Perioperative Anesthetic Factors and Flap Outcome in Pediatric Head and Neck Free Flap Reconstruction: A...

Background: Microvascular free flap reconstruction is an established method for the management of complex head and neck defects in pediatric patients. However, the influence of perioperative anesthetic management on flap outcome in this population remains insufficiently defined. The aim of this study was to evaluate the association between selected perioperative anesthetic factors and flap outcome in pediatric patients. Methods: This retrospective observational study included pediatric patients undergoing microvascular free flap reconstruction between August 2011 and July 2020. Of 80 screened patients, 56 met the inclusion criteria based on complete medical records. Demographic, surgical, and perioperative anesthetic variables were collected. Continuous variables were compared using the Mann-Whitney U test, and categorical variables using the chi-squared test with Yates' correction. Correction for multiple testing was performed using the Benjamini-Hochberg false discovery rate procedure. Results: Complete flap survival was achieved in 50 patients (89.3%), while partial and total flap loss occurred in 3 patients each (5.4%). No significant associations with flap loss were identified for the type of anesthetic gas, opioid use, induction agents, intraoperative fluid therapy, diuresis, rocuronium dose, or operation time. Lower weight-adjusted doses of midazolam and propofol showed borderline unadjusted associations with flap loss; however, these differences did not reach statistical significance after correction for multiple testing. Patients with flap loss had a higher mean intraoperative body temperature compared to those with successful flap survival (36.65 °C vs. 36.05 °C; p < 0.05). Conclusions: In pediatric head and neck free flap reconstruction, most analyzed perioperative anesthetic factors were not associated with flap outcome. Dose-related findings for midazolam and propofol should be interpreted as exploratory and non-significant after correction for multiple testing, while higher intraoperative body temperature was associated with flap loss. However, these results are exploratory, cannot establish causality, and require confirmation in larger, preferably multicenter studies with adjustment for surgical and patient-related confounders.