Profound Prolonged Bradycardia and Hypotension after Interscalene Brachial Plexus Block with Bupivacaine

Abstract

BackgroundInterscalene brachial plexus blocks have been a routinely performed method of anesthesia for shoulder surgery that decreases the need for general anesthesia, length of stay, and recovery time. We describe a case of bupivacaine toxicity after an interscalene block. Case ReportThe patient was a 66-year-old man who presented to our Emergency Department by emergency medical services from an ambulatory surgery center where he had undergone rotator cuff surgery, with bradycardia and hypotension. His symptoms began upon completion of the surgery in which he received interscalene nerve block with bupivacaine and lidocaine. He was given three doses of 0.5 mg atropine and one dose of 1 mg epinephrine for a heart rate of 40 beats/min without any improvement prior to arrival. His bradycardia was refractory to atropine. He was started on a dopamine drip and transferred to the coronary care unit. The timing of his symptoms, minutes after his regional nerve block, and his complete recovery with only supportive care, make the diagnosis of bupivacaine toxicity likely. Why Should an Emergency Physician Be Aware of This?Despite the safety profile of local anesthetics, we must be aware of their potential side affects. Whereas most adverse reactions are secondary to misdirection of anesthetic or accidental vascular puncture, local anesthetic systemic toxicity (LAST) is the major cause of significant adverse events with regional anesthesia. As regional anesthesia becomes more common, emergency physicians must be more aware of the potential complications and be able to both diagnose and treat.