Fat embolism and respiratory distress associated with cemented femoral arthroplasty.

Embolization of fat and marrow contents results from increased intramedullary pressure generated during insertion of an intramedullary implant such as a total hip prosthesis or an intramedullary nail. Embolization is accentuated when the implants are inserted using cemented techniques. These embolic events, observed by transesophageal echocardiography, correlate with hemodynamic changes suggesting pulmonary embolism. The ability of patients to tolerate these cardiopulmonary changes depends on both baseline pulmonary function and quantity of embolic debris delivered to the pulmonary vasculature during the operation. Patients with good pulmonary function can tolerate the embolic load associated with implantation of a cemented implant and will demonstrate little cardiopulmonary compromise. Patients with poor pulmonary reserve may be unable to withstand the showering of debris resulting from this procedure and are at risk for hypoxia, cardiopulmonary dysfunction, and possibly death. Measures to remove marrow contents and reduce intramedullary pressure during cemented femoral arthroplasty or to switch to an uncemented technique may minimize the cardiopulmonary risk incurred by this group of patients.