Fat embolism and autologous blood transfusions in orthopaedic surgery

Abstract

Fat embolism is a well-known complication associated with orthopaedic procedures like total hip or knee arthroplasty. The clinical relevance of fat embolism in association with orthopaedic procedures is, however, controversial. Although transesophageal echocardiography indicates echogenic material in the central circulation in more than 90% of patients undergoing cemented hip arthroplasty, the incidence of cardiac arrest due to pulmonary fat embolism is less than 1%. Cementation is known to increase the incidence of embolic complications. The duration of the pressure and the intensity of pressure inside the bone cavity are correlated with the incidence of fat emboli and the cardiopulmonary function. The use of modern cementing techniques and non-cemented arthroplasty reduces the incidence and the clinical risk of fat embolism. The disadvantages with allogeneic blood transfusions have encouraged the development of methods to reduce the need for such transfusions. Devices for salvage of blood during or after orthopaedic procedures have been shown to reduce the need for allogeneic transfusions. Shed blood may contain high concentrations of inflammatory mediators and may be contaminated with fat particles which may increase the risk of fat embolism. Transfusion of blood after washing and centrifugation and filtration of salvaged blood are available methods for transfusion of shed blood and that may reduce the amount of transfusion of fat.