Postoperative Fever

Postoperative fever is defined as a temperature elevation greater than 101 °F. Fever is common in the postoperative period, occurring in up to 50% of patients; however, an infectious source is identified in less than half of febrile patients. The release of pyrogenic cytokines in response to the trauma of surgery may elicit a febrile response in the absence of infection. Early postoperative fevers (within 48h) are usually due to the inflammatory response to surgery and are not associated with infections. In contrast, fevers due to infection tend to occur later in the postoperative period. Risk factors for infectious causes include the presence of cancer, an immunosuppressed state, and anything that interrupts normal host defense mechanisms. These fevers tend to be higher (>101°F).