Intercostal Nerve Block for Bilateral Thoracoscopic Sympathectomy: A Prospective Observational Cohort Comparison of Three Analgesic Protocols

Background/Objectives: Bilateral thoracoscopic sympathectomy (BTS) is the definitive treatment for primary focal hyperhidrosis, yet postoperative pain remains an undertreated consequence with no established analgesic consensus. This study compared three analgesic regimens on pain trajectory, opioid consumption, and functional recovery following BTS. Methods: In this prospective observational cohort study, 300 patients undergoing BTS were allocated in a non-randomized manner reflecting institutional practice to three parallel cohorts (n = 100 each): Group 1 received systemic opioids alone; Group 2 received opioids plus pre-emptive local anesthetic wound infiltration; and Group 3 received opioids plus thoracoscopic-guided intercostal nerve block (ICNB). Primary outcomes included pain intensity on the Numerical Rating Scale and total opioid consumption. Results: ICNB patients reported significantly lower mean peak pain scores (3.8 ± 1.7) versus local infiltration (4.6 ± 1.9) and opioid-only groups (5.2 ± 2.1; p < 0.001). Total opioid consumption was reduced by 38% in the ICNB group (12.4 ± 4.8 mg vs. 20.1 ± 6.3 mg; p < 0.001). Moderate-to-severe pain occurred in 42.0% of ICNB patients versus 74.0% of controls (p < 0.001). ICNB was independently associated with reduced moderate-to-severe pain (adjusted odds ratio (AOR) 0.31; 95% confidence interval (CI) 0.17–0.56; p < 0.001). ICNB patients returned to normal activities faster (median 3 vs. 5 days; p = 0.008) with higher satisfaction (91.0% vs. 78.0%; p = 0.044). Conclusions: In this observational cohort, ICNB was associated with significantly lower postoperative pain scores, reduced opioid consumption, and faster functional recovery following BTS. These findings suggest that ICNB may be an effective adjunct analgesic strategy for ambulatory BTS, pending confirmation in randomized controlled trials.