[Ultrasound-assisted neuraxial anesthesia in a patient with previous lumbar laminectomy and fusion: a case report].

A patient with previous L3-4 posterior lumbar interbody fusion, pedicle screws instrumentation and L3-4 decompression, was scheduled for left total hip arthroplasty. Two years ago, due to poor landmarks palpation, the patient experienced a failed lumbar puncture after multiple attempts before herniorrhaphy. His plain radiography showed bilateral partial laminectomy at L3-4 level, and between L3 and L4, two posterior pedicle screws connected by metal rods on both sides. This time, we used ultrasound to locate L4-5 interlaminar space in paramedian sagittal oblique view and identified the spine midline by transverse interlaminar view before puncture. According to this information, L4-5 puncture point was verified and the combined spinal-epidural anesthesia was performed in a paramedian approach. After withdrawing clear cerebral spinal fluid, 15 mg hyperbaric bupivicaine was injected into intrathecal space. An epidural catheter was then inserted into the epidural space. The sensory block level was fixed at T10 to S within 10 minutes. Intraoperatively, the patient received 10 mL 2% (mass fraction) lidocaine through the epidural catheter in total. The surgery was uneventful. No neurologic complication was observed after the surgery. This case report demonstrates that ultRASound imaging can provide useful information for neuraxial needle placement and can be a valuable tool in managing patients with anatomical change around the spine.