Serratus anterior plane block or thoracic paravertebral block for postoperative pain treatment after uniportal video-assisted thoracoscopic surgery: a retrospective propensity-matched study

BACKGROUND: Reports of postoperative pain treatment after uniportal video-assisted thoracoscopic surgery are limited. Thoracic paravertebral block and serratus anterior plane block have been described recently in pain management after thoracic surgery. A comparison between these two blocks for postoperative analgesia after uniportal video-assisted thoracoscopic surgery has not been previously reported. The aim of this study was to compare the analgesic benefits of serratus plane block and thoracic paravertebral block after uniportal video-assisted thoracoscopic surgery and examined the two block types for noninferiority. METHODS: From December 2015 to May 2018, a total of 636 relevant records of patients who underwent uniportal video-assisted thoracoscopic surgery under general anaesthesia alone or with the addition of serratus plane block or thoracic paravertebral block performed preoperatively were identified. A propensity-matched analysis incorporating preoperative variables was used to compare the efficacy of postoperative analgesia in three groups. RESULTS: Overall, 123 patients were identified for analysis. Propensity score matching resulted in 41 patients in each group. The visual analogue scale scores were significantly lower in the serratus plane block group and the thoracic paravertebral block group than in the control group at the 1st, 2nd, 4th, and 6th postoperative hours. Cumulative opioid consumption was significantly lower in the serratus plane and thoracic paravertebral block groups than in the control group at 6 hrs (18.3±3.1 mg, 18.7±3.9 mg vs 21.5±4.4 mg; P=0.001) and 24 hrs (43.4±7.3 mg, 42.5±7.7 mg vs 49.3±8.8 mg; P<0.001) postoperatively. The serratus plane block group was noninferior to the thoracic paravertebral block group on pain score and opioid consumption. CONCLUSION: The addition of single-injection serratus plane or thoracic paravertebral block is associated with early analgesic benefits in patients undergoing uniportal video-assisted thoracoscopic surgery, including a reduction in the postoperative opioid consumption and pain scores. Serratus plane block is as effective as thoracic paravertebral block for reducing postoperative pain.