Fatal fat embolism during cemented total knee arthroplasty: a case report.

Evidence is accumulating that embolization of bone marrow contents to the lungs can cause the hypotension, hypoxemia, cardiac arrest and death reported after total hip arthroplasty and that the embolism results from high intramedullary pressures exerted during implantation of the prosthesis. The authors describe such an occurrence in an 80-year-old man who had a cemented long-stem total knee prosthesis inserted. Autopsy revealed numerous pulmonary fat emboli that were distributed predominantly in arterioles and capillaries. The possibility of pulmonary fat microembolism occurring during cemented total knee arthroplasty should be recognized, particularly when prostheses with long intramedullary stems are used. Preventive or prophylactic measures that should be considered to avoid fat embolism during implantation include venting the intramedullary canal and meticulous lavage to clear away intramedullary debris. Increasing the inspired oxygen concentration as the prosthesis is inserted and monitoring of cardiopulmonary status to avoid simultaneous hypotension and hypoxemia may help to prevent the cardiopulmonary changes associated with pulmonary fat microembolism.