Effect of Ultrasound-Guided Thoracolumbar Interfascial Plane Block on the Analgesic Requirements in Patients Undergoing Lumbar Spine Surgery Under General Anesthesia: A Randomized Controlled Trial

BACKGROUND: Thoracolumbar interfascial plane (TLIP) block was recently described as a regional anesthetic technique to achieve analgesia for lumbar spine surgery by blocking the dorsal rami of spinal nerves. The study aims to test the hypothesis that TLIP block can offer pain control and reduce the perioperative analgesic requirement in patients undergoing spinal surgery. METHODS: There were 60 patients scheduled for lumbar spine surgery who were randomly assigned into two equal groups, TLIP and control groups. Patients in the TLIP group received general anesthesia and TLIP block while patients in the control group received general anesthesia alone. The primary outcome was the analgesic consumption in the first postoperative 24 hours, while intraoperative additional analgesic needs, time to the first request of postoperative analgesia, and pain scores were the secondary outcomes. RESULTS: At 24 hours postoperatively, morphine consumption was lower in the TLIP group (5.13±1.55) versus the control group (14.33±2.58) mg. The intraoperative fentanyl consumption was lower in the TLIP group (15±35.11 mcgs) versus the control group (105±62.08 mcgs). Postoperative first request for analgesia was delayed in the TLIP group (7.30±2.69 h) compared to the control group (0.92±1.23 h). Postoperative Pain scores at rest were 2.53 ± 0.97 and 3.43 ± 0.50 at 24 hours in the TLIP group and the control group, respectively. Postoperative Pain scores at passive flexion of spine were 2.73 ±0.87 and 3.93 ±0.78 at 24 hours in the TLIP group and the control group, respectively. Patients in the TLIP group had lower perioperative hemodynamic responses to surgical stimulation in comparison to the control group. CONCLUSION: Combined TLIP block with general anesthesia in patients undergoing spinal surgery reduced both postoperative and intraoperative analgesic needs, reduced intra-operative hemodynamic response to surgery, and achieved good postoperative pain control.