Impact of anesthesia modality and mechanical venous thromboembolism prophylaxis on the incidence of symptomatic deep venous thrombosis after TKA

Abstract

BackgroundVenous thromboembolic events (VTE) are a common complication of total knee arthroplasty (TKA). Prior studies have discussed the utility of mechanical VTE prophylaxis as a monotherapy for low-risk TKA patients. We assess the incidence of clinically significant deep venous thrombosis (DVT) or pulmonary embolism (PE) in low-risk TKA patients who receive mechanical VTE prophylaxis and undergo spinal, epidural, or general anesthesia for their surgery. MethodsA retrospective study was performed on consecutive low-risk patients who received a TKA between July 2002 and June 2015 with spinal anesthesia (n=65), epidural and general anesthesia (n=154), or general anesthesia alone (n=152). Patients with spinal anesthesia had mechanical VTE prophylaxis until 15h postoperatively, when remobilization was permitted. Patients who received epidural or general anesthesia had mechanical VTE prophylaxis for 2h postoperatively. Notable outcomes included development of clinically symptomatic DVT or PE, patient demographics, and perioperative lab values. Statistical analysis was performed using SPSS 22, with chi-squared and Fisher's exact tests for categorical variables and the Kruskal–Wallis test with Scheffe's method for continuous variables. ResultsNo clinically symptomatic DVT or PE was diagnosed. Patient demographics were equivocal. A statistically significant decrease in prothrombin and activated partial thromboplastin times were noted in the general anesthesia group, but all measurements were within the normal range. ConclusionsA short course of mechanical VTE prophylaxis may be appropriate for low-risk patients who can immediately mobilize.