Are Revision Hip Arthroplasty Patients at Higher Risk for Venous Thromboembolic Events Than Primary Hip Arthroplasty Patients?

Background: The purpose of this study is to determine whether revision total hip arthroplasty (THA) is associated with increased rates of deep vein thrombosis (DVT) and pulmonary embolism (PE) when compared to primary THA. Methods: We queried the American College of Surgeons National Surgical Quality Improvement Program database for all primary and revision THA cases from 2011 to 2014. Demographic data, medical comorbidities, and venous thromboembolic rates within 30 days of surgery were compared between the primary and revision THA groups. Results: Revision THA had a higher rate of DVT than the primary THA (0.6% vs 0.4%, P = .016), but there was no difference in the rate of PE (0.3% vs 0.2%, P = .116). When controlling for confounding variables, revision surgery alone was not a risk factor for DVT (odds ratio 0.833, 95% confidence interval 0.564-1.232) or PE (odds ratio 1.009, 95% confidence interval 0.630-1.616). Independent risk factors for DVT include age >70 years, malnutrition, infection, operating time >3 hours, general anesthesia, American Society of Anesthesiologists classification 4 or greater, and kidney disease (all P < .05). Probability of DVT ranged from 0.2% with zero risk factors to 10% with all risk factors. Independent risk factors for PE included age >70 years, African American ethnicity, and operating time >3 hours (all P < .05) with probabilities of PE postoperatively ranging from 0.2% to 1.1% with all risk factors. Conclusion: Revision surgery alone is not a risk factor for venous thromboembolism after hip arthroplasty. Surgeons should weigh the risks and benefits of more aggressive anticoagulation in certain highrisk patients. (C) 2017 Elsevier Inc. All rights reserved.