Venous thromboembolism following primary total hip arthroplasty

In the absence of thromboprophylaxis, venographically detected deep vein thrombosis (DVT) occurs in approximately 50% of patients undergoing primary total hip arthroplasty. Despite the existence of national and international guidelines, thromboprophylaxis may be underused.

A retrospective review was performed of the clinical incidence of venous thromboembolism (VTE) and thromboprophylactic practice patterns over a nine year period. Patient baseline characteristics, VTE risk factors, prophylactic modalities (mechanical and pharmacological), operation duration, type of prosthesis and fixation, mode of anesthesia, hospital length of stay (LOS) were analyzed. The main efficacy outcome was DVT and/or pulmonary embolism (PE). The primary safety outcome was major bleeding.

In-hospital incidence of VTE was 2.5% and 3.8% up to three months post hospital discharge. Median time to postoperative VTE development in-hospital and after discharge was 6.5 days (IQR: 5.0 to 8.0 days) and 29.0 days (IQR: 19.5 to 38.0 days) respectively. 66.7% (95% CI: 30.0 to 90.3%) of all readmissions for VTE occurred within one month post-operatively. There were no readmissions for VTE in patients discharged on extended pharmacological prophylaxis.

The use of prophylactic protocols was associated with relatively low VTE rates up to three months with minimal bleeding complications. A more intense in-hospital and extended prophylaxis beyond hospitalization is recommended in this high risk group of patients.