30-day morbidity and mortality of revisional bariatric surgery - An international multi-centre collaborative (BROAD) study.

INTRODUCTION: Revisional bariatric surgery (RBS) for insufficient weight loss/weight regain or metabolic relapse is increasing worldwide. There is currently no large multinational, prospective data on 30-day morbidity and mortality of RBS. In this study, we aimed to evaluate the 30-day morbidity and mortality of RBS at participating centres. METHODS: An international steering group was formed to oversee the study. The steering group members invited bariatric surgeons worldwide to participate in this study. Ethical approval was obtained at the lead centre. Data were collected prospectively on all consecutive RBS patients operated between 15th May 2021 to 31st December 2021. Revisions for complications were excluded. RESULTS: A total of 65 global centres submitted data on 750 patients. Sleeve gastrectomy (n = 369, 49.2 %) was the most common primary surgery for which revision was performed. Revisional procedures performed included Roux-en-Y gastric bypass (RYGB) in 41.1 % (n = 308) patients, One anastomosis gastric bypass (OAGB) in 19.3 % (n = 145), Sleeve Gastrectomy (SG) in 16.7 % (n = 125) and other procedures in 22.9 % (n = 172) patients. Indications for revision included weight regain in 615(81.8 %) patients, inadequate weight loss in 127(16.9 %), inadequate diabetes control in 47(6.3 %) and diabetes relapse in 27(3.6 %). 30-day complications were seen in 80(10.7 %) patients. Forty-nine (6.5 %) complications were Clavien Dindo grade 3 or higher. Two patients (0.3 %) died within 30 days of RBS. CONCLUSION: RBS for insufficient weight loss/weight regain or metabolic relapse is associated with 10.7 % morbidity and 0.3 % mortality. Sleeve gastrectomy is the most common primary procedure to undergo revisional bariatric surgery, while Roux-en-Y gastric bypass is the most commonly performed revision.

From Bands to Bypasses: Navigating Safety of Band Conversions to Roux-en-Y Gastric Bypass and Single Anastomosis Duodenoileostomy Versus Sleeve Gastrectomy.

INTRODUCTION: Revisional bariatric surgery is associated with higher perioperative complications over primary procedures. Adjustable gastric bands (AGB) continue to be the most frequently converted bariatric configuration. This study examines trends in current clinical indication and safety profile of the most frequently pursued AGB conversions. MATERIALS AND METHODS: MBSAQIP data from 2020 to 2022 was retrospectively analyzed in a cohort study examining 30-day postoperative outcomes after AGB conversion to sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), or single anastomosis duodenoileostomy (SADI). Descriptive statistics were used, including multivariable and 2:1 nearest neighbor matching analysis. RESULTS: This study included 19,335 AGB conversions, of which most were to SG (n = 11,736) followed by RYGB (n = 7442) and SADI (n = 157). While a majority were completed for weight loss, there were differences in distribution of primary indication for each conversion cohort, such as higher proportion of RYGB conversion for gastroesophageal reflux disease (18.7%) compared to SG (7.92%) and SADI (5.10%). Multivariable analysis demonstrates conversion to RYGB has significantly higher odds of 30-day major complications (OR 1.75, p < 0.001), reoperation (OR 2.08; p = 0.001), readmission (OR 1.69; p = 0.001), and emergency department visits (OR 1.50; p = 0.001) over SG. These risks and odds of reintervention (OR 1.75; p < 0.001) remained significantly higher after conversion to RYGB versus SG on matched analysis. None of these risks is significantly different between conversions to SADI versus SG in either multivariable or matched analysis. CONCLUSIONS: Compared to AGB conversion to SG, single-stage conversion to RYGB had increased odds of perioperative complications while risks of conversion to SADI were not significantly different.

Early Successful Experiences of Surgical Conversion of Endoscopic Gastric Plication to Roux-en-Y Gastric Bypass.

