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Acute myotonic reaction during succinylcholine anaesthesia
Saeed Rashaad Mohammed1, Stefan Gafoor2, Avidesh Panday3
1Department of Clinical Medical Sciences, The University of the West Indies at St Augustine Faculty of Medical Sciences, St Augustine, Trinidad and Tobago saeedrashaadtt@gmail.com.
Practical Neurology
|October 3, 2022
Summary
A young woman experienced a severe reaction to anesthesia due to undiagnosed sodium channel myotonia. This case highlights the risks of succinylcholine in patients with myotonic disorders.
Area of Science:
- Neurology
- Anesthesiology
- Medical Genetics
Background:
- Neuromuscular disorders increase perioperative risks.
- Myotonia can lead to severe anesthetic complications.
- Succinylcholine can trigger acute myotonic reactions.
Observation:
- A 21-year-old woman developed an acute myotonic reaction during anesthesia with succinylcholine.
- Clinical examination revealed myotonia, ptosis, and muscle hypertrophy.
- Neurophysiology confirmed continuous myotonic discharges.
Findings:
- Genetic analysis identified a SCN4A gene mutation (c.3917G>A, p.Gly1306Glu).
- Diagnosis of sodium channel myotonia was confirmed.
- The patient's myotonic disorder was previously unrecognized.
Implications:
- Depolarizing agents like succinylcholine are contraindicated in patients with myotonia.
- Early diagnosis and awareness of myotonic disorders are crucial for safe anesthesia.
- This case underscores the importance of perioperative screening for neuromuscular conditions.
Keywords:
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