A recent meta-analysis depicted that the postsurgery analgesic effect of the paravertebral block (PVB) is superior to erector spinae plane block (ESPB) for thoracic operation. For breast surgery, the postsurgery analgesic effects of ESPB and PVB are comparable. This study was carried out for investigating the postoperative pain-relieving effects of PVB vs. ESPB in thoracic and breast surgery.

Databases like EMBASE, PubMed, Science Direct, Cochrane Library, Web of Science were systematically explored. Postsurgery pain scores was the major endpoint, while the secondary endpoints were opioid intake, additional analgesia need, postoperative nausea and vomiting (PONV) 24 hours after surgery, and time needed for completion of block procedure.

Following screening relevant, full-text articles, 10 randomized controlled trials (RCTs) that met the study's inclusion criteria were obtained. Overall, 6 studies involved thoracic surgery people, and 4 included breast surgery people. The thoracic surgery studies incorporated all of the outcomes ascertained in this study. On the other hand, breast operation did not describe pain scores at movement and the need for additional analgesia in 24 hours after the operation.

For thoracic surgery, PVB led to a considerable decline in the following pain scores: 0-1 hours (MD = -0.79), 4-6 hours (MD = -0.31), and 24 hours (MD = -0.42) at rest; substantial drop in pain scores at 4-6 hours (MD = -0.47), 8-12 hours (MD = -1.09), and 24 hours (MD = -0.31) at movement. Furthermore, opioid intake at 24 hours after surgery (MD = -2.74) and the occurrence of additional analgesia in 24 hours of the postsurgery course (RR: 0.53) were remarkably reduced in the PVB arm when compared to the ESPB arm for thoracic surgery.

No profound differences were witnessed in the pain scores at rest at different time points after operation, and opioid intake at 24 hours after breast operation. Compared to the ESPB group, the PVB group displayed a longer time for completion of the block procedure for thoracic and breast surgery. There were no considerable differences in the occurrence of PONV between PVB and ESPB groups. Thus, for thoracic surgery, PVB should be used, while for breast surgery, ESPB is suggested.