BACKGROUND: The primary obesity surgery endoluminal (POSE) procedure is an innovative incision-less endoscopic bariatric procedure that is increasingly used. However, variable weight loss response and recurrence post-endoscopic bariatric procedures have at times necessitated laparoscopic bariatric conversion. The safety and approach of conversion to laparoscopic sleeve gastrectomy (LSG) or Roux-en-Y gastric bypass (RYGB), however, have been an active point of discussion within revisional bariatric surgery. METHODS: This retrospective review of four consecutive patients is the largest description of medium-term postoperative outcomes and technical highlights of a laparoscopic conversion of POSE to RYGB. Chart review was completed to evaluate patients' post-POSE clinical course and perioperative outcomes after surgical conversion. RESULTS: Early data suggests varied weight loss trajectory with POSE and marked improvement in weight response after surgical conversion. Qualitative review reveals successful single-staged conversions contrary to previous smaller case series describing staged conversions involving endoscopic removal of plications followed by RYGB. Review additionally reveals key perioperative considerations for successful conversions to include intraoperative endoscopy, upper gastrointestinal fluoroscopic studies, and at times computed tomography. The latter study and laparoscopic view of the post-POSE stomach challenge the prior notion that distal POSE allows for easy revision to LSG. CONCLUSIONS: Our case series underscores the complex multifactorial nature of metabolic disease and the increasing importance of a conscientious approach to conversion bariatric surgery as the adoption of POSE and the bariatric patient population continues to grow.

Harnessing artificial intelligence in bariatric surgery: comparative analysis of ChatGPT-4, Bing, and Bard in generating clinician-level bariatric surgery recommendations.

BACKGROUND: The formulation of clinical recommendations pertaining to bariatric surgery is essential in guiding healthcare professionals. However, the extensive and continuously evolving body of literature in bariatric surgery presents considerable challenge for staying abreast of latest developments and efficient information acquisition. Artificial intelligence (AI) has the potential to streamline access to the salient points of clinical recommendations in bariatric surgery. OBJECTIVES: The study aims to appraise the quality and readability of AI-chat-generated answers to frequently asked clinical inquiries in the field of bariatric and metabolic surgery. SETTING: Remote. METHODS: Question prompts inputted into AI large language models (LLMs) and were created based on pre-existing clinical practice guidelines regarding bariatric and metabolic surgery. The prompts were queried into 3 LLMs: OpenAI ChatGPT-4, Microsoft Bing, and Google Bard. The responses from each LLM were entered into a spreadsheet for randomized and blinded duplicate review. Accredited bariatric surgeons in North America independently assessed appropriateness of each recommendation using a 5-point Likert scale. Scores of 4 and 5 were deemed appropriate, while scores of 1-3 indicated lack of appropriateness. A Flesch Reading Ease (FRE) score was calculated to assess the readability of responses generated by each LLMs. RESULTS: There was a significant difference between the 3 LLMs in their 5-point Likert scores, with mean values of 4.46 (SD .82), 3.89 (.80), and 3.11 (.72) for ChatGPT-4, Bard, and Bing (P < .001). There was a significant difference between the 3 LLMs in the proportion of appropriate answers, with ChatGPT-4 at 85.7%, Bard at 74.3%, and Bing at 25.7% (P < .001). The mean FRE scores for ChatGPT-4, Bard, and Bing, were 21.68 (SD 2.78), 42.89 (4.03), and 14.64 (5.09), respectively, with higher scores representing easier readability. CONCLUSIONS: LLM-based AI chat models can effectively generate appropriate responses to clinical questions related to bariatric surgery, though the performance of different models can vary greatly. Therefore, caution should be taken when interpreting clinical information provided by LLMs, and clinician oversight is necessary to ensure accuracy. Future investigation is warranted to explore how LLMs might enhance healthcare provision and clinical decision-making in bariatric surgery.

The SAGES MASTERS program bariatric surgery pathway selects 10 seminal publications on revisional bariatrics.

