title: [Direct potentiometric determination of the level of cyanide in plasma following an infusion of sodium nitroprusside].
abstract: Plasma cyanide concentrations were measured potentiometrically in 12 patients before and after infusion of sodium nitroprusside (SNP). A close correlation was found between the increase in plasma cyanide level and the total dose of SNP and between the increase and the mean rate of SNP infusion. After a total dose of 3.1 mumol SNP/kg (0.924 mg/kg) the maximum plasma cyanide concentration amounted to 2.2 mumol/1 (57 micrograms/l) which is lower than the recommended upper limit of 3 mumol/l plasma (78 micrograms/l); but indicates the importance of the recommended maximum dose of 5 mumol SNP/kg (1.5 mg/kg) and the control of plasma cyanide levels under SNP treatment. The direct potentiometric evaluation of the plasma cyanide level using the indicator method seems to be useful for such a control because it is more sensitive and faster than spectroscopic methods. The time needed for performing one measurement is about 35 minutes.
authors.forename: H
authors.initials: H
authors.lastname: Steinecke
authors.forename: U
authors.initials: U
authors.lastname: Heesen
mesh_terms: D000328:Adult; D005260:Female; D005292:Ferricyanides / Q000627:therapeutic use*; D006801:Humans; D007023:Hypotension, Controlled; D002532:Intracranial Aneurysm / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009599:Nitroprusside / Q000032:analysis / Q000627:therapeutic use*; D011199:Potentiometry / Q000379:methods
chemical_list: D005292:Ferricyanides; D009599:Nitroprusside
vernacular_title: Direktpotentiometrische Bestimmung von Cyanid-Plasmaspiegeln nach Infusion von Nitroprussid-Natrium.