Comparison of midpoint transverse process to pleura (MTP) block and erector spinae plane block (ESP) for postoperative analgesia in modified radical mastectomy patients: A double-blinded, randomized control trial.

Background and aims: Modified radical mastectomy (MRM) is associated with moderate severity of postoperative pain. Besides intravenous (IV) analgesics, various nerve blocks are being described for pain relief of MRM patients. We compared erector spinae plane (ESP) block with midpoint transverse process to pleura (MTP) block in these patients for postoperative analgesia.

Material and methods: After receiving ethical committee approval from the institutional ethics committee (AIIMS, Jodhpur) and written informed consent from study participants, 66 patients who were assigned American Society of Anesthesiologists (ASA) physical status I and II, aged 18-75 years, and were scheduled to undergo MRM were enrolled and randomly allocated into two groups. Unilateral block was given before surgery at T3 or T4 level and with 15 ml of 0.5% ropivacaine in both the groups. Infusion of 0.5% ropivacaine (Neon laboratories limited, Mumbai, India) and 0.2% ropivacaine at a rate of 5 ml/h was maintained intraoperatively and postoperatively, respectively. Pain was assessed using the Visual Analogue Scale (VAS) for the next 24 hours. The total number of patients needing rescue analgesia, the total amount of rescue analgesics consumed in the next 24 hours, and patient satisfaction score were also compared between groups.

Results: Demographics and baseline vitals were comparable in the groups. On comparing VAS scores in both the groups during rest and movement at different time intervals, there was no difference in pain scores during the initial two hours. From the third hour, there was a statistically significant difference (P < 0.001) in pain VAS scores in both groups. The ESP group had lower VAS scores compared to the MTP group when followed for the next 24 hours. There was a statistically significant difference in patient satisfaction.

Conclusion: ESP block is more efficacious when compared to MTP block for postoperative analgesia in MRM patients.