Thrombosis prophylaxis using external compression

Abstract

Seventy-seven surgical patients considered to be at high risk were randomized and stratified to receive either long leg TED hose or sequential compression devices applied in the operating room and continued for at least 72 hours post-operatively. All patients were monitored with Doppler, impedance and 125I fibrinogen leg scanning. Pulmonary angiography or venography, or both, were done when dictated by the clinical signs and symptoms. Serial coagulation tests were done preoperatively and postoperatively. Fibrinogen scans were abnormal in 10.2 per cent of the patients in the TED group and in 2.6 per cent of those in the SCD group. One patient in the SCD group, 2.6 per cent, and one patient in the TED group, 2.5 per cent, had nonfatal pulmonary emboli confirmed by angiography. Scans of the leg in both of these patients were normal. A control group was made up of 96 surgical patients considered to be at high risk who refused the protocol. Retrospective analysis of these 96 such patients yielded a 20.8 per cent scan incidence of thrombi. No fatalities occurred in any of the study group of patients, but one death due to pulmonary embolus occurred in the control group. The over-all incidence of positive fibrinogen scans were 6.5 per cent in the study group and 21.9 per cent in the control group. A statistically significant increase in fibrinolytic activity was seen in the orthopedic-neurologic subset of SCD treated individuals only. We conclude that a statistically significant reduction in the fibrinogen scan incidence of thrombosis is observed when the SCD and TED are used as compared with the control group. Long leg TED hose alone provide an intermediate measure of prophylaxis in surgical patients considered to be at high risk. However, the combination of TED hose preoperatively followed by SCD postoperatively for a minimum of 72 hours provides excellent prophylaxis in the surgical patients considered to be at high risk. The subgroup differences in fibrinolytic activity are unexplained but stress the importance of analyzing hematologic-coagulation measurements in light of the type of surgical procedure performed.