Higher altitude leads to increased risk of venous thromboembolism after acetabular and pelvic ring injury

Abstract

IntroductionThere is a high post-operative incidence of venous thromboembolisms (VTEs), specifically deep vein thrombosis (DVT) and pulmonary embolism (PE), in pelvic ring and acetabular fractures, and identification of risk factors for VTEs is crucial to decrease this highly morbid complication. High altitudes have a known physiological effect on the body that may predispose patients to developing VTEs in the postoperative period. The purpose of this study was to investigate the relationship between pelvic ring and acetabular fractures occurring at high altitudes and the development of postoperative VTEs. MethodsIn this retrospective study, the Truven MarketScan claims database was used to identify patients who underwent surgical fixation of a pelvic ring and/or acetabular fracture from January 2009 to December 2018 using Current Procedural Terminology (CPT) codes. Patient characteristics, including medical comorbidities, were collected. The zip codes of where the surgeries took place were used to determine recovery altitude and patients were separated into either the high altitude (>4000 feet) or low altitude (<100 feet) cohorts. Chi-squared and multivariate analyses were performed to investigate the association between altitude and the development of VTE postoperatively. ResultsIn total, 68,923 patients were included for analysis. At 30-days postoperatively, a higher altitude was associated with increased odds of developing a PE (OR 1.47, p = 0.019). At 90-days postoperatively, a higher altitude was associated with increased odds of DVT (OR 1.24, p = 0.029) and PE (OR 1.63, p < 0.001). ConclusionSurgical fixation of pelvic ring and acetabular fractures performed at a higher altitude (>4,000feet) are associated with increased odds of developing a PE in the first 30 days as well as developing a DVT or PE at 90 days postoperatively. Future prospective studies are needed to further elucidate the causality of altitude on the development of postoperative VTEs.