Duration of thrombosis prophylaxis in orthopaedic surgery.
BACKGROUND
We have given seven to 14 days thrombosis prophylaxis after orthopaedic surgery. Recently, six weeks prophylaxis has been recommended. We wished to evaluate the implications of prolonging prophylaxis.


METHODS
We made a very thorough search of the hospital register of diagnoses and the registers of the departments of radiology and nuclear medicine and determined the number of detected thromboembolic complications during a five and a half-year period.


RESULTS
We identified 91 cases (0.50%) with thromboembolism during the first six weeks after 18.368 orthopaedic operations: 1.4% after 836 total hip arthroplasties and 1.0% after 1.845 hip fractures. In these two groups 19 thromboembolic complications were registered after the second postoperative week. If it had been possible to prevent all of them by prolonging prophylaxis to six weeks, each avoided thromboembolism would have cost around US $ 23.700 in additional drug costs alone. One hip fracture patient died from probable thrombo-embolism during the second and one during the fourth postoperative week. No hip arthroplasty patients died from a probable thromboembolic complication during the third to sixth postoperative week.


CONCLUSIONS
We conclude that the frequency of clinically detectable thrombo-embolism and fatal pulmonary embolus is so low during the third to sixth postoperative weeks that prophylaxis beyond two weeks is unwarranted.
Finsen
V
V
Department of Orthopaedic Surgery, Trondheim University Hospital, Norway. vilh.finsen@medisin.ntnu.no
D000925:Anticoagulants / Q000627:therapeutic use*; D019644:Arthroplasty, Replacement, Hip; D004334:Drug Administration Schedule; D017984:Enoxaparin / Q000627:therapeutic use*; D006620:Hip Fractures / Q000601:surgery; D006801:Humans; D019637:Orthopedic Procedures; D011183:Postoperative Complications / Q000517:prevention & control*; D013923:Thromboembolism / Q000209:etiology / Q000517:prevention & control*
D000925:Anticoagulants; D017984:Enoxaparin