Analysis of postoperative venous thromboembolism in patients with chronic ulcerative colitis: Is it the disease or the operation?

BACKGROUND: Patients with IBD have a higher baseline risk of venous thromboembolism, which further increases with surgery. Therefore, extended venous thromboembolism chemoprophylaxis has been suggested in certain high-risk cohorts. OBJECTIVE: The purpose of this study was to determine whether the underlying diagnosis, operative procedure, or both influence the incidence of postoperative venous thromboembolism. DESIGN: This was a retrospective review. SETTINGS: The American College of Surgeons-National Surgical Quality Improvement Project database was analyzed. PATIENTS: The NSQIP database was queried for patients with chronic ulcerative colitis and non-IBD undergoing colorectal resections using surgical Current Procedural Terminology codes modeled after the 3 stages used for the surgical management of chronic ulcerative colitis from 2005 to 2013. MAIN OUTCOME MEASURES: We measured 30-day postoperative venous thromboembolism risk in patients with chronic ulcerative colitis based on operative stage and risk factors for development of venous thromboembolism. RESULTS: A total of 18,833 patients met inclusion criteria, with an overall rate of venous thromboembolism of 3.8. Among procedure risk groups, venous thromboembolism rates were high risk, 4.4%; intermediate risk, 1.6%; and low risk, 0.7% (across risk groups, p < 0.01). Emergent case subjects exhibited a higher rate of venous thromboembolism than their elective counterparts (6.9% vs 3.1%). Factors significantly associated with venous thromboembolism on adjusted analysis included emergent risk case (adjusted OR = 7.85), high-risk elective case (adjusted OR = 5.07), intermediate-risk elective case (adjusted OR = 2.69), steroid use (adjusted OR = 1.54), and preoperative albumin <3.5 g/dL (adjusted OR = 1.45). LIMITATIONS: Because of its retrospective nature, correlation between procedures and venous thromboembolism risk can be demonstrated, but causation cannot be proven. In addition, data on inpatient and extended venous thromboembolism prophylaxis use are not available. CONCLUSIONS: Emergent status and operative procedure are the 2 highest risk factors for postoperative venous thromboembolism. Extended venous thromboembolism prophylaxis might be appropriate for patients undergoing these high-risk procedures or any emergent colorectal procedures.