Efficacy of Erector Spinae Plane Block in Modified Radical Mastectomy for Postoperative Analgesia: A Randomised Controlled Study

Abstract

Introduction: The Erector Spinae Plane Block (ESPB) is a recently introduced Ultrasound (US)-guided interfascial plane block commonly used for treating thoracic neuropathic pain. Although ESPB has been used for pain control after Modified Radical Mastectomy (MRM), which is a frequently performed operation nowadays, its efficacy compared to other methods of pain control is yet to be established. Aim: To evaluate the effectiveness of ESPB in controlling acute postoperative pain after MRM surgery. Materials and Methods: A total of 64 adult females aged between 18-60 years, with American Society of Anaesthesiologists (ASA) physical status I and II, scheduled to undergo elective MRM, were enrolled in the present randomised, double-blinded, controlled study conducted at Department of Anaesthesiology and Critical Care, Nil Ratan Sircar Medical College, Kolkata, West Bengal, India over a period of nine months (from March 2021 to November 2021). They were randomly assigned to two groups, with 32 patients in each group. Group A (n=32) received general anaesthesia only, while Group B (n=32) received US-guided ESPB in addition to general anaesthesia. Postoperative Visual Analogue Scale (VAS) scores, total intra and postoperative analgesic requirements for the first 24 hours, and duration of postoperative analgesia were recorded for each patient. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) version 24.0 software. Mean and Standard Deviation (SD) were used to express data for numerical variables, while count and percentages were used for categorical variables. Results: Demographic characteristics (age, weight), ASA status, and mean duration of surgery were similar between the groups. The duration of postoperative analgesia was significantly (p<0.05) prolonged in Group B patients (584.1±89.1 minutes) compared to Group A patients (78.0±53.1 minutes). Intra and postoperative analgesic requirements were significantly lower in Group B (fentanyl 87.0±16.8 mcg, tramadol 68.3±35.9 mg) compared to Group A patients (fentanyl 94.5±26.7 mcg, tramadol 158.3±32.3 mg). The postoperative VAS score was more favourable in Group B than in Group A (1.1±0.4 vs. 4.1±0.8 at rest). Conclusion: The US-guided ESPB is a simple and easy procedure that provides prolonged duration of postoperative analgesia with reduced overall analgesic requirement in the postoperative period after MRM surgery. Therefore, it can be concluded that ESPB is an effective method for controlling acute postoperative pain after MRM surgery.