Differences between patients in whom physicians agree versus disagree about the preoperative diagnosis of heart failure.

STUDY OBJECTIVE: To quantify preoperative heart failure (HF) diagnostic agreement and identify characteristics of patients in whom physicians agreed versus disagreed about the diagnosis. DESIGN: Observational cohort study. SETTING: Patients undergoing major non-cardiac surgery at an academic center between 2015 and 2019. PATIENTS: 40,659 patients undergoing major non-cardiac surgery, among which a stratified subsample of 1018 patients with and without documented HF was reviewed. INTERVENTIONS: Via a panel of physicians frequently managing patients with HF (cardiologists, cardiac anesthesiologists, intensivists), detailed chart reviews were performed (two per patient; median review time 32 min per reviewer per patient) to render adjudicated HF diagnoses. MEASUREMENTS: Adjudicated diagnostic agreement measures (percent agreement, Krippendorf's alpha) and univariate comparisons (standardized differences) between patients in whom physicians agreed versus disagreed about the preoperative HF diagnosis. MAIN RESULTS: Among patients with documented HF, physicians agreed about the diagnosis in 80.0% of cases (consensus positive), disagreed in 13.8% (disagreement), and refuted the diagnosis in 6.3% (consensus negative). Conversely, among patients without documented HF, physicians agreed about the diagnosis in 88.0% (consensus negative), disagreed in 8.4% (disagreement), and refuted the diagnosis in 3.6% (consensus positive). The estimated agreement for the 40,659 cases was 91.1% (95% CI 88.3%-93.9%); Krippendorff's alpha was 0.77 (0.75-0.80). Compared to patients in whom physicians agreed about a HF diagnosis, patients in whom physicians disagreed exhibited fewer guideline-defined HF diagnostic criteria. CONCLUSIONS: Physicians usually agree about HF diagnoses adjudicated via chart review, although disagreement is not uncommon and may be partly explained by heterogeneous clinical presentations. Our findings inform preoperative screening processes by identifying patients whose characteristics contribute to physician disagreement via chart review. Clinical Trial Number / Registry URL: Not applicable.

Tracheostomy, Feeding-Tube, and In-Hospital Postoperative Mortality in Children: A Retrospective Cohort Study.

BACKGROUND: Neuromuscular/neurologic disease confers increased risk of perioperative mortality in children. Some patients require tracheostomy and/or feeding tubes to ameliorate upper airway obstruction or respiratory failure and reduce aspiration risk. Empiric differences between patients with and without these devices and their association with postoperative mortality have not been previously assessed. METHODS: This retrospective cohort study using the Pediatric Health Information System measured 3- and 30-day in-hospital postsurgical mortality among children 1 month to 18 years of age with neuromuscular/neurologic disease at 44 US children's hospitals, from April 2016 to October 2018. We summarized differences between patients presenting for surgery with and without these devices using standardized differences. Then, we calculated 3- and 30-day mortality among patients with tracheostomy, feeding tube, both, and neither device, overall and stratified by important exposures, using Fisher exact test to test whether differences were significant. RESULTS: There were 43,193 eligible patients. Unadjusted 3-day mortality was 1.3% (549/43,193); 30-day mortality was 2.7% (1168/43,193). Most (79.1%) used neither a feeding tube or tracheostomy, 1.2% had tracheostomy only, 15.5% had feeding tube only, and 4.2% used both devices. Compared to children with neither device, children using either or both devices were more likely to have multiple CCCs, dysphagia, chronic pulmonary disease, cerebral palsy, obstructive sleep apnea, or malnutrition, and a prolonged intensive care unit (ICU) stay within the previous year. They were less likely to present for high-risk surgeries (33% vs 57%). Having a feeding tube was associated with decreased 3-day mortality overall compared to having neither device (0.9% vs 1.3%, P = .003), and among children having low-risk surgery, and surgery during urgent or emergent hospitalizations. Having both devices was associated with decreased 3-day mortality among children having low-risk surgery (0.8% vs 1.9%; P = .013), and during urgent or emergent hospitalizations (1.6% vs 2.9%; P = .023). For 30-day mortality, having a feeding tube or both devices was associated with lower mortality when the data were stratified by the number of CCCs. CONCLUSIONS: Patients requiring tracheostomy, feeding tube, or both are generally sicker than patients without these devices. Despite this, having a feeding tube was associated with lower 3-day mortality overall and lower 30-day mortality when the data were stratified by the number of CCCs. Having both devices was associated with lower 3-day mortality in patients presenting for low-risk surgery, and surgery during urgent or emergent hospitalizations.

