IBC-Ox32 Streamlining preoperative risk assessment: counterintuitive results in the Bariatric patient

Abstract

Abstract Background Bariatric surgical operations continue to be performed in high numbers nationally, thus it is important to identify factors associated with post-surgical complications. This study aims to identify preoperative risk factors associated with bariatric surgery mortality. Methods A retrospective analysis was conducted on the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database to determine the strength of association between pre-operative exposures and 30-day mortality following bariatric surgery. A total of 701,265 primary bariatric operations were registered between the years of 2015 and 2017, consisting of sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), adjustable gastric band (AGB), and duodenal switch (DS) Results From the 701,265 surgeries registered in the database, 636,286 had complete data points for the variables of interest and therefore were included in this analysis. The mean age of the cohort was 45.01 (SD= 11.96) years, mean BMI was 45.54 kg/m2 (SD=7.72), and 80.07% were female. Overall 30-day mortality was 0.10% (n=629). The association between the following preoperative variables and mortality within 30 days of bariatric surgery was not statistically significant: hyperlipidemia, history of pulmonary embolism, oxygen dependence, obstructive sleep apnea and history of venous stasis. Smoking status (AOR=1.38), insulin dependent diabetes (AOR=1.37) and the use of more than 3 hypertensive medications (AOR=1.30) were weakly associated with postoperative mortality (p<0.05; CI=95%). History of chronic obstructive pulmonary disease (COPD; AOR=2.00), partial functional dependency (AOR=2.09), renal insufficiency (AOR=1.63), dialysis (AOR=3.15), history of deep venous thrombosis (AOR=1.78), history of myocardial infarction (AOR=1.65) and history of cardiac surgery (AOR=1.87) were strongly associated with mortality (P<0.05; c.i. = 95%) Conclusion Bariatric surgery continues to be safe. Many factors that have traditionally been thought to contribute to mortality, such as diabetes, hypertension, smoking, and oxygen dependence may have little impact. Other variables such as previous heart surgery, functional dependency status and COPD may play a bigger role in adverse outcomes. While these associations do not determine causality, understanding the strength of them can guide physicians on preoperative risk assessment and care.