Ultrasound-guided nerve block anesthesia improves perioperative pain in patients undergoing free flap reconstruction for head-and-neck tumor: a randomized, controlled trial.

Objective: The study attempted to explore the postoperative pain control of ultrasound-guided iliac fascia and trigeminus block anesthesia among patients undergoing free flap reconstruction for head-and-neck tumors.

Methods: This research implemented a prospective, double-blinded, randomized, and placebo-controlled clinical trial. Patients between 18 and 85 years who had accepted a radical head-and-neck tumor resection while simultaneously undergoing the vascularized anterolateral femoral free flap reconstruction for the surgical coloboma were recruited. The subjects were randomly divided into nerve block and blank groups. Faciocervical pain while speaking was the primary outcome variable. It was measured using the visual analog scale (VAS) during the perioperative period up to postoperative 7 days. Descriptive statistics and logistic regression analysis were performed. The data were analyzed using the Mann-Whitney U test, linear mixed-effects model, chi-square test, and Fisher's exact test. The statistically significant level was set at P < 0.05.

Results: The sample comprised 145 subjects with a mean age of 58.4 (SD = 12.7), 102 (70.3%) males. There were 71 (49.0%) and 74 (51.0%) participants in the nerve block and blank groups. Nerve block anesthesia reduced postoperative pain, depicted by VASS (0.99 ± 1.72 P < 0.0001). The out-of-bed mobilization started before within the nerve block group (47.45 ± 19.68 P = 0.017). The high expression of IL-6 could decrease the efficacy of this protocol (P = 0.0176).

Conclusion: Ultrasound-guided iliac fascia combined with trigeminus block anesthesia is an effective method for pain management in patients who underwent head-and-neck tumor surgery in conjunction with the simultaneous repair using the vascularized anterolateral femoral free flap.

Trial registration: The Institutional Ethics Review Board approved the study and retrospectively registered it with the Chinese Clinical Trial Registry at January 10, 2024 (ChiCTR2400079720).