INCIDENCE OF FATAL PULMONARY-EMBOLISM AFTER 1,390 KNEE ARTHROPLASTIESWITHOUT ROUTINE PROPHYLACTIC ANTICOAGULATION, EXCEPT IN HIGH-RISK CASES

A consecutive series of 1,390 primary total knee arthroplasty (TKA) pr ocedures (1,201 patients, 1,600 arthroplasties) performed between Janu ary 1980 and July 1994 were reviewed to establish the incidence of dea th from pulmonary embolism (PE). Nine hundred twenty-three bi- or tric ompartment TKAs and 467 unicompartment TKAs were performed as one-stag e procedures. Chemical thromboprophylaxis was used only in high-risk c ases in which there was a history of previous thromboembolism or obesi ty. There were no deaths from PE after unicompartment arthroplasty pro cedures. Autopsy confirmed PE as the cause of death in 2 patients foll owing bi-and tricompartment TKAs (0.22%; 95% confidence interval [CI], 0.03-0.8%). The incidence was higher for one-stage bilateral TKA as 1 of the autopsy-confirmed deaths occurred in this group 0.7% (95% CI, 0.02-3.78%). Two other deaths were certified without postmortem examin ation (pneumonia and myocardial infarction in each case). As PE could not be ruled out as the cause of death in the latter 2 cases, these we re considered as possible PE deaths to provide the maximum possible de ath rate that could result. Thus, the maximum possible incidence of fa tal PE after TKA without routine use of chemical anticoagulation was 0 .4% (95% CI, 0.1-1.1%). It is concluded that the risk of fatal PE afte r unilateral TKA and unicompartment knee arthroplasty is low. The risk of clinical, nonfatal thromboembolic events, which might themselves w arrant prophylaxis, was not quantified in this article.