title: Prospective study of hydroxocobalamin for acute cyanide poisoning in smoke inhalation.
abstract: OBJECTIVE
  To assess outcomes in patients treated with hydroxocobalamin at the fire scene or in the ICU for suspected smoke inhalation-associated cyanide poisoning.
  
  
  METHODS
  Adult smoke inhalation victims with suspected cyanide poisoning as determined by soot in the face, mouth, or nose or expectorations and neurologic impairment received an intravenous infusion of hydroxocobalamin 5 g (maximum 15 g) at the fire scene or in the ICU in this observational case series conducted from 1987 to 1994. Blood cyanide specimens were collected before administration of hydroxocobalamin. The threshold for cyanide toxicity was predefined as greater than or equal to 39 micromol/L.
  
  
  RESULTS
  The sample included 69 patients (mean age 49.6 years; 33 men), of whom 39 were comatose. Out-of-hospital deaths were excluded. Fifty of the 69 patients (72%) admitted to the ICU survived after administration of hydroxocobalamin. In the group in which cyanide poisoning was confirmed a posteriori (n=42), 67% (28/42) survived after administration of hydroxocobalamin. The most common adverse events were chromaturia (n=6), pink or red skin discoloration (n=4), hypertension (n=3), erythema (n=2), and increased blood pressure (n=2). No serious adverse events were attributed to hydroxocobalamin. Laboratory tests revealed transient alterations in renal and hepatic function consistent with the critical condition of the patients and mild anemia consistent with progressive hemodilution.
  
  
  CONCLUSIONS
  Empiric administration of hydroxocobalamin was associated with survival among 67% of patients confirmed a posteriori to have had cyanide poisoning. Hydroxocobalamin was well tolerated irrespective of the presence of cyanide poisoning. Hydroxocobalamin appears to be safe for the out-of-hospital treatment of presumptive cyanide poisoning from smoke inhalation.
authors.affiliation: Division of Emergency Medicine, University of Texas Health Science Center, San Antonio, TX, USA.
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Borron
authors.forename: Frédéric J
authors.initials: FJ
authors.lastname: Baud
authors.forename: Patrick
authors.initials: P
authors.lastname: Barriot
authors.forename: Michel
authors.initials: M
authors.lastname: Imbert
authors.forename: Chantal
authors.initials: C
authors.lastname: Bismuth
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000931:Antidotes / Q000009:adverse effects / Q000627:therapeutic use*; D004632:Emergency Medical Services; D005260:Female; D005390:Fires; D006801:Humans; D006856:Hydrogen Cyanide / Q000097:blood / Q000506:poisoning*; D006879:Hydroxocobalamin / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015208:Smoke Inhalation Injury / Q000097:blood / Q000188:drug therapy* / Q000401:mortality; D015996:Survival Rate; D014803:Vitamin B Complex / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000931:Antidotes; D014803:Vitamin B Complex; D006856:Hydrogen Cyanide; D006879:Hydroxocobalamin