Association between Antibiotic Redosing Prior to Incision and Risk of Incisional Site Infection in Children with Appendicitis.

OBJECTIVE: To evaluate whether redosing antibiotics within an hour of incision is associated with a reduction in incisional surgical site infection (iSSI) in children with appendicitis.

SUMMARY OF BACKGROUND DATA: Existing data remain conflicting as to whether children with appendicitis receiving antibiotics at diagnosis benefit from antibiotic redosing prior to incision.

METHODS: This was a multicenter retrospective cohort study using data from the Pediatric National Surgical Quality Improvement Program augmented with antibiotic utilization and operative report data obtained though supplemental chart review. Children undergoing appendectomy at 14 hospitals participating in the Eastern Pediatric Surgery Network from 7/2016-6/2020 who received antibiotics upon diagnosis of appendicitis between 1-6 hours prior to incision were included. Multivariable logistic regression was used to compare odds of iSSI in those who were and were not redosed with antibiotics within one hour of incision, adjusting for patient demographics, disease severity, antibiotic agents, and hospital-level clustering of events.

RESULTS: 3,533 children from 14 hospitals were included. Overall, 46.5% were redosed (hospital range: 1.8%-94.4%, P<0.001) and iSSI rates were similar between groups (redosed: 1.2% vs. non-redosed: 1.3%; OR 0.84, [95%CI 0.39-1.83]). In subgroup analyses, redosing was associated with lower iSSI rates when cefoxitin was used as the initial antibiotic (redosed: 1.0% vs. non-redosed: 2.5%; OR 0.38, [95%CI 0.17-0.84]), but no benefit was found with other antibiotic regimens, longer periods between initial antibiotic administration and incision, or with increased disease severity.

CONCLUSIONS: Redosing of antibiotics within one hour of incision in children who received their initial dose within 6 hours of incision was not associated with reduction in risk of incisional site infection unless cefoxitin was used as the initial antibiotic.