Ineffectiveness of intralipid infusion for central nervous toxicity following ultrasound-guided sciatic nerve block with lidocaine-ropivacaine solution: interaction between carbamazepine, local anaesthetic and intralipid?

摘要

A 51-year-old ASA 2 female patient (height 157 cm, weight 57 kg) presented for left hallux valgus surgery under sciatic nerve block. Six months previously she had undergone an uneventful ultrasound-guided sciatic nerve block with 5 mg ml~(-1) levobupivacaine (100 mg) performed for the same surgical procedure on the contral-ateral side. She suffered from a trigeminal neuralgia diagnosed 3 months before and was treated with carba-mazepine twice daily (200 mg in the morning and 400 mg in the evening) not interrupted before surgery. A 20-gauge peripheral venous catheter was inserted and 31 min~(-1) oxygen was delivered via nasal prongs. No intravenous sedation was used during the block performance. Heart rate (with a three-lead ECG), noninvasive blood pressure and oxygen saturation were monitored continuously during the procedure. Baseline blood pressure, room air oxygen saturation and heart rate were 134/ 67mmHg, 99% and 65 beats min~(-1), respectively.