Ultrasound-Guided Continuous Transmuscular Quadratus Lumborum Block for Postoperative Analgesia in Patients Undergoing Radical Nephrectomy: A Randomized Controlled Trial

Introduction Ultrasound (US) guided transmuscular quadratus lumborum block (TMQLB) has been widely used as regional anaesthesia (RA) technique for managing postoperative pain after intraperitoneal and retroperitoneal procedures like nephrectomy, percutaneous nephrostomy, cholecystectomy, and also for hip surgeries. Although continuous epidural analgesia is considered the gold standard for most of these procedures, alternative techniques such as transversus abdominis plane (TAP) block and continuous rectus sheath block have also been used successfully. US-guided TMQLB seems to have more advantages than TAP block as it blocks the visceral afferents. With more cephalad spread of the local anaesthetic into the thoracic paravertebral space, it might block somatic pain from T6 to L2 as well. Methods After institutional ethics committee approval, we recruited 64 consecutive patients in the study and randomized them into two groups. Patients in the study group received bupivacaine (0.125%) and the control group received normal saline as a continuous infusion for 48 hours. Both groups were compared for 48 hours morphine consumption, time to first analgesic, hemodynamics, postoperative nausea/vomiting (PONV), sedation, and other adverse events. Results Data from 60 patients were analyzed. Forty-eight hours of morphine consumption in group A (study) was less than group B (7.4 ± 4.57 mg versus 11.86 ± 5.58 mg) and the time to first morphine requirement was 240 min (105-500) in group A compared to 90 min (90-225) in group B which was statistically significant. Demographic data, American Society of Anesthesiologists physical status, hemodynamics, Ramsay sedation score (RSS), and PONV were comparable in both groups. Conclusion Continuous US-guided TMQLB appears to be a safe and effective RA technique for managing postoperative pain after nephrectomy for up to 48 hours. Trial registration: German Clinical Trials Register-DRKS-ID: DRKS00014611.