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qqqqq57 - ebnalfady - ArchivalUser - 02-28-2008

Acute intermittent porphyria is a contraindication of the use of which of the following?
A.
Enflurane
B.
Nitrous oxide (N2O)
C.
Ketamine
D.
Diazepam
E.
Thiopental



0 - ArchivalUser - 02-28-2008

bb


0 - ArchivalUser - 02-28-2008

The answer is: E

Induction of anesthesia by parenteral administration of thiopental sodium and other barbiturates is absolutely contraindicated in patients who have acute intermittent porphyria. These patients have a defect in regulation of -aminolevulinic acid synthetase; thus, administration of a barbiturate that increases this enzyme may cause a dangerous increase in levels of porphyrins. Administration of a barbiturate would exacerbate the symptoms of gastrointestinal and neurologic disturbances, cause extensive demyelination of peripheral and cranial nerves, and could lead to death