Association of Anesthesiologist Staffing Ratio With Surgical Patient Morbidity and Mortality.

Importance: Recent studies have investigated the effect of overlapping surgeon responsibilities or nurse to patient staffing ratios on patient outcomes, but the association of overlapping anesthesiologist responsibilities with patient outcomes remains unexplored to our knowledge. Objective: To examine the association between different levels of anesthesiologist staffing ratios and surgical patient morbidity and mortality. Design, Setting, and Participants: A retrospective, matched cohort study consisting of major noncardiac inpatient surgical procedures performed from January 1, 2010, to October 31, 2017, was conducted in 23 US academic and private hospitals. A total of 866 453 adult patients (aged ≥18 years) undergoing major inpatient surgery within the Multicenter Perioperative Outcomes Group electronic health record registry were included. Anesthesiologist sign-in and sign-out times were used to calculate a continuous time-weighted average staffing ratio variable for each operation. Propensity score-matching methods were applied to create balanced sample groups with respect to patient-, operative-, and hospital-level confounders and resulted in 4 groups based on anesthesiologist staffing ratio. Groups consisted of patients receiving care from an anesthesiologist covering 1 operation (group 1), more than 1 to no more than 2 overlapping operations (group 1-2), more than 2 to no more than 3 overlapping operations (group 2-3), and more than 3 to no more than 4 overlapping operations (group 3-4). Data analysis was performed from October 2019 to October 2021. Exposure: Undergoing a major inpatient surgical operation that involved an anesthesiologist providing care for up to 4 overlapping operations. Main Outcomes and Measures: The primary composite outcome was 30-day mortality and 6 major surgical morbidities (cardiac, respiratory, gastrointestinal, urinary, bleeding, and infectious complications) derived from International Classification of Diseases, Ninth Revision and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision discharge diagnosis codes. Results: In all, 578 815 adult patients (mean [SD] age, 55.7 [16.2] years; 55.1% female) were analyzed. After matching operations according to anesthesiologist staffing ratio, 48 555 patients were in group 1; 247 057, group 1-2; 216 193, group 2-3; and 67 010, group 3-4. Increasing anesthesiologist coverage responsibilities was associated with an increase in risk-adjusted surgical patient morbidity and mortality. Compared with patients in group 1-2, those in group 2-3 had a 4% relative increase in risk-adjusted mortality and morbidity (5.06% vs 5.25%; adjusted odds ratio [AOR], 1.04; 95% CI, 1.01-1.08; P = .02) and those in group 3-4 had a 14% increase in risk-adjusted mortality and morbidity (5.06% vs 5.75%; AOR, 1.15; 95% CI, 1.09-1.21; P < .001). Conclusions and Relevance: This study's findings suggest that increasing overlapping coverage by anesthesiologists is associated with increased surgical patient morbidity and mortality. Therefore, the potential effects of staffing ratios in perioperative team models should be considered in clinical coverage efforts.

Preoperative clinical diagnostic accuracy of heart failure among patients undergoing major noncardiac surgery: a single-centre prospective observational analysis.

Background: Reliable diagnosis of heart failure during preoperative evaluation is important for perioperative management and long-term care. We aimed to quantify preoperative heart failure diagnostic accuracy and explore characteristics of patients with heart failure misdiagnoses. Methods: We performed an observational cohort study of adults undergoing major noncardiac surgery at an academic hospital between 2015 and 2019. A preoperative clinical diagnosis of heart failure was defined using keywords from the history and clinical examination or administrative documentation. Across stratified subsamples of cases with and without clinically diagnosed heart failure, health records were intensively reviewed by an expert panel to develop an adjudicated heart failure reference standard using diagnostic criteria congruent with consensus guidelines. We calculated agreement among experts, and analysed performance of clinically diagnosed heart failure compared with the adjudicated reference standard. Results: Across 40 555 major noncardiac procedures, a stratified subsample of 511 patients was reviewed by the expert panel. The prevalence of heart failure was 9.1% based on clinically diagnosed compared with 13.3% (95% confidence interval [CI], 10.3-16.2%) estimated by the expert panel. Overall agreement and inter-rater reliability (kappa) among heart failure experts were 95% and 0.79, respectively. Based upon expert adjudication, heart failure was clinically diagnosed with an accuracy of 92.8% (90.6-95.1%), sensitivity 57.4% (53.1-61.7%), specificity 98.3% (97.1-99.4%), positive predictive value 83.5% (80.3-86.8%), and negative predictive value 93.8% (91.7-95.9%). Conclusions: Limitations exist to the preoperative clinical diagnosis of heart failure, with nearly half of cases undiagnosed preoperatively. Considering the risks of undiagnosed heart failure, efforts to improve preoperative heart failure diagnoses are warranted.

