Abstract 324: Cancer, Arterial Thrombosis and Major Bleeding Following Orthopedic Surgery

Abstract

Background: Although cancer is a well-recognized risk factor for venous thromboembolic events, the relationship between cancer and perioperative arterial thrombotic and bleeding complications is uncertain. We therefore sought to investigate the incidence of thrombotic and bleeding events in subjects with and without a history of cancer undergoing orthopedic surgery. Methods: We performed a retrospective cohort analysis of 3,082 subjects > 21 years of age undergoing orthopedic surgery of the hip, knee, or spine between November 1, 2008 and December 31, 2009 at a tertiary care medical center. The presence of cancer was determined by ICD-9 diagnostic coding. In-hospital outcomes included perioperative myocardial necrosis (troponin > 99 th percentile), major bleeding (as per the International Society on Thrombosis and Haemostasis [ISTH] perioperative bleeding definition), and coded myocardial infarction (MI) and post-operative hemorrhage using the hospital administrative dataset using ICD-9 procedure codes. Results: Of the 3,082 subjects, 69 (2.2%) were identified as having a history of cancer. Subjects with cancer were older (65.5±14.7 vs 60.6±13.2, P=0.003) and less likely female (32/69 [46%] vs 1790/3013 [59%], P=0.03). Subjects with cancer had a greater incidence of myocardial necrosis (15/69 [21.7%] vs 164/3013 [5.4%], P<0.001), MI (3/69 [4.3%] vs 17/3013 [0.6%], P<0.001), perioperative major bleeding (21/69 [30.4%] vs 144/3013 [4.8%], P<0.001), and post-operative hemorrhage (6/69 [8.7%] vs 20/3013 [0.7%], P<0.001) than subjects without cancer. Following multivariable logistic regression, cancer was associated with myocardial necrosis (OR 2.64, 95% CI 1.30-5.35, P=0.007), MI (OR 2.65, 95% CI 0.63-11.09, P=0.18), major bleeding, (OR 6.45, 95% CI 3.42-12.17, P<0.001), and post-operative hemorrhage (OR 7.64, 95% CI 2.44-23.93, P<0.001). Conclusions: There is an increased risk of both thrombotic and bleeding complications in subjects with cancer in the setting of orthopedic surgery. This perioperative risk deserves careful attention in preoperative clearance and future studies aimed at attenuating this increased risk are warranted.