A863. TIMING OF SYMPTOMATIC PULMONARY EMBOLI FOLLOWING TOTAL HIP AND TOTAL KNEE ARTHROPLASTY. ARE WE AIMING AT THE WRONG TARGET?

Abstract

The focus of deep vein thrombosis (DVT) prophylaxis following total joint arthroplasty has shifted in recent years to the reduction of symptomatic pulmonary emboli (PE). The relative infrequency and presumed delayed occurrence of these events has led many to suggest that the risks of more frequent early postoperative complications of treatment, especially bleeding, be weighed against the benefits of thromboembolic prophylaxis. The purpose of this study was to determine the timing and risk factors associated with the development of symptomatic PE following total hip arthroplasty (THA) and total knee arthroplasty (TKA).

A retrospective analysis was performed of all patients diagnosed with a symptomatic pulmonary embolism following THA and TKA performed from January, 2004 to March, 2008. The records of 4706 patients were reviewed who were operated upon by 7 surgeons, and a total of 58 PE were identified. All patients were managed and treated by an anti-coagulation dosing service. Helical CT Scans were used to make the diagnosis of PE.

The overall incidence of PE was 1.2%, with 1.8% occurring in TKAs and 0.5% occurring in THAs. 48 of the 58 PE patients (83%) were women. 33 patients (57%) had unilateral TKA, 14 (24%) had bilateral TKA and 11 (19%) had THA. The average patient age was 65 (range: 44–88) and BMI was 33.8 (range: 24.7–51.9). There was no apparent correlation between age and BMI with incidence of PE. The PE were diagnosed an average of 4 days (range: 1–46) following surgery. 56 of the 58 patients (97%) were diagnosed by the sixth postoperative day. The average INR at the time of diagnosis was 1.7 (range: 1.0–3.0). There were two mortalities (3%), both of which occurred within the first two postoperative days.

The PE in this study occurred predominantly in women undergoing TKA. There appears to be an urgent need to develop an effective prophylaxis program aimed at preventing PE in the early post-operative period and to identify patients at risk of these PE.