Analgesic efficacy of posterior and anterior psoas compartment block: Lumbar plexus versus three -in-one nerve block after lower limb orthopedic surgery under spinal anesthesia: A prospective cohort study.

Introduction: Postoperative pain is the most common complaint in patients who underwent orthopedic surgery. Regarding with the severity of pain, orthopedic patients suffered more than non-orthopedic patients in the immediate post-operative period. Therefore, pain management is crucial for better patient outcome. Lumbar plexus (LB) and three -in-one (3IN1) nerve blocks have been routinely practiced as pain management techniques in the study area but the analgesic efficacy was not studied yet. Thus, this study was aimed to compare the analgesic efficacy of the LBP versus 3IN1B as postoperative pain management after thigh orthopedic surgery under spinal anesthesia.

Method: An institutional-based prospective cohort study was conducted from October 10, 2020 to March 30, 2021 at the University comprehensive specialized hospital. Non-probability convenient sampling was used to select participants in both groups. The time to first analgesic request, severity of pain and total analgesia consumption within the first postoperative 24 h were measured.

Result: The mean and standard deviation to seek the first analgesia request time was 11. 55 ± 2. 82hr and 13. 35 ± 2. 58hr (p- 0.07) in patients who received LPB and 3IN1B respectively. Pain severity at rest and on movement was also comparable. The total tramadol consumption was 67. 65 ± 27. 20 mg and 70. 59 ± 37. 19 mg (p- 0.71), while total Diclofenac consumption was 63. 23 ± 45. 74 mg and 44. 88 ± 34. 72 mg (p-0.07) in LPB and 3IN1B groups respectively.

Conclusion: The study showed that there was no significant difference in the time to first analgesia request, postoperative pain, both at rest and movement and total analgesic consumption, between the LPB and 3IN1B.