Fever after varus derotational osteotomy is common, but not a risk factor for infection

Postoperative fever in pediatric patients following reconstructive hip surgery is of unknown significance. This study identifies the prevalence of postoperative fever after corrective hip surgery, its relationship to infection, and whether preventative use of anti-pyretics affects patient outcomes. Overall, 222 patients who underwent a varus derotational osteotomy (VDRO) between 11/1/2004 to 8/1/2014 with minimum 6 months follow up were retrospectively identified. Variables included diagnosis, inpatient stay, daily maximum temperature, duration of fever, fever workup, and administration of scheduled anti-pyretics. Fever was defined as temperature ≥38°C. In total, 123/222 (55.4%) and 70/222 (31.5%) had postoperative fevers of ≥38°C and ≥38.5°C, respectively. Average inpatient stay was 2.7 days postoperatively. Temperature (mean = 38.0°C) was greatest on postoperative day 1 (POD1), and 43.7% of patients had T ≥38°C on POD1. Anti-pyretics did not influence the duration of fever. Anti-pyretics on the day of surgery (POD0) did not influence the incidence of fever. Acetaminophen on POD0 significantly reduced likelihood of fever on POD1 (P = .02). Average length of fevers ≥38°C and 38.5°C were 8.4 and 4.2 hours, respectively. 3/18 (16.7%) fever workups administered were positive. Postoperative fever did not predict infection. 9/222 (4/1%) patients had postoperative infection - 5/123 (4.1%) with fever ≥38°C and 4/70 (5.7%) with fever ≥38.5°C. Rates of infection in patients with and without fevers were not significantly different (P = .97 for T ≥38°C and P = .38, for T ≥38.5°C). Though common, postoperative fever does not increase risk of infection. The low prevalence of positive cultures indicates routine fever workups can safely be avoided in most patients. Level of Evidence: III, retrospective comparative study