BACKGROUND: The Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Masters Program designated bariatric surgery as a clinical pathway. Among the tiers of the Masters Program, revisional bariatric surgery is the highest tier of "mastery" within the pathway. This article presents the top 10 seminal studies representing the current landscape of revisional bariatrics. METHODS: The literature was systematically searched and seminal articles designated by consensus agreement of the SAGES Metabolic and Bariatric Surgery committee using multiple criteria, including impact on the field, citation frequency, and expert opinion. Articles were reviewed by committee members and presented in summarized fashion. RESULTS: The top 10 papers are presented in grouped thematic categories covering the early evolution of revisional bariatrics, changing criteria for reoperative bariatric surgery, divergence of revision versus conversion bariatric surgery, and recent technologic innovations in revisional bariatric surgery. Each summary is presented with expert appraisal and commentary. CONCLUSION: These seminal papers represent a snapshot of the dynamic field of revisional bariatric surgery and emphasize the need to not only remain current with contemporary trends but also keep a patient-oriented perspective on patient and intervention selection for optimal success.

Safety of limb lengthening after Roux-en-Y gastric bypass: an analysis of the MBSAQIP database.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) effectively treats severe obesity, but some patients may require revisional surgery like limb lengthening (LL) for postoperative weight gain. OBJECTIVES: This study aims to compare 30-day serious complications and mortality rates between LL and primary RYGB, given limited safety data on LL. METHODS: Patients who underwent LL and RYGB were identified from the 2020 and 2021 MBSAQIP databases, the only years in which LL data were available. Baseline characteristics and 30-day rates of serious complications and mortality were analyzed. RESULTS: A total of 86,990 patients underwent RYGB and 455 underwent LL. Patients undergoing RYGB were younger (44.4 versus 49.8 yr, P < .001), had a higher body mass index (BMI) (45.5 versus 41.8 kg/m2, P < .001) and higher rates of comorbidities including diabetes (30.0 versus 13.6%, P < .001). RYGB and LL had similar operative duration (125.3 versus 123.2 min, P = .5). There were no statistical differences between cohorts for length of stay (LOS) (1.6 RYGB versus 1.6 LL d, P = .6). After LL, there were higher 30-day rates of reoperation (3.3 versus 1.9%, P = .03) and deep surgical site infections (1.3 versus .5%, P = .03) compared to RYGB. There were no differences in overall serious complications (5.1 LL versus 5.0% RYGB, P = 1.0) and mortality (.2 LL versus .1% RYGB, P = .5). Multivariable logistic regression adjustment found that previous venous thromboembolism was associated with serious complications after LL. CONCLUSIONS: When compared to primary RYGB, LL has a favorable safety profile with similar 30-day rates of serious complications and mortality.

Workplace absenteeism due to COVID-19 and influenza across Canada: A mathematical model.

The continual distress of COVID-19 cannot be overemphasized. The pandemic economic and social costs are alarming, with recent attributed economic loss amounting to billions of dollars globally. This economic loss is partly driven by workplace absenteeism due to the disease. Influenza is believed to be a culprit in reinforcing this phenomenon as it may exist in the population concurrently with COVID-19 during the influenza season. Furthermore, their joint infection may increase workplace absenteeism leading to additional economic loss. The objective of this project will aim to quantify the collective impact of COVID-19 and influenza on workplace absenteeism via a mathematical compartmental disease model incorporating population screening and vaccination. Our results indicate that appropriate PCR testing and vaccination of both COVID-19 and seasonal influenza may significantly alleviate workplace absenteeism. However, with COVID-19 PCR testing, there may be a critical threshold where additional tests may result in diminishing returns. Regardless, we recommend on-going PCR testing as a public health intervention accompanying concurrent COVID-19 and influenza vaccination with the added caveat that sensitivity analyses will be necessary to determine the optimal thresholds for both testing and vaccine coverage. Overall, our results suggest that rates of COVID-19 vaccination and PCR testing capacity are important factors for reducing absenteeism, while the influenza vaccination rate and the transmission rates for both COVID-19 and influenza have lower and almost equal affect on absenteeism. We also use the model to estimate and quantify the (indirect) benefit that influenza immunization confers against COVID-19 transmission.

