Subpleural continuous local anesthetic infusion as an opioid-sparing strategy after VATS lung resection: a prospective randomized controlled trial

Abstract

Thoracic surgery is associated with substantial postoperative pain, and opioid-based analgesia is often limited by adverse effects. This study evaluated whether subpleural continuous local anesthetic infusion (Sp-CLAI) using the On-Q system improves outcomes compared with intravenous patient-controlled analgesia (IV-PCA) after video-assisted thoracoscopic surgery (VATS) lung resection. In this prospective randomized trial, 180 patients undergoing elective multiport VATS were randomized to receive either ropivacaine-based On-Q infusion or fentanyl-based IV-PCA. After exclusions, 136 patients were analyzed. The primary endpoint was the postoperative pain trajectory over time, assessed using repeated-measures analysis of Numerical Rating Scale (NRS) scores. Secondary outcomes included opioid use, adverse events, and timepoint-specific pain differences. Longitudinal trends were assessed using repeated-measures ANOVA, and adjusted between-group differences at postoperative day (POD) 1, POD 3, and discharge were quantified using estimated marginal means. Early postoperative pain (PODs 1–3) was comparable between groups. The IV-PCA group had higher rates of nausea or vomiting ( P = 0.007), antiemetic use ( P = 0.004), rescue opioid use ( P < 0.001), and early discontinuation ( P = 0.015). At discharge, activity-related pain was lower in the On-Q group (adjusted difference, 0.52 NRS points; P = 0.038), although this did not reach the predefined minimal clinically important difference. Resting pain was similar. Opioid prescriptions at discharge were less frequent in the On-Q group (9 vs. 23; P = 0.002). Sp-CLAI using the On-Q system delivers analgesia equivalent to IV-PCA in the immediate postoperative period but provides superior activity-evoked pain control during recovery while substantially reducing opioid exposure and related side effects. These findings support Sp-CLAI using the On-Q system as a safe, effective, and opioid-sparing analgesic strategy that aligns with enhanced recovery after surgery (ERAS) principles and may facilitate early mobilization and functional recovery after VATS lung resection.