[Postoperative fever in orthopedic and urologic surgery].

Post-operative fever incidence varies widely. In clean and clean-contaminated surgery the non-infectious fever is more frequent than the infectious fever. We performed a prospective study including 303 patients who underwent orthopedic and urologic elective surgery. The aims of our study were to investigate the incidence of post-operative fever, its etiology, the relationship between time of onset and the etiology, and the usefulness of extensive fever work-up to determine post-operative infection. The incidence of post-operative fever was 14% (42/303) of which 81% (34/42) was noninfectious and 19% (8/42) was infectious. The etiology of the fever in the first 48 hours after surgery was always non-infectious (p < 0.001). An extensive fever work-up was performed in patients who presented fever only after the initial 48 hours of surgery with normal physical examination (n = 19) consisting of chest x-ray, blood (2) and urine cultures. The chest x-ray was normal in all the patients, the urine cultures were positive in four cases (21%, IC 95%: 6-45) and the blood cultures in only one case (5%, IC 95%: 0.1-26). Seven patients had post-operative infections without fever as a clinical sign. The most frequently observed etiology of post-operative fever was non-infectious, related to the normal inflammatory host response to surgery. Based on the present results, the extensive fever work-up performed to investigate post-operative infection does not seem to be a useful tool. The diagnosis of post-operative infection was based on clinical follow up and the correct interpretation of the patient's symptoms and signs.