Esophageal and gastric malignancies after bariatric surgery: a retrospective global study.

BACKGROUND: Bariatric surgery can influence the presentation, diagnosis, and management of gastrointestinal cancers. Esophagogastric (EG) malignancies in patients who have had a prior bariatric procedure have not been fully characterized. OBJECTIVE: To characterize EG malignancies after bariatric procedures. SETTING: University Hospital, United Kingdom. METHODS: We performed a retrospective, multicenter observational study of patients with EG malignancies after bariatric surgery to characterize this condition. RESULTS: This study includes 170 patients from 75 centers in 25 countries who underwent bariatric procedures between 1985 and 2020. At the time of the bariatric procedure, the mean age was 50.2 ± 10 years, and the mean weight 128.8 ± 28.9 kg. Women composed 57.3% (n = 98) of the population. Most (n = 64) patients underwent a Roux-en-Y gastric bypass (RYGB) followed by adjustable gastric band (AGB; n = 46) and sleeve gastrectomy (SG; n = 43). Time to cancer diagnosis after bariatric surgery was 9.5 ± 7.4 years, and mean weight at diagnosis was 87.4 ± 21.9 kg. The time lag was 5.9 ± 4.1 years after SG compared to 9.4 ± 7.1 years after RYGB and 10.5 ± 5.7 years after AGB. One third of patients presented with metastatic disease. The majority of tumors were adenocarcinoma (82.9%). Approximately 1 in 5 patients underwent palliative treatment from the outset. Time from diagnosis to mortality was under 1 year for most patients who died over the intervening period. CONCLUSION: The Oesophago-Gastric Malignancies After Obesity/Bariatric Surgery study presents the largest series to date of patients developing EG malignancies after bariatric surgery and attempts to characterize this condition.

Robotic versus laparoscopic median arcuate ligament (MAL) release: a retrospective comparative study.

BACKGROUND: Multiple retrospective studies have demonstrated the safety and feasibility of laparoscopic median arcuate ligament division with celiac neurolysis for the definitive management of median arcuate ligament syndrome (MALS). This study queries the clinical equipoise of robotic (RMALR) versus laparoscopic MAL release (LMALR) at a high-volume center. METHODS: A retrospective analysis of consecutive 26 RMALR and 24 LMALR between March 2018 and August 2019 by a single surgeon at a quaternary academic institution was completed. Primary endpoint was postoperative decrease in celiac trunk expiratory peak systolic velocities (PSVs) measured by mesenteric duplex ultrasonography. Secondary outcomes included reported improvement in MALS-related clinical symptoms, distribution of first assistant seniority level, and involvement of second assistants in RMALR versus LMALR. RESULTS: Mean operative times for LMALR and RMALR were 86 and 134 min, respectively (p < 0.0001). There were no open conversions and mean length of hospital stay was 1 day for both cohorts. Both groups provided an equally effective decrease in postoperative peak systolic velocities (PSVs) (LMALR p = 0.0011; RMALR p = 0.0022; LMALR vs. RMALR p = 0.7772). While RMALR had significantly higher reduction of chronic abdominal pain postoperatively, there were no significant differences in other postoperative symptom relief between groups. However, RMALR patients reported significant relief of postprandial abdominal pain (p < 0.0001) and chronic nausea (p = 0.0002). RMALR had significantly more junior first assistants (p = 0.0001) and less frequently required second assistants compared to LMALR (p = 0.0381). CONCLUSIONS: In this study comparing RMALR to LMALR, postoperative chronic abdominal pain relief was significantly less in the former while other outcomes were equivalent. In comparison with LMALR, RMALR cases were associated with more junior first assistants, fewer second assistants, and longer operative times. Both approaches are safe and feasible for well-selected patients in experienced centers.

TLE4 Is a Critical Mediator of Osteoblast and Runx2-Dependent Bone Development.

