Comparison of the analgesic effects of modified continuous intercostal block and paravertebral block under surgeon's direct vision after video-assisted thoracic surgery: a randomized clinical trial

Clinical evidence comparing paravertebral (PVB) and continuous intercostal nerve (ICB) blocks for pain management post video-assisted thoracic surgery (VATS) is limited. This study confirms the analgesic effect of ICB using two catheters is not inferior to that of PVB under direct vision. Fifty patients who underwent VATS lobectomy from July 2015 to March 2016 were prospectively recruited and randomly assigned to PVB and ICB groups. Postoperative pain was assessed using the visual analog scale (VAS). VAS score at rest at 24 h was the primary endpoint. Data on time required for catheter insertion, adverse effects, and frequency of additional analgesics as secondary endpoints were also collected. Noninferiority was assessed by adding a VAS margin of 15 mm to the PVB group. No significant differences were observed between the VAS scores of the two groups except at 48 h after surgery, with a margin noted for the PVB group. No significant differences were detected in the frequency of additional analgesics and occurrence of adverse effects. Our results could not clearly establish noninferiority of ICB to PVB. Improvements in ICB may be necessary for it to be used as an alternative method to PVB.