Literature suggests that intravenous prophylaxis exceeding 48 h offers no additional benefit in preventing surgical site infections (SSI) in patients with microvascular head and neck reconstruction. However, protocols for antibiotic therapy duration post-reconstruction are not standardized. This study identifies factors predicting prolonged intravenous antibiotic use and antibiotic escalation in patients receiving free flap head neck reconstruction.

A retrospective analysis of 446 patients receiving free flap reconstruction was conducted, examining predictors for antibiotic therapy > 10 days and postoperative escalation. 111 patients (24.8%) experienced escalation, while 159 patients (35.6%) received prolonged therapy. Multivariate regression analysis revealed predictors for escalation: microvascular bone reconstruction (p = 0.008, OR = 2.0), clinically suspected SSI (p < 0.001, OR = 5.4), culture-positive SSI (p = 0.03, OR = 2.9), extended ICU stay (p = 0.01, OR = 1.1) and hospital-acquired pneumonia (p = 0.01, OR = 5.9). Prolonged therapy was associated with bone reconstruction (p = 0.06, OR = 2.0), preoperative irradiation (p = 0.001, OR = 1.9) and culture-positive SSI (p < 0.001, OR = 3.5).

The study concludes that SSIs are a primary factor driving the escalation of perioperative antibiotic use. Clinical suspicion of infection often necessitates escalation, even in the absence of confirmed microbiological evidence. Microvascular bone reconstruction was a significant predictor for both the escalation and extension of antibiotic therapy beyond 10 days. Furthermore, preoperative radiation therapy, hospital-acquired pneumonia, and prolonged ICU stay were associated with an increased likelihood of escalation, resulting in significantly extended antibiotic administration during hospitalization. Antibiotic stewardship programmes must be implemented to reduce postoperative antibiotic administration time.

Trial registration The study was registered approved by the local Ethics Committee (Nr: 18-1131-104).