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[Prolonged apnea after administration of succinylcholine]
1Institut za hirurgiju, Medicinski fakultet, Vojnomedicinski centar, Novi Sad.
Medicinski Pregled
|June 5, 1998
Summary
Prolonged apnea after succinylcholine anesthesia can indicate a genetic deficiency in acetylcholinesterase enzyme. This case highlights the importance of pre-anesthetic evaluation for patients with potential enzyme abnormalities.
Area of Science:
- Anesthesiology
- Biochemistry
- Pharmacology
Background:
- Succinylcholine is a widely used depolarizing muscle relaxant.
- Its metabolism relies on the enzyme acetylcholinesterase, synthesized in the liver.
- Metabolism can be prolonged in cases of liver dysfunction, pregnancy, or genetic acetylcholinesterase deficiencies.
Observation:
- A 31-year-old woman experienced 90-minute apnea following succinylcholine administration during a diagnostic endometrial biopsy.
- This prolonged apnea was consistent with three previous anesthetic events.
- Laboratory tests revealed decreased plasma acetylcholinesterase levels (20 mU/L).
Findings:
- The patient exhibited a significant deficiency in acetylcholinesterase activity.
- The incidence of individuals with deficient acetylcholinesterase (recessive homozygotes) is estimated at 1:1500–1:3000.
- Apnea duration in such cases can range from 1 to 8 hours.
Implications:
- Comprehensive pre-anesthetic history is crucial for identifying patients at risk of prolonged apnea.
- Anesthesiologists must be prepared to manage prolonged apnea by ruling out other causes and providing supportive care.
- Despite risks, succinylcholine remains in use due to the lack of suitable alternatives.
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