Anticoagulation in Elective Spine Cases: Rates of Hematomas Versus Thromboembolic Disease

STUDY DESIGN: Retrospective cohort study with propensity matched cohorts. OBJECTIVE: The purpose of this study was to evaluate the association of anticoagulation with VTE and hematoma complications after spine surgery. SUMMARY OF BACKGROUND DATA: One of the major complications of surgery is VTE which can range in presentation. Spine surgery is an especially complex balance between minimizing the risk of a VTE event and also the increased risk of a hematoma which can lead to devastating neurological outcomes. METHODS: The elective spine surgery cases at a single academic center between 2015 and 2017 were identified. A total of 3790 patients were initially identified. Two hundred sixty patients were excluded. The cohort was then matched using a propensity score. This matched a single patient who did not receive anticoagulation to a single patient who did within the institution. This left a total of 1776 patients with 888 patients in each arm. RESULTS: The incidence of VTE, PE, and unplanned reoperation for hematoma in this cohort was 0.96%, 0.34%, and 1.13%, respectively. Predicted odds of VTE and PE were not significantly different; however, the odds of an unplanned reoperation for hematoma (odds ratio [OR] = 7.535, 95% confidence interval [CI]: 2.004-28.340, P = 0.002) were greater for those who received pharmacological anticoagulation in our institutional cohort. CONCLUSION: In this study, anticoagulation does not lead to lower rates of VTE events, but it increases the risk of symptomatic hematomas which require a return trip to the OR. While this was not a randomized controlled trial, we attempted to correct for this with propensity matching. Future randomized control trials would be needed.Level of Evidence: 3.