Does Administration of the Transmuscular Quadratus Lumborum Block Cause Quadriceps Muscle Weakness: A Randomised, Double-blinded Volunteer Study

The ideal postoperative analgesic regimen following major abdominal and retroperitoneal laparoscopic surgery still lacks consensus and the discussion is ongoing. The epidural blockade has been the gold standard for postoperative pain management for major abdominal surgery for years, but with the conversion to minimal invasive surgery the procedure can rarely be justified.

The use of a multimodal analgesic regimen with opioids can cause severe side effects. These side effects can delay mobilisation after surgery, increase the risk of complications and worst of all be fatal.

The focus on an opioid sparing regimen, in the enhanced recovery setting, has been a significant motivator for the addition of ultrasound-guided nerve blocks to the perioperative progression.

At the Department of Anaesthesiology, Zealand University Hospital, the ultrasound-guided Transmuscular Quadratus Lumborum (TQL) block is part of the perioperative pain regimen for major laparoscopic abdominal and retroperitoneal surgeries, as well as for elective caesarean sections. Using the visual guidance of ultrasound, the injectate of local anaesthetic is administered in the fascial interspace between the quadratus lumborum muscle and the psoas major muscle posterior to the transversalis fascia.

This will anaesthetise the abdominal wall including both somatic and visceral nerves. No involvement of lumbar plexus i.e. the femoral nerve, obturator nerve or the lumbar part of the sympathetic trunk was observed. The lack of lumbar plexus involvement means no motor block of the lower extremities should be observed. Previous clinical studies reported no adverse events. However, the investigators did not specifically register lower limb weakness or hypotension, but on the other hand did not find any difference in ambulation or even faster ambulation compared to the placebo group.