Electroconvulsive therapy and muscle relaxants.

the editor, “the Electroconvulsive therapy in a catatonia patient: succinylcholine or no succinylcholine?” Neuromuscular blocking agents are important drugs for electroconvulsive therapy (ECT) to prevent possible musculoskeletal complications of ECT, such as hyperkalemia, myalgia, dislocation, and fracture. Succinylcholine is more effective because it typically has a fast onset and short duration of action. However succinylcholine may induce myalgia, hyperkalemia, and malignant hyperthermia [1]. Therefore, the anesthetic provider should preoperatively evaluate the patients’ physical status and laboratory tests, and select anesthetics with neuromuscular blocking agents [2,3]. Nicotinic acetylcholine receptors (nAChRs) on the neuromuscular junction are upor down-regulated in neuromuscular diseases, burns, and upper or lower motor nerve injury. Upregulation of nAChRs increases sensitivity to depolarizing neuromuscular blocking agents (e.g., succinylcholine), while downregulation increases resistance to depolarizing neuromuscular blocking agents [4]. Supersensitivity to nAChR agonists (e.g., acetylcholine or succinylcholine) was observed throughout the muscle membrane. The increase in nAChRs after denervation is more profound and occurs more quickly than with simple immobilization [4]. In this case, succinylcholine was avoided because of the risk of life-threatening hyperkalemia resulting from the upregulation of nAChRs secondary to long-term immobilization, as the patient had been immobilized due to catatonia for the past 6 months. Glycopyrrolate (0.2 mg), propofol (80 mg), and atracurium (15 mg) were administered. I-gel insertion and propofol infusion were started for maintenance until recovery from the neuromuscular blockade in the first and second ECT sessions, respectively. In the third ECT session, succinylcholine was used instead of atracurium to monitor, diagnose, and manage the hyperkalemia. The intraoperative course remained uneventful with no electrocardiographic changes suggestive of hyperkalemia [1]. In this Letter to the Editor Anesth Pain Med [Epub ahead of print] https://doi.org/10.17085/apm.23018 pISSN 1975-5171 • eISSN 2383-7977