Authors: Billy Sun
Reviewers: Joseph Tropiano Melinda Davis, MD
Succinylcholine (Depolarizing Neuromuscular Blocker)
Abbreviations ACh — Acetylcholine SA — Sino-atrial
Quick Facts 1° Indication = Skeletal muscle paralysis to allow tracheal intubation with the advantage of faster onset (30s-60s) and shorter duration (<10min) than non-depolarizing neuromuscular blocking agents Route of Administration = IV Metabolism & Excretion = redistribution and metabolism by pseudocholinesterase in blood plasma and liver No reversal of succinylcholine available Contraindicated in patients with traumatized, denervated, or immobilized muscles due to risk of cardiac arrest from hyperkalemia. Agonist at nicotinic ACh receptors in muscles Generates action potential Not affected by synaptic acetylcholinesterase (unlike ACh) Continuous end-plate depolarization Inactivation of sodium channels Prevention of repolarization and additional action potentials Skeletal muscle paralysis Succinylcholine mimics ACh in structure ♦ Fasciculation ♦ Myalgia 1` Serum lc (esp. in patients with muscle trauma/denervation/ immobilization) 1 Hyperkalemia Malignant Hyperthermia (See Slide) Agonist at nicotinic receptors in parasympathetic ganglia, sympathetic ganglia, and muscarinic receptors in SA node of heart Parasympathetic effect (low dose succinylcholine) 4, Heart rate 4, Contractility Cardiac arrest 1 Sympathetic effects (high dose succinylcholine) t Heart rate t Contractility Catecholamine release Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications I Published March 3, 2018 on www.thecalgaryguide.com 0€3,0 BY NC SA