Succinylcholine is a depolarizing neuromuscular blocker frequently used during electroconvulsive therapy. In most patients, the duration of paralysis is brief, allowing for spontaneous respiration shortly after the therapy. We report a case of delayed return of neuromuscular function after succinylcholine administered during electroconvulsive therapy in a 72-year-old man receiving cytarabine, vincristine, and rituximab chemotherapy for chronic lymphocytic leukemia. We hypothesize that an interaction between succinylcholine and one of the chemotherapeutic agents caused the prolongation of paralysis and believe that this is the first reported case of prolonged duration of succinylcholine following this regimen of chemotherapy. Despite this unexpected prolonged neuromuscular blockade, the patient could be treated uneventfully, with attention paid to his respiratory support and with subsequent succinylcholine dose titration to effect.
From the Departments of *Anesthesiology and †Psychiatry, Mount Sinai School of Medicine, New York, NY.
Received for publication September 21, 2010; accepted September 22, 2010.
Reprints: Ethan O. Bryson, MD, Department of Anesthesiology, Mount Sinai Hospital, One Gustave L Levy Pl, New York, NY 10029 (e-mail: firstname.lastname@example.org).
Support was provided solely by institutional and departmental sources.
Owing to its relatively short duration of action, succinylcholine has historically been the muscle relaxant of choice for brief procedures such as electroconvulsive therapy (ECT), which require intense paralysis for only a short period. Interaction between succinylcholine and chemotherapeutic agents could result in potentiated neuromuscular blockade, lengthening the time respiratory support is required after administration.