An unusual systemic toxicity of mepivacaine following axillary brachial plexus block or femoral/sciatic nerve block in patients with chronic renal failure and/or hypertension: A report of 2 cases

ABSTRACT

There are few reports about the systemic toxicity of mepivacaine, which is widely used for regional nerve blocks, because of its short onset time and intermediate duration, during or after blockades. We report two cases. In the first, a 70 year-old female with chronic renal failure and hypertension was scheduled for arteriovenous fistula formation under axillary brachial plexus block using 30 ml of 1.5% mepivacaine. In the second, a 69 year-old female with hypertension who was scheduled for total knee replacement under femoral/sciatic nerve block with lateral femoral cutaneous nerve block using 45 ml of 1.5% mepivacaine. Both had an exaggerated hemodynamic response (of increased blood pressure and heart rate) with symptoms and signs of central nervous system excitation not evolving to convulsions, which was induced by mepivacaine during or soon after the blockades. Possible causes and mechanisms of the events are discussed based on the literature.