Abstract 143: Sepsis and Risk of Major Postoperative Vascular Complications

Introduction: Stroke, myocardial infarction (MI), and pulmonary embolism (PE) greatly increase postoperative morbidity and mortality. Sepsis has been linked to increased risk of major vascular events, but the risk related to sepsis exposure throughout the postoperative period is uncertain. Hypothesis: Perioperative sepsis exposure increases the 30-day risk of postoperative stroke, myocardial infarction (MI), and pulmonary embolism (PE). Methods: Data were obtained from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP), a formulaic sampling of surgical cases from participating United States institutions that prospectively collects demographic, clinical, surgical and 30-day outcome data. Sepsis was defined by systemic inflammatory response syndrome with either positive blood culture or evidence for infection found intraoperatively, and severe sepsis/shock as sepsis with evidence of organ dysfunction or circulatory dysfunction. We used mixed-effects Cox proportional hazard models, treating type of surgery as a random effect, to estimate the hazard ratios for major vascular complications due to sepsis and severe sepsis/shock exposure, adjusting for otherrisk factors. Results: We studied 6,614,937 surgical procedures. There were 201,230 cases with sepsis and an additional 78,052 cases of severe sepsis/shock. Outcomes included 13,939 strokes, 23,600 MIs, 21,893 PEs, and 1690 cases with multiple major vascular complications. Exposure to sepsis (HR 1.98, 95% confidence interval 1.91 to 2.06) or severe sepsis/shock (HR 3.27, 3.14 to 3.40) increased the risk of major vascular complications with larger effect than other established risks. Sepsis improvement within the preoperative period was associated with reduced risk (HR 0.82, 0.77 to 0.88). These findings were consistent in separate models for each complication. Conclusions: Sepsis approximately doubles and severe sepsis or shock triples the 30-day postoperative risk of major vascular complications. Improvement in sepsis severity prior to operation is associated with a 20% risk reduction.