Venous thromboembolism after surgery for inflammatory bowel disease: are there modifiable risk factors? Data from ACS NSQIP.

backgroundAlthough it is commonly reported that IBD patients are at increased risk for venous thromboembolic events, little real-world data exist regarding their postoperative incidence and related outcomes in everyday practice.

objectiveWe aimed to identify the rate of venous thromboembolism and modifiable risk factors within a large cohort of surgical IBD patients.

designWe performed a retrospective review of IBD patients who underwent colorectal procedures. PATIENTS: Patient data were obtained from the American College of Surgeons National Surgical Quality Improvement Program 2004 to 2010 Participant Use Data Files.

main outcome measuresThe primary outcomes measured were short-term (30-day) postoperative venous thromboembolism (deep vein thrombosis and pulmonary embolism). Clinical variables were analyzed by univariate and multivariate analyses to identify modifiable risk factors for these events.

resultsA total of 10,431 operations were for Crohn's disease (52.1%) or ulcerative colitis (47.9%), and 242 (2.3%) venous thromboembolic events occurred (178 deep vein thromboses, 46 pulmonary embolisms, 18 both) for a combined rate of 1.4% in Crohn's disease and 3.3% in ulcerative colitis. Deep vein thrombosis and pulmonary embolism each occurred at a mean of 10.8 days postoperatively (range for each, 0-30 days). A multivariate model found that bleeding disorder, steroid use, anesthesia time, emergency surgery, hematocrit <37%,malnutrition, and functional status were potentially modifiable risk factors that remained associated (p < 0.05) with venous thromboembolism on regression analysis. Patients with thromboembolism had longer length of stay (18.8 vs 8.9 days), more complications (41% vs 18%), and a higher risk of death (4% vs 0.9%). LIMITATIONS: This study was limited by its retrospective design and its limited generalizability to nonparticipating hospitals.

conclusionsInflammatory bowel disease patients are at increased risk for postoperative venous thromboembolism. Reducing preoperative anemia, steroid use, malnutrition, and anesthesia time may also reduce venous thromboembolism in this at-risk population. Risk-reducing, preventative strategies are needed in this at-risk population.