Healthy bone homeostasis hinges upon a delicate balance and regulation of multiple processes that contribute to bone development and metabolism. While examining hematopoietic regulation by Tle4, we have uncovered a previously unappreciated role of Tle4 on bone calcification using a novel Tle4 null mouse model. Given the significance of osteoblasts in both hematopoiesis and bone development, this study investigated how loss of Tle4 affects osteoblast function. We used dynamic bone formation parameters and microCT to characterize the adverse effects of Tle4 loss on bone development. We further demonstrated loss of Tle4 impacts expression of several key osteoblastogenic genes, including Runx2, Oc, and Ap, pointing toward a potential novel mechanism for Tle4-dependent regulation of mammalian bone development in collaboration with the RUNX family members.

Bariatric Surgery is Safe for Patients After Recovery from COVID-19.

BACKGROUND: Studies of patients who have undergone surgery while infected with COVID-19 have shown increased risks for adverse outcomes in both pulmonary complications and mortality. It has become clear that the risk of complications from perioperative COVID-19 infection must be weighed against the risk from delayed surgical treatment. Studies have also shown that prior bariatric surgery conveys protection against mortality from COVID-19 and that obesity is the biggest risk factor for mortality from COVID-19 infection in adults under 45 years of age. Studies in patients who have fully recovered from COVID-19 and underwent elective surgery have not become widely available yet. OBJECTIVES: This multi-institutional case series is presented to highlight patients who developed COVID-19, fully recovered, and subsequently underwent elective bariatric surgery with 30-day outcomes available. SETTING: Nine bariatric surgery centers located across the United States. METHODS: This multicenter case series is a retrospective chart review of patients who developed COVID-19, recovered, and subsequently underwent bariatric surgery. Fifty-three patients are included, and 30-day morbidity and mortality were analyzed. RESULTS: Thirty-day complications included esophageal spasm, dehydration, and ileus. There were no cardiovascular, venous thromboembolism (VTE) or respiratory events reported. There were no 30- day mortalities. CONCLUSIONS: Bariatric surgery has been safely performed in patients who made a full recovery from COVID-19 without increased complications due to cardiovascular, pulmonary, venous thromboembolism, or increased mortality rates.

Efficacy and effectiveness of high-dose influenza vaccine in older adults by circulating strain and antigenic match: An updated systematic review and meta-analysis.

BACKGROUND: Influenza vaccine efficacy/effectiveness can vary from season to season due in part to the dominant circulating strains and antigenic matching. This study reviews the relative vaccine efficacy/effectiveness (rVE) of high-dose inactivated trivalent influenza vaccine (HD-IIV3) compared to standard-dose influenza vaccines (SD-IIV) in adults aged ≥ 65 years against influenza-associated outcomes. Additional sub-analyses of HD-IIV3 rVE were performed by the predominantly circulating influenza strain and the antigenic match or mismatch of the vaccine against the predominant circulating strains. METHODS: An updated systematic review and meta-analysis was conducted for studies assessing the rVE of HD-IIV3 against probable/laboratory-confirmed influenza-like illness (ILI), hospital admissions, and death in adults aged ≥ 65 years. Results from individual seasons were extracted from the studies, and viral surveillance data were used to determine the dominant circulating strains and antigenic match for each season. Results were then stratified based on clinical outcomes and seasonal characteristics and meta-analyzed to estimate pooled rVEs of HD-IIV3. RESULTS: 15 publications were meta-analyzed after screening 1,293 studies, providing data on 10 consecutive influenza seasons and over 22 million individuals receiving HD-IIV3 in randomized and observational settings. Across all influenza seasons, HD-IIV3 demonstrated improved protection against ILI compared to SD-IIV (rVE = 15.9%, 95% CI: 4.1-26.3%). HD-IIV3 was also more effective at preventing hospital admissions from all-causes (rVE = 8.4%, 95% CI: 5.7-11.0%), as well as influenza (rVE = 11.7%, 95% CI: 7.0-16.1%), pneumonia (rVE = 27.3%, 95% CI: 15.3-37.6%), combined pneumonia/influenza (rVE = 13.4%, 95% CI: 7.3-19.2%) and cardiorespiratory events (rVE = 17.9%, 95% CI: 15.0-20.8%). Reductions in mortality due to pneumonia/influenza (rVE = 39.9%, 95% CI: 18.6-55.6%) and cardiorespiratory causes (rVE = 27.7%, 95% CI: 13.2-32.0%) were also observed. Similar pooled rVEs were observed in both matched and mismatched seasons and in seasons where A/H3N2 or A/H1N1 strains were predominantly circulating. CONCLUSIONS: Evidence over 10 consecutive influenza seasons and in more than 34 million individuals aged ≥ 65 years suggests that HD-IIV3 is consistently more effective than SD-IIV at reducing influenza cases as well as influenza-associated clinical complications irrespective of circulating strain and antigenic match. A video summary of the article can be accessed via the Supplementary data link at the end of this article.