Virtual Reality Analgesia in Labor: The VRAIL Pilot Study-A Preliminary Randomized Controlled Trial Suggesting Benefit of Immersive Virtual Reality Analgesia in Unmedicated Laboring Women.

This pilot study investigated the use of virtual reality (VR) in laboring women. Twenty-seven women were observed for equivalent time during unmedicated contractions in the first stage of labor both with and without VR (order balanced and randomized). Numeric rating scale scores were collected after both study conditions. Significant decreases in sensory pain -1.5 (95% CI, -0.8 to -2.2), affective pain -2.5 (95% CI, -1.6 to -3.3), cognitive pain -3.1 (95% CI, -2.4 to -3.8), and anxiety -1.5 (95% CI, -0.8 to -2.3) were observed during VR. Results suggest that VR is a potentially effective technique for improving pain and anxiety during labor.

Metabolic Parameters, Weight Loss, and Comorbidities 4 Years After Roux-en-Y Gastric Bypass and Sleeve Gastrectomy.

BACKGROUND: Sleeve gastrectomy (LSG) is now the predominant bariatric surgery performed, yet there is limited long-term data comparing important outcomes between LSG and Roux-en-Y gastric bypass (RYGB). This study compares weight loss and impact on comorbidities of the two procedures. METHODS: We retrospectively evaluated weight, blood pressure, hemoglobin A1c, cholesterol, and medication use for hypertension, diabetes, and hyperlipidemia at 1-4 years post-operatively in 380 patients who underwent RYGB and 334 patients who underwent LSG at the University of Michigan from January 2008 to November 2013. Follow-up rates from 714 patients initially were 657 (92%), 556 (78%), 507 (71%), and 498 (70%) at 1-4 years post-operatively. RESULTS: Baseline characteristics were similar except for higher weight and BMI in LSG. There was greater weight loss with RYGB vs. LSG at all points. Hemoglobin A1c and total cholesterol improved more in RYGB vs. LSG at 4 years. There was greater remission of hypertension and discontinuation of all medications for hypertension and diabetes with RYGB at 4 years. CONCLUSIONS: Weight loss, reduction in medications for hypertension and diabetes, improvements in markers of diabetes and hyperlipidemia, and remission rates of hypertension were superior with RYGB vs. LSG 4 years post-operatively. Choice of bariatric procedures should be tailored to surgical risk, comorbidities, and weight loss goals.

Factors Associated With Achieving a Body Mass Index of Less Than 30 After Bariatric Surgery.

IMPORTANCE: Achieving a body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) of less than 30 is an important goal of bariatric surgery, given the increased risk for weight-related morbidity and mortality with a BMI above this threshold. OBJECTIVE: To identify predictors for achieving a BMI of less than 30 after bariatric surgery. DESIGN, SETTING, AND PARTICIPANTS: This retrospective study used data from the Michigan Bariatric Surgery Collaborative, a statewide quality improvement collaborative that uses a prospectively gathered clinical data registry. A total of 27 320 adults undergoing primary bariatric surgery between June 2006 and May 2015 at teaching and nonteaching hospitals in Michigan were included. EXPOSURE: Bariatric surgery. MAIN OUTCOMES AND MEASURES: Logistic regression was used to identify predictors for achieving a BMI of less than 30 at 1 year after surgery. Secondary outcome measures included 30-day postoperative complications and 1-year self-reported comorbidity remission. RESULTS: A total of 9713 patients (36%; mean [SD] age, 46.9 [11.3] years; 16.6% male) achieved a BMI of less than 30 at 1 year after bariatric surgery. A significant predictor for achieving this goal was a preoperative BMI of less than 40 (odds ratio [OR], 12.88; 95% CI, 11.71-14.16; P < .001). Patients who had a sleeve gastrectomy, gastric bypass, or duodenal switch were more likely to achieve a BMI of less than 30 compared with those who underwent adjustable gastric banding (OR, 8.37 [95% CI, 7.44-9.43]; OR, 21.43 [95% CI, 18.98-24.19]; and OR, 82.93 [95% CI, 59.78-115.03], respectively; P < .001). Only 8.5% of patients with a BMI greater than 50 achieved a BMI of less than 30 after bariatric surgery. Patients who achieved a BMI of less than 30 had significantly higher reported rates of medication discontinuation for hyperlipidemia (60.7% vs 43.2%, P < .001), diabetes (insulin: 67.7% vs 50.0%, P < .001; oral medications: 78.5% vs 64.3%, P < .001), and hypertension (54.7% vs 34.6%, P < .001), as well as a significantly higher rate of sleep apnea remission (72.5% vs 49.3%, P < .001) and higher satisfaction rate (92.8% vs 78.0%, P < .001) compared with patients who did not. CONCLUSIONS AND RELEVANCE: Patients with a preoperative BMI of less than 40 are more likely to achieve a BMI of less than 30 after bariatric surgery and are more likely to experience comorbidity remission. Policies and practice patterns that delay bariatric surgery until the BMI is 50 or greater can result in significantly inferior outcomes.

