Prophylaxis Against Venous Thromboembolic Disease in Patients Having a Total Hip or Knee Arthroplasty

Patients undergoing total joint replacement are particularly prone to thromboembolic complications with potentially life-threatening consequences1-3. Charnley et al., in a series of 7959 total hip replacements performed between 1962 and 1973, reported that the prevalence of nonfatal pulmonary embolism was 7.89% and that the prevalence of fatal pulmonary embolism was 1.04%4,5. Similarly, in 1974, Coventry et al.6 identified an overall prevalence of pulmonary embolism of 2.2% in a series of 2012 consecutive total hip replacements; in a subset of patients who had received no prophylactic anticoagulation, the prevalence of fatal pulmonary embolism was 3.4%. However, the average duration of the operation was 2.4 hours, the average total blood loss was 1650 mL, and the average amount of blood transfused was 1144 mL. Prophylactic anticoagulation with warfarin was started five days after the operation. On the average, patients were managed with bed rest for one week prior to walking and were discharged three weeks after the operation6. The prevalence of deep venous thrombosis after total knee arthroplasty is greater than that after total hip arthroplasty. Deep-vein thrombosis is far more refractory to available means of prophylaxis but since the prevalence is greater in the distal part of the limb, symptomatic and fatal pulmonary emboli are far less common. Moreover, it is essential to recognize that thromboembolic disease is manifested clinically as two very different conditions after hip and knee arthroplasty7,8.