Efficacy of Virtual Case-Based General Surgery Clerkship Curriculum During COVID-19 Distancing.

OBJECTIVE: The COVID-19 pandemic created a paradigm shift in medical education with a reliance upon alternative teaching methods to deliver meaningful surgery clerkship content. This study examines the efficacy of a novel, case-based virtual surgery clerkship curriculum to determine its impact on student experience during quarantine. STUDY DESIGN: Sixteen third-year medical students enrolled in the General Surgery clerkship between April through June 2020 during COVID-19 distancing at a quaternary medical center (Cleveland Clinic, Cleveland, OH) participated in this study. Course surveys, including a 10-question curriculum-based multiple-choice assessment, were administered before and after the clerkship. Analyses include student self-perception of readiness to see a surgical consult independently, students' interest in pursuing a General Surgery residency, and improvement of surgical knowledge. RESULTS AND CONCLUSION: On a 5-point Likert scale, students felt significantly more assured in their ability to independently assess a surgical consult by the end of the course. Five (31%) students reported an influence of the curriculum on their personal interest in a career in General Surgery. Mean scores on the curriculum-based knowledge assessment increased. These findings highlight that a virtual platform can be a reliable alternative adjunct that delivers surgical content and positively impacts student experience. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40670-020-01126-5.

Effect modification of resident autonomy and seniority on perioperative outcomes in laparoscopic cholecystectomy.

BACKGROUND: Resident operative involvement is an integral aspect of general surgery residency training. However, current data examining the effect of resident autonomy on perioperative outcomes remain limited. METHODS: Patient and operator-specific data were collected from 344 adult laparoscopic cholecystectomies at a tertiary academic institution and its regional affiliates between 2018 and 2019. Multivariate modeling compared postoperative outcomes between cases completed with or without resident involvement and its effect modification by resident seniority and autonomy per Zwisch scale. Outcomes include 30-day postoperative complications, hospital readmission rate, and operative time. RESULTS: Multivariate analysis revealed resident involvement in laparoscopic cholecystectomy did not significantly change odds of 30-day postoperative complications (OR 2.52, p = 0.185, 95% CI 0.64-9.92) or hospital readmission (OR 1.61, p = 0.538, 95% CI 0.36-7.23). Operative time is significantly increased compared to faculty-only cases (IRR 1.37, p < 0.001, 95% CI 1.26-1.48). While accounting for case difficulty and resident performance evaluated by SIMPL criteria, stratification by resident autonomy measured by Zwisch scale or seniority reveal no effect modification on 30-day postoperative complications, readmissions, or operative time. The effect of resident involvement on longer relative rates of operative time loses its significance in supervision-only cases (IRR 1.18, p = 0.069, 95% CI 0.99-1.41). CONCLUSION: While resident involvement and autonomy are associated with significantly longer operative times in laparoscopic cholecystectomy, their lack of significant effect on postoperative outcomes argues strongly for continued resident involvement and supervised operative independence.

