Ultrasound-guided Serratus Anterior Plane Block Versus Thoracic Paravertebral Block on Alleviating the Acute and Chronic Pain Following the Video-assisted Thoracic Surgery: a Prospective, Randomized, Double-blinded Non-inferiority Clinical Trial

Background: The anesthetic efficacy of ultrasound-guided serrate anterior plane block (SAPB) on alleviating postoperative acute and chronic pain has been well concerned. The present study aims to compare the efficacy between ultrasound-guided SAPB and thoracic paravertebral block (PVB) on alleviating both acute pain and chronic pain following the video-assisted thoracic surgery. Methods: It was a prospective, randomized, double-blinded non-inferiority clinical trial involving 99 patients with lung nodules receiving video-assisted thoracic surgery with ultrasound-guided SAPB (SAPB group) or PVB (PVB group) on T4 and T7 vertebra using 0.375% ropivacaine at 2 mg/kg. The Visual Analogue Scale (VAS) scores at both rest and cough at 24 h postoperatively were graded as the primary outcome. Besides, secondary outcomes included the incidence of chronic pain at 3 and 6 months postoperatively, VAS scores at rest and cough at 1, 6, 12 and 48 h postoperatively, consumptions of fentanyl and remifentanyl, and the pressing times of the patient-controlled analgesia (PCA) pump. Baseline characteristics, surgery characteristics and primary and secondary outcomes between groups were compared. Results: A total of 92 eligible patients were recruited, including 46 in SAPB group and 46 in PVB group. Baseline and surgery characteristics between groups were comparable (all P>0.05). No significant differences in VAS scores at rest and cough at 1 h, 6 h, 12 h, 24 h, 48 h, 3 months and 6 months postoperatively between SAPB group and PVB group were detected (all P>0.05). Conclusion: The anesthetic efficacy of ultrasound-guided SAPB was not inferior to PVB on alleviating postoperative acute and chronic pain following the video-assisted thoracic surgery.Trial registration number: retrospective registered in the Chinese Clinical Trial Registry (ChiCTR2100050991, http://www.chictr.org.cn, 09/09/2021, Yan Wang, MD).