie bariatrique dans un système de santé public.

Idiopathic intracranial hypertension and bariatric surgery: a systematic review

Background: Idiopathic intracranial hypertension (IIH) is a rare condition typically affecting women with obesity who are of child-bearing age. Patients commonly present with headaches, visual disturbances, pulsatile tinnitus and papilledema. The association between IIH and obesity has been well established in the literature, suggesting that weight loss may contribute to improving IIH. For patients with severe obesity for whom conservative management is not successful, bariatric surgery is an effective modality for weight loss. We aimed to systematically review the literature to determine the efficacy of bariatric surgery in the treatment of IIH Methods: We conducted a comprehensive search of MEDLINE, Embase, Scopus, the Cochrane Library and Web of Science (limited to studies in humans published in English between January 1946 and July 2015). Results: Twelve primary studies (n = 39 patients) were included in the systematic review. All patients had a preoperative diagnosis of IIH. Preoperative body mass index (BMI) was 47.4 ± 3.6 kg/m2 ; BMI improved to 33.7 ± 2.1 kg/m2 and 33.9 ± 11.6 kg/m2 at 6 and 12 months postoperatively, respectively. Lumbar puncture opening pressures decreased from 34.4 ± 6.9 cmH2O to 14.0 ± 3.6 cmH2O after surgery. Common symptoms of IIH improved after bariatric surgery: headaches (100% preoperatively v. 10% postoperatively), visual complaints (62% v. 44%), tinnitus (56% v. 3%) and papilledema (62% v. 8%). Conclusion: Bariatric surgery appears to lead to considerable improvement in IIH. Idiopathic intracranial hypertension is not a well-publicized comorbidity of obesity, but its presence may be considered as an indication for bariatric surgery.

Contexte: L'hypertension intracrânienne (HTIC) idiopathique est une affection rare qui touche surtout les femmes atteintes d'obésité en âge de procréer. Les symptômes courants sont des maux de tête, des troubles de la vue, des acouphènes pulsatiles et un oedème papillaire. Le lien entre l'HTIC idiopathique et l'obésité est bien établi dans la littérature, ce qui suggère que la perte de poids pourrait améliorer le tableau clinique de l'HTIC. Pour les patients atteints d'obésité sévère pour lesquels le traitement conservateur ne fonctionne pas, la chirurgie bariatrique est un moyen efficace de perdre du poids. Cette revue systématique de la littérature vise à déterminer l'efficacité de la chirurgie bariatrique dans le traitement de l'HTIC idiopathique. Méthodes: Nous avons interrogé MEDLINE, Embase, Scopus, la Bibliothèque Cochrane et Web of Science (limites : études portant sur les humains publiées en anglais entre janvier 1946 et juillet 2015). Résultats: Douze études primaires (n = 39 patients) ont été incluses dans la revue systématique. Tous les patients avaient un diagnostic préopératoire d'HTIC idiopathique. L'indice de masse corporelle (IMC) préopératoire était de 47,4 ± 3,6 kg/m2 ; l'IMC est passé à 33,7 ± 2,1 kg/m2 6 mois après l'opération, puis à 33,9 ± 11,6 kg/m2 12 mois après l'opération. Les pressions d'ouverture des ponctions lombaires sont passées de 34,4 ± 6,9 cmH2O à 14,0 ± 3,6 cmH2O après l'opération. Les symptômes courants de l'HTIC idiopathique se sont améliorés après la chirurgie bariatrique : maux de tête (100% avant opération c. 10% après), troubles de la vue (62% c. 44%), acouphènes pulsatiles (56% c. 3%) et œdème papillaire (62% c. 8%). Conclusion: La chirurgie bariatrique semble améliorer considérablement les symptômes d'HTIC idiopathique. Cette affection n'est pas une comorbidité bien connue de l'obésité, mais sa présence peut être une indication pour la chirurgie bariatrique comme traitement.