Beyond Medical Knowledge and Patient Care: A Program Director's Perspective for the Role of General Surgery Subinternships.

OBJECTIVE: Established primary goals of general surgery subinternships are improvement in patient care and medical knowledge. However, the secondary gains such as obtaining recommendation letters and forming relationships are apparent but poorly defined. We sought the opinion of general surgery program directors (PDs) on the secondary purposes of subinternships. Our aim is to aide mentors and students to optimize the subinternship experience relative to the residency application process. DESIGN: A survey was administered in July 2019. This questionnaire consisted of 11 items and was broken down into 3 sections: demographics, PD perspective on the secondary goals of a general surgery subinternship, and the role of general surgery subinternships on the students' residency application. SETTING: An online, national survey through the Association for Program Directors listserv. PARTICIPANTS: United States general surgery PDs affiliated with the Association for Program Directors listserv. RESULTS: Sixty-one PDs completed the survey from 42 (69%) academic and 14 (23%) community programs. The majority of PDs (n = 33, 54%) reported that assessment of a subintern's suitability for their residency was the most important secondary purpose. Furthermore, PDs (n = 24, 39%) valued a letter of recommendation from faculty the student worked with during a subinternship as the most important criteria in the interview selection process. Away rotations were perceived as of equal value to subinternships completed at the student's home institution. Overall, PD opinions were similar at academic and community programs. CONCLUSIONS: Our study suggests subinternships significantly impact a student's application to general surgery residency, clarifying a secondary role for these rotations. Subinternships are important for PDs to assess a student for ranking at their program. All students should pursue a letter of recommendation from subinternship faculty, when possible, as they can heavily influence the interview selection process. Away rotations should only be recommended for those students who need to strengthen their application.

Quantifying the annual incidence and underestimation of seasonal influenza: A modelling approach.

BACKGROUND: Seasonal influenza poses a significant public health and economic burden, associated with the outcome of infection and resulting complications. The true burden of the disease is difficult to capture due to the wide range of presentation, from asymptomatic cases to non-respiratory complications such as cardiovascular events, and its seasonal variability. An understanding of the magnitude of the true annual incidence of influenza is important to support prevention and control policy development and to evaluate the impact of preventative measures such as vaccination. METHODS: We use a dynamic disease transmission model, laboratory-confirmed influenza surveillance data, and randomized-controlled trial (RCT) data to quantify the underestimation factor, expansion factor, and symptomatic influenza illnesses in the US and Canada during the 2011-2012 and 2012-2013 influenza seasons. RESULTS: Based on 2 case definitions, we estimate between 0.42-3.2% and 0.33-1.2% of symptomatic influenza illnesses were laboratory-confirmed in Canada during the 2011-2012 and 2012-2013 seasons, respectively. In the US, we estimate between 0.08-0.61% and 0.07-0.33% of symptomatic influenza illnesses were laboratory-confirmed in the 2011-2012 and 2012-2013 seasons, respectively. We estimated the symptomatic influenza illnesses in Canada to be 0.32-2.4 million in 2011-2012 and 1.8-8.2 million in 2012-2013. In the US, we estimate the number of symptomatic influenza illnesses to be 4.4-34 million in 2011-2012 and 23-102 million in 2012-2013. CONCLUSIONS: We illustrate that monitoring a representative group within a population may aid in effectively modelling the transmission of infectious diseases such as influenza. In particular, the utilization of RCTs in models may enhance the accuracy of epidemiological parameter estimation.

Effects of laparoscopic vs open abdominal surgery on costs and hospital readmission rate and its effect modification by surgeons' case volume.

