Sodium nitroprusside in children: Observations on metabolism during normal and abnormal responses.
Three different responses to sodium nitroprusside as a hypotensive agent during anaesthesia in children are described. A constant high dose (greater than 3 mg/Kg) response to, abnormal resistance to and tachyphylaxis to the drug are recognised and are dangerous and potentially lethal. They are probably related to abnormalities of cyanide-thiocyanate metabolism resulting in cyanide accumulation. The abnormal responses produce metabolic acidosis, an increase in mixed venous oxygen tension and a decrease in arterial mixed venous oxygen content difference. Tachyphylaxis may be due to depletion of endogenous thiosulphate and was reversible by sodium thiosulphate therapy (150 mgm/Kg) in two cases in which it was used.
D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003486:Cyanides / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004341:Drug Evaluation; D004351:Drug Resistance; D005260:Female; D005292:Ferricyanides / Q000378:metabolism*; D006801:Humans; D007023:Hypotension, Controlled; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009599:Nitroprusside / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D010100:Oxygen / Q000097:blood; D012737:Sex Factors; D013618:Tachyphylaxis; D013997:Time Factors
D003486:Cyanides; D005292:Ferricyanides; D009599:Nitroprusside; D010100:Oxygen