An antero‐lateral approach to ultrasound‐guided lumbar plexus block in supine position combined with quadratus lumborum block using single‐needle insertion for pediatric hip surgery

Sir—We read with great interest this paper regarding psoas compartment block. Recently, some ultrasound-guided techniques have become common in clinical practice. However, all techniques for psoas compartment block require postural change of the patient to lateral decubitus position. We would like to present our original technique for lumbar plexus block combined with quadratus lumborum block using single-needle insertion in supine position in a pediatric case. Oral and written informed consent for publication of the patient’s data and accompanying image were obtained from the parents of the patient. An 8-year-old girl (height, 130 cm; weight, 31 kg) with acetabular dysplasia and no significant medical history was scheduled for periacetabular osteotomy (anterior approach in supine position) under general anesthesia. After the surgery, ultrasound-guided lumbar plexus block and transmuscular quadratus lumborum block were performed in the operating room in the same position. A linear transducer (4.2-13 MHz) was placed in the transverse plane at the abdominal flank. Then, the transducer was moved dorsally and tilted cephalad maintaining the transverse orientation until the quadratus lumborum muscle was identified with its attachment to the lateral edge of the transverse process of the L3 vertebral body with the psoas major muscle anteriorly. The needle was inserted in-plane to the transducer (antero-lateral edge), and the tip of the needle was advanced through the transversalis fascia; 10 mL of 0.3% ropivacaine was injected adjacent to lumbar plexus within psoas major muscle, and finally 10 mL of 0.3% ropivacaine between the quadratus lumborum muscle and psoas major muscle (Figure 1). Fentanyl (155 mcg) and acetaminophen (450 mg) were administered intraoperatively. Surgery and anesthetic procedures were uneventful, and our standard postoperative analgesic regimen was followed (scheduled acetaminophen). Patient had cold loss from T11 to L4. The patient slept well, had no pain, and did not require rescue analgesics for 14 hours after the procedure. Our method has been used in several following cases at Chiba Children’s Hospital, mainly for postoperative pain relief. There was no apparent complications concerning this technique, and similar effects and postoperative courses have been achieved. In this presented case, considerable and long-duration pain relief was achieved using single-shot lumbar plexus block combined with transmuscular quadratus lumborum block. Particularly, this ultrasound-guided approach was useful in eliminating the need for postural change, and it is no danger of misalignment of pelvis even after hip surgery under general anesthesia, especially in children who have thin abdominal wall and little visceral fat, whence the depth of lumbar plexus is shallower in these populations. Nerve stimulation (0.5-1 mA, 0.1 ms impulse duration) can be used to confirm correct needle placement to lumbar plexus with certainty. In this combined block, lumbar plexus block should be performed in advance of transmuscular quadratus lumborum block because prior local anesthetics deposition between the quadratus lumborum muscle and psoas major muscle can reduce the intensity of lumbar plexus stimulation. Transmuscular quadratus lumborum block mainly targets the subcostal (Th12) and the iliohypogastric, ilioinguinal nerves (L1), spreading into the thoracic paravertebral space to reach the somatic nerves. This anesthesia is important for cutaneous pain relief following hip surgery. Sole usefulness of transmuscular quadratus lumborum block for hip surgery has been reported recently, and longF IGURE 1 Representative ultrasound images of needle and local anesthetics (LA) for lumbar plexus block (LPB) and transmuscular quardratus lumborum (TQL) block, and ultrasound-guided needle insertion positioning. Arrow heads indicate pathway of the needle; TP: transverse process; VB: vertebral body; LP: lumbar plexus; QLM: quadratus lumborum muscle; PMM: psoas major muscle Accepted: 7 June 2017