Paravertebral block via the surgical field versus epidural block for patients undergoing thoracotomy: a randomized clinical trial.

PURPOSE: A paravertebral block (PVB) given via the surgical field can be safer and technically simpler than an epidural block (EP) for postoperative pain control. We conducted this clinical trial to confirm the effectiveness of PVB after thoracotomy. METHODS: In this non-inferiority trial, patients were randomly assigned to receive PVB (n = 35) or EP (n = 35). The primary endpoint was the pain assessed using the visual analog scale (VAS) at rest, 2, 24, and 48 h after thoracotomy, with the non-inferiority margin set at 15 mm. The secondary end points were the pain assessed using the VAS on exercising and on coughing, 2, 24, and 48 h after surgery, respectively, and the complications and need for additional analgesic agents. RESULTS: This trial revealed that PVB was not inferior to EP with respect to the primary end point: The mean VAS scores at rest, 2, 24, and 48 h after thoracotomy were 26.3, 10.8, and 8.3 mm in the PVB group and 23.6, 12.4, and 12.6 mm in the EP group, respectively (P < 0.01 for non-inferiority at all points). There were no significant differences between the groups in the incidence of complications or the need for additional analgesic agents. CONCLUSION: PVB may replace EP for postoperative pain control because of its technical simplicity and safety.