Ultrasound Guided Erector Spinae Plane Block and Quadratus Lumborum Block for Postoperative Analgesia in Patients Undergoing Total Abdominal Hysterectomy: A Comparative Study

Background: Quadratus lumborum block is a peripheral block method that has been used successfully for pain relief after total abdominal hysterectomy. Prolonged analgesia has been reported as compared with more conventional transversus abdominis plane (TAP) block. Erector spinae plane (ESP) block is a novel interfascial plane block used in postoperative pain and chronic neuropathic pain relief of the thoracoabdominal region. Recently it has been used as a postoperative regional analgesia technique in different surgeries from the shoulder to hip regions due to its simplicity and efficacy. This study was designed to compare the efficacy of ultrasound guided erector spinae plane block and quadratus lumborum block for postoperative analgesia in patients undergoing total abdominal hysterectomy.Methods: This randomized prospective double-blinded comparative study was carried out form July 2021 to June 2022 at Dhaka Medical College. A total of 60 patients were enrolled in this study and randomized into two groups (ESPB and QLB-2). 1st group (Group: ESPB): received bilateral ultrasound-guided Erector Spinae Plane (ESPB) block with each block 20ml of 0.25% bupivacaine at the level of T9, 2nd group (Group: QLB-2): received bilateral ultrasound-guided posterior Quadratus Lumbroum block (QLB-2) with the same volume and concentration of bupivacaine. Following parameters were observed, recorded and compared between two groups: postoperative pain intensity using VAS score, the total amount of opioid consumption in the first 24 hours after the operation, the time of first rescue analgesia and possible adverse events such as hypotension, nausea/vomiting, shivering, dizziness, itching etc. during the postoperative period.Results: There were no significant differences found according to demographic and clinical status between two groups. The failed block rate was high in group B which was 13.3% (p = 0.011). At 16th and 24th hour mean heart rate (HR), SBP & MAP were significantly higher in group B (p < 0.05) than group A. In Group A mean HR, SBP & MAP were higher at 20th hour than group B and statistically significant differences (p < 0.05) observed. After assessing VAS score during postoperative period, it was observed that VAS score was significantly higher in group B, at 16th and 24th hour (p < 0.05) than group A. In group A, VAS score was higher than group B at 20th hour and found statistically significant (p < 0.05). Time of first rescue analgesia (hrs) for ESP group and QLB group were 20±1.4 hours & 16.7±1.2 hours respectively and the difference was statistically significant (p < 0.05). Total opioid (pethidine) requirement in 1st 24 hours (mg) was significantly higher (136.8±9.4 mg) in QLB group than ESP group (79.6±8.6 mg) as p < 0.05. Incidence of adverse events like nausea (23.08%), vomiting (15.4%) and itching (19.2%) were higher in group B then group A which were also statistically significant (p < 0.05).Conclusion: After total abdominal hysterectomy under SAB, ESP block provide longer duration of analgesia, low VAS score during postoperative period with less requirement of opioid in 1st 24 hours as well as lower postoperative complications when compared to QL block-2.