Efficacy of different local anaesthetic volumes during erector spinae block for postoperative pain management in patients undergoing open nephrectomy operations. A randomized controlled study

ABSTRACT Background Pain control after surgery is of highest priority. Erector spinae plane block [ESPB] was reported to be a successful method to reduce pain scores and consumption of postoperative opioids. However, hardly any investigation has looked at the ideal volume of bupivacaine for ESPB. So, this work tried to fill this gap of literature in patients undergoing simple nephrectomy. Methods In this randomized double blinded control study, 100 cases undergoing simple nephrectomy were randomized into 4 groups with 25 patients per group. Group E1, 2, and 3 received ESPB with 2.5, 3.4, and 6.6 ml/segment of 0.25% bupivacaine, respectively, whereas there was no block given to the control group. Intraoperative fentanyl consumption, heart rate [HR] and the blood pressure [BP], Postoperative morphine consumption, time passed to first analgesic request, numerical rating score [NRS] of pain, the complications, HR and BP were documented for 24 hours after the operation. Results The reduction in intraoperative fentanyl consumption, postoperative morphine consumption and NRS were a significantly different between the block groups and control. Group E3 had significant difference from other groups with the longest time to first analgesia request. A lower HR was shown in block groups but within normal range. BP showed insignificant difference between groups. There were no reported complications in all study groups. Conclusions The volume of 6.6 ml/level was associated with the best pain control, without significant hemodynamic changes or adverse events as compared to other groups. This suggests that this volume may be the optimal for ESPB in patients undergoing simple nephrectomy.