Background: Ideal regional nerve block analgesia should theoretically achieve maximum pain relief without interfering with early ambulation, or causing serious side effects. The same also applied to hip and proximal femur surgeries.
Objective: To compare the duration of postoperative analgesia provided by different approaches of quadratus lumborum analgesia (QLB-1/ QLB-2/ QLB-3), in orthopedic lower limb surgery under subarachnoid anesthesia.
Patients and Methods: This study was conducted in Orthopedic surgery operating unit from July 2020 and ended at August 2021 in Al-Azhar University Hospitals (Al-Hussein and Sayed Galal), and approved by the ethics committee from the Department of Anesthesia of Faculty of Medicine, Al-Azhar University. Patients gave written informed consents. 120 patients who were scheduled for orthopedic lower limb surgeries under subarachnoid anesthesia (30 controls and 90 cases divided into three subgroups randomly). Once enrolled, patients were randomly assigned into four equal groups: QLB-1 group has received (lateral QLB), QLB-2 group has received (posterior QLB), QLB-3 group has received (transmuscular QLB). QL blocks were done using 20 ml of Bupivacaine 0.25 %, and SAB control group has received (subarachnoid anesthesia only). The following parameters were monitored: time of requirement of first analgesia, total doses of rescue morphine and Visual Analogue Scale (VAS) at the following intervals: immediately and at 2 / 6 / 12 and 24 hours postoperatively.
Results: The time of requirement of first analgesia significantly prolonged in QLB-3 compared to QLB-1, QLB-2 and SAB control and prolonged in QLB-1 and QLB-2 than SAB control with insignificant differences between QLB1 and QLB-2. The total doses of rescue morphine were significantly lower in QLB-3 compared to QLB-1, QLB-2 and SAB control, and lower in QLB-1 and QLB-2 than SAB control with insignificant differences between QLB1 and QLB-2. VAS was significantly different among the four groups at 2, 12 and 24 hours (P <0.001) but was insignificantly different at PACU and 6 hours. VAS at 2 hours was significantly lower in QLB-3 compared to QLB-1, QLB-2 and SAB Control but with insignificant differences among QLB1, QLB-2 and SAB control group. VAS at 12 and 24 hours were significantly lower in QLB-3 compared to QLB-1, QLB-2 and SAB Control and lower in QLB-1 and QLB-2 than SAB Control with insignificant differences between QLB1 and QLB-2.
Conclusion: Ultrasound-guided Transmuscular Quadratus Lumborum Block, using 20 ml of Bupivacaine 0.25 %, prolonged the duration of analgesia, decreased morphine consumption and improved pain relief score compared to Lateral and Posterior Quadratus Lumborum Block in patients undergoing proximal lower limb surgery under subarachnoid anesthesia.