BACKGROUND: Laparoscopy provides a minimally invasive alternative to open abdominal surgery. Current data describing its association with hospital readmission and costs in relation to surgeon laparoscopic case volume is limited to smaller databases and subsets of operations. METHODS: This retrospective cohort study of 23,285 adult abdominal operations from 2007 to 2015 compares 30-day readmission rate and costs between laparoscopic and open abdominal operations and examines effect modification by surgeon laparoscopic case volume. Outcomes were all-cause hospital readmission within 30 days after discharge and index hospital admission cost. RESULTS: All-cause hospital readmission rates were significantly lower after laparoscopic abdominal operations compared with open operations (adjusted odds ratio [aOR] 0.56, 95% CI 0.46-0.69, p < 0.001) with a difference in readmission risk attributable to laparoscopic approach of - 4.0% (95% CI - 5.4 to - 2.6%) in complete-case analysis. Among surgeons with a high laparoscopic case volume, the estimated difference in readmission risk through laparoscopy was magnified (- 5.8%, 95% CI - 7.5 to - 4.1%) compared to low surgeon laparoscopic case volume (- 2.9%, 95% CI - 4.8 to -1.1%, p for interaction = 0.005). The estimated difference in costs of the index hospital admission attributable to laparoscopic approach was - $3869 (95% CI - $4200 to - $3538; adjusted incidence rate ratio 0.77, 95% CI 0.75-0.79, p < 0.001). Laparoscopy was followed by significantly lower rates of readmissions related to gastrointestinal (aOR 0.68, 95% CI 0.55-0.85, p = 0.001), wound complications (infection: aOR 0.33, 95% CI 0.23-0.47, p < 0.001; non-infectious: aOR 0.47, 95% CI 0.30-0.74, p = 0.001), and malignancy (aOR 0.68, 95% CI 0.55-0.85, p < 0.001). The findings remain robust after multiple imputation and sensitivity analyses. CONCLUSIONS: Laparoscopy versus open abdominal surgery is associated with reduced hospital readmissions related to malignancy, gastrointestinal, and wound complications. Effect modification by higher laparoscopy case volume argues for continued proliferation of laparoscopy in abdominal surgeries.

Tumor Lysis Syndrome After Bilobectomy for Typical Carcinoid Tumor of the Lung.

Tumor lysis syndrome is a life-threatening complication comprising hyperuricemia, hyperkalemia, hyperphosphatemia, and hypocalcemia attributed to release of intracellular contents. Although traditionally associated with leukemia and lymphoma after chemotherapy, it is known to occur in solid malignancies. We herein report a rare case of this syndrome after resection of bulky carcinoid tumor of the lung.

Acellular pertussis vaccines effectiveness over time: A systematic review, meta-analysis and modeling study.

BACKGROUND: Acellular pertussis vaccine studies postulate that waning protection, particularly after the adolescent booster, is a major contributor to the increasing US pertussis incidence. However, these studies reported relative (ie, vs a population given prior doses of pertussis vaccine), not absolute (ie, vs a pertussis vaccine naïve population) efficacy following the adolescent booster. We aim to estimate the absolute protection offered by acellular pertussis vaccines. METHODS: We conducted a systematic review of acellular pertussis vaccine effectiveness (VE) publications. Studies had to comply with the US schedule, evaluate clinical outcomes, and report VE over discrete time points. VE after the 5-dose childhood series and after the adolescent sixth-dose booster were extracted separately and pooled. All relative VE estimates were transformed to absolute estimates. VE waning was estimated using meta-regression modeling. FINDINGS: Three studies reported VE after the childhood series and four after the adolescent booster. All booster studies reported relative VE (vs acellular pertussis vaccine-primed population). We estimate initial childhood series absolute VE is 91% (95% CI: 87% to 95%) and declines at 9.6% annually. Initial relative VE after adolescent boosting is 70% (95% CI: 54% to 86%) and declines at 45.3% annually. Initial absolute VE after adolescent boosting is 85% (95% CI: 84% to 86%) and declines at 11.7% (95% CI: 11.1% to 12.3%) annually. INTERPRETATION: Acellular pertussis vaccine efficacy is initially high and wanes over time. Observational VE studies of boosting failed to recognize that they were measuring relative, not absolute, VE and the absolute VE in the boosted population is better than appreciated.