Comparison of the postoperative analgesic efficacy of the ultrasound-guided erector spinae plane block and intrathecal morphine in patients undergoing total abdominal hysterectomy under general anesthesia: a randomized controlled trial

Purpose Total abdominal hysterectomy (TAH) is a common surgical procedure. Erector spinae plane block (ESPB) and intrathecal morphine (ITM) provide adequate postoperative (PO) analgesia. However, ITM side effects may limit its use. Researchers investigated the efficacy of bilateral ultrasound-guided ESPB on PO pain and analgesic consumption compared to ITM in the first 24 h following TAH under general anesthesia. Methods 120 patients premedicated with 3 mg intravenous granisetron were randomized into three equal groups: bilateral ultrasound-guided ESPB, ITM or control group. The primary outcome of this study was the time to first request for a rescue analgesic (tramadol). Results Compared to the control group, the ESPB and ITM groups showed higher time to first request for a rescue analgesic and lower total tramadol consumption 24 h following surgery (P < 0.001) with significant differences between the ESPB and ITM groups (P < 0.001). The ITM group showed lower pain scores and lower readings of both serum glucose and cortisol levels compared to the other two groups 24 h after surgery (P < 0.001). The ITM group also had higher incidences of nausea and pruritus 24 h after surgery (P < 0.001). The use of a single intrathecal injection of 0.3 mg morphine did not show any respiratory depression. Conclusion 0.3 mg intrathecal morphine was superior to erector spinae plane block for postoperative pain relief, 24 h after surgery, regarding attenuated stress response, lower pain scores at rest and on coughing and lower tramadol consumption.