Milestone Weight Loss Goals (Weight Normalization and Remission of Obesity) after Gastric Bypass Surgery: Long-Term Results from the University of Michigan.

BACKGROUND: Rates of weight normalization and obesity remission after Roux-en-Y gastric bypass (GB) are unknown. This study evaluated weight loss, rates of achieving body mass index (BMI) <25 or 30 kg/m2, recidivism, and predictors of success following GB. METHODS: We retrospectively studied weight and BMI at baseline, 2 and 6 months, and annually at 1-7 years in 219 patients undergoing GB at the University of Michigan from January 2008 to November 2010. RESULTS: Follow-up was excellent for a population traditionally associated with high attrition rates with data availability of 157/219, 145/219, 144/219, 134/219, 123/219, 82/161, and 29/64 patients at 1-7 years, respectively. Mean baseline BMI was 47.0 kg/m2. Weight normalization (BMI <25 kg/m2) occurred in 2.3-6.8% of patients. More importantly, 47% of patients achieved remission of obesity (BMI <30 kg/m2) at some time point and 24% (52/219) at the last observed time point. BMI <30 kg/m2 was associated with a lower initial BMI and follow-up for more than 2 years. CONCLUSIONS: Rates of weight normalization are low after GB; however, a large number of patients achieved BMI <30 kg/m2. While the percent total weight loss and excess weight loss are both quite high in the entire cohort and this is likely associated with significant health benefits, our results still underscore the need to address obesity with intensive clinical attention earlier in its course.

Evaluating the effect of operative technique on leaks after laparoscopic sleeve gastrectomy: a case-control study.

OBJECTIVE: To assess the effect of operative technique on staple line leaks after laparoscopic sleeve gastrectomy (LSG). BACKGROUND: Staple-line leaks after LSG are a major source of morbidity and mortality. Variations in operative technique exist; however, their effect on leaks is poorly understood. METHODS: We analyzed data from the Michigan Bariatric Surgery Collaborative (MBSC) to perform a case-control study comparing patients who had a clinically significant leak after undergoing a primary LSG to those who did not. A total of 45 patients with leaks were identified between January 2007 and December 2013. The leak group was matched 1:2 to a control group based on procedure type, age, body mass index, sex, and year the procedure was performed. Technique-specific factors were assessed by reviewing operative notes from all primary bariatric procedures in our study population. Conditional logistic regression was used to identify techniques associated with leaks. To increase the power of our analysis, we used a significance level of .10. RESULTS: Leak rates with LSG have decreased over the past 5 years (1.18% to .36%) as annual case volume has increased (846 cases/yr to 4435 cases/yr). Surgeons who performed 43 or more cases per year had a leak rate<1%. Leaks were more common among cases requiring a blood transfusion (26.2% versus 1.08%, P = .0031) and when cases were converted to open surgery (7.14% versus 0%, P = .0741). However, there was no significant difference in operative time between cases involving a leak and their matched controls (95.4 min versus 87.1 min, P = .1197). Oversewing of the staple line was the only technique associated with less leaks after controlling for confounding factors (OR .397 CI .174, .909, P = .0665). Notably, surgeons who oversewed routinely were also found to have higher case volume (307 versus 140, P = .0216) and less overall complication rates (4.81% versus 7.95%, P = .0027). Furthermore, oversewing technique varied widely as only 22.6% of cases involved oversewing of the entire staple line. CONCLUSION: Despite considerable variation in operative technique, leak rates with laparoscopic sleeve gastrectomy have decreased over time as operative volume has increased. Oversewing of the staple line was associated with fewer leaks, but specific suturing technique was not uniform and oversewing was performed routinely by more experienced surgeons with higher case volumes and less complication rates overall. Before standardizing surgical technique one must take into account variations in surgeon skill and experience.

Roux-En-Y Gastric Bypass Vs. Sleeve Gastrectomy: Balancing the Risks of Surgery with the Benefits of Weight Loss.

