Bilateral Sphenopalatine Ganglion Blocks in Adult Tonsillectomy and Uvulopalatopharyngoplasty: A Matched Retrospective Cohort Study

Introduction: Tonsillectomy with adenoidectomy (T&A) and modified uvulopalatopharyngoplasty (UPPP) are associated with significant postoperative pain. Preoperative sphenopalatine ganglion (SPG) blocks reduce postoperative pain and opioid use in pediatric populations, but adult data are limited. This study evaluates the efficacy of SPG blocks in reducing postoperative pain and opioid use in adults undergoing sleep surgery.

Methods: A retrospective single-institution matched cohort study compared patients treated with bilateral SPG blocks versus controls undergoing UPPP, T&A, or tonsillectomy alone (T) (2021-2025). Patients were matched 1:1 for age, sex, race, body mass index (BMI), Charlson comorbidity index (CCI), and procedure type. Patients with chronic pain or neuropathy, or preexisting opioid prescriptions, were excluded. Primary outcomes included postoperative analgesic use, post-anesthesia care unit (PACU) pain scores, postoperative nausea and vomiting (PONV) scores.

Results: Twenty-four patients, 12 matched pairs (mean age 44.6±16.8 years, BMI 31.4±7.7, 75% male) were analyzed. Procedures included UPPP (70.8%), T&A (25%), and T (4.2%). There were no block-associated adverse events. SPG block patients trended toward higher non-opioid analgesic use including acetaminophen (p=0.12), celecoxib (p=0.17), and gabapentin (p=0.10). There was no significant difference in hydromorphone, fentanyl, oxycodone, or morphine requirements between groups. PACU pain and PONV scores were comparable. Notably, following discharge, fewer SPG block patients contacted the office due to pain (2 vs. 6 patients) and fewer required opioid refills (1 vs. 4 patients).

Conclusions: SPG blocks in adults undergoing sleep surgery were safe and associated with trends toward increased non-opioid analgesic use. While immediate PACU pain scores did not differ, fewer block patients reported uncontrolled postoperative pain and/or required opioid refills after discharge, suggesting that SPG blocks may provide longer-lasting benefit beyond the immediate postoperative period.