Preoperative and postoperative ultrasound guided intercostal nerve blockade on postoperative analgesia in patients undergoing video assisted thoracic surgery (VATS): a prospective randomized comparative study.

OBJECTIVES: Ultrasound-guided intercostal nerve block (ICNB) is an effective modality for alleviating pain after video-assisted thoracic surgery (VATS). However, the optimal timing for its administration remains controversial. This study aimed to compare the analgesic efficacy of preoperative versus postoperative ICNB in patients undergoing VATS. METHODS: A total of 172 adult patients undergoing VATS were randomized into two parallel groups: the pre-ICNB group (preoperative ultrasound-guided ICNB, n = 88) and the post-ICNB group (postoperative ultrasound-guided ICNB, n = 84). The primary outcome was the incidence of at least one episode of moderate-to-severe pain at rest (Numeric Rating Scale [NRS] score > 4) during the first 24 h postoperatively. Secondary outcomes included NRS scores during coughing, perioperative opioid consumption, sleep quality, and the incidence of postoperative complications. RESULTS: The incidence of moderate-to-severe resting pain during the first 24 h postoperatively was significantly lower in the post-ICNB group than in the pre-ICNB group (11.9% vs. 28.4%, P < 0.05). Both static (at rest) and dynamic (during coughing) NRS scores were significantly lower in the post-ICNB group at 4, 6 and 8 h postoperatively (P < 0.05); however, comparable pain scores were observed upon admission to the post-anesthesia care unit (PACU) and at 2, 24, and 48 h postoperatively (P > 0.05). Cumulative postoperative opioid consumption at 24 and 48 h was significantly lower in the post-ICNB group (P < 0.01). Furthermore, patients in the post-ICNB group exhibited superior sleep quality during the first two postoperative nights (P < 0.01). No significant differences were observed in total (intraoperative + postoperative) opioid consumption, overall recovery quality, or surgical/anesthetic complications. CONCLUSION: Postoperative ICNB provides superior early postoperative analgesia, reduces postoperative opioid requirements, and improves sleep quality compared with preoperative ICNB. These findings suggest that postoperative administration is a more effective strategy for acute pain management following VATS. CLINICAL TRIAL REGISTRATION: https://www.chictr.org.cn/showproj.aspx?proj=183278, identifier ChiCTR2300079183.