BACKGROUND: The purpose of the study was to compare weight loss, metabolic parameters, and postoperative complications in patients undergoing Roux-en-Y gastric bypass (GB) and sleeve gastrectomy (SG). METHODS: We retrospectively studied 30-day postoperative complications as well as change in weight, blood pressure, cholesterol, hemoglobin, hemoglobin A1C, and creatinine from baseline to 2, 6, 12, and 24 months postoperatively in 383 patients undergoing GB and 336 patients undergoing SG at the University of Michigan from January 2008 to November 2013. For a study population which typically has high attrition rates, there were excellent follow-up rates (706/719 at 2 months, 566/719 at 6 months, 519/719 at 12 months, and 382/719 at 24 months). RESULTS: Baseline characteristics were similar in both groups except for higher weight and BMI in the SG group. The GB group experienced greater total body weight loss at 6, 12, and 24 months (41.9 vs. 34.6 kg at 24 months, p < 0.0001). Excess weight loss was 69.7 and 51.7 % following GB and SG respectively at 24 months (p < 0.0001). BP improved significantly in both groups. Surgical complication rates were greater after GB (10.1 vs. 3.5 %, p = 0.0007) with no significant difference in life-threatening or potentially life-threatening complications. CONCLUSIONS: Weight loss was greater following GB compared to SG at 2 years. The risk for surgical complications was greater following GB. Surgical intervention should be tailored to surgical risk, comorbidities, and desired weight loss.

Technique or technology? Evaluating leaks after gastric bypass.

OBJECTIVE: To assess the relationship between technique and surgical devices on anastomotic and staple-line leaks after laparoscopic Roux-en-Y gastric bypass. BACKGROUND: Leaks after bariatric surgery remain a major source of morbidity and mortality. The association of surgical technique and devices with leaks after gastric bypass is poorly understood. SETTING: Multi-centered study that included teaching and non-teaching hospitals that participate in a statewide consortium for quality improvement using a payer-funded outcome registry. METHODS: We analyzed data from the Michigan Bariatric Surgery Collaborative and performed a case-control study comparing patients who sustained a leak with those who did not after primary laparoscopic Roux-en-Y gastric bypass. A total of 71 (.44%) patients with leaks were identified between January 2007 and December 2011. The leak group was matched 1:2 to a control group (nonleak) based on procedure type, age, body mass index, sex, and the year in which the procedure was performed. Technique-specific case characteristics and device-specific factors were assessed by reviewing operative notes from all primary bariatric procedures in our study population. RESULTS: The rate of leak decreased during the study period, and there was a significant downward trend (slope estimate: -.19961%, P = .0372). After performing multivariate analysis, the type of anastomosis (circular stapler, hand-sewn, or linear stapler) and stapler manufacturer were not associated with leaks. The use of buttressing material was associated with a higher rate of leaks (odds ratio: 8.79 [95% confidence interval: 2.49-31.01], P = .0007), whereas the use of fibrin sealant was associated with a lower rate of leaks (odds ratio .11 [95% confidence interval: .03-.41], P = .0013). These findings could not be explained by differences in measures of surgeon performance. CONCLUSION: Leak rates after laparoscopic gastric bypass have fallen in Michigan despite variations in technique and device utilization. Although the type of anastomosis and stapler manufacturer do not appear to be significantly associated with leaks, it appears that the use of buttressing material was more common in cases in which leaks occurred, whereas the use of fibrin sealant was not. Given the complex interplay of multiple variables that affect surgical outcomes, future studies justifying the benefits of operative devices should be evaluated prospectively in the context of surgeon technique and skill.

Effect of registration on cyclical kinematic data.

Given growing interest in functional data analysis (FDA) as a useful method for analyzing human movement data, it is critical to understand the effects of standard FDA procedures, including registration, on biomechanical analyses. Registration is used to reduce phase variability between curves while preserving the individual curve's shape and amplitude. The application of three methods available to assess registration could benefit those in the biomechanics community using FDA techniques: comparison of mean curves, comparison of average RMS values, and assessment of time-warping functions. Therefore, the present study has two purposes. First, the necessity of registration applied to cyclical data after time normalization is assessed. Second, we illustrate the three methods for evaluating registration effects. Masticatory jaw movements of 22 healthy adults (2 males, 21 females) were tracked while subjects chewed a gum-based pellet for 20s. Motion data were captured at 60 Hz with two gen-locked video cameras. Individual chewing cycles were time normalized and then transformed into functional observations. Registration did not affect mean curves and warping functions were linear. Although registration decreased the RMS, indicating a decrease in inter-subject variability, the difference was not statistically significant. Together these results indicate that registration may not always be necessary for cyclical chewing data. An important contribution of this paper is the illustration of three methods for evaluating registration that are easy to apply and useful for judging whether the extra data manipulation is necessary.