[Thiocyanate toxicity arising from prolonged use of sodium nitroprusside in severe heart failure].
OBJECTIVE
To evaluate the toxicity of thiocyanate induced by the infusion of sodium nitroprusside in patients with severe congestive failure.


METHODS
We studied 23 patients with congestive heart failure, in class IV (NYHA) under continuous infusion of sodium nitroprusside with doses varying between 0.5 and 5.5 micrograms/kg/min. Clinical evaluation, thiocyanate serum dosage and laboratorial evaluation of renal, hepatic and pulmonary functions were done.


RESULTS
Seventeen patients (74%) presented toxic levels of thiocyanate (over 10 micrograms/ml), with the average of 29.9 +/- 4.4 micrograms/ml. Only renal function was related to the presence of intoxication. Clinical evaluation was not accurate to diagnose the thiocyanate toxicity in the patients.


CONCLUSIONS
Sodium nitroprusside is potentially toxic, especially when the renal function is abnormal. Thiocyanate dosage is useful in diagnosing nitroprusside induced toxicity and then it contributes to an adequate treatment and prevention of clinical toxicity.
Instituto do Coração, Hospital das Clínicas, FMUSP.
S G
SG
Lage
R T
RT
Carvalho
L
L
Kopel
M C
MC
Monachini
G
G
Bellotti
F
F
Pileggi
D000328:Adult; D005260:Female; D006333:Heart Failure / Q000097:blood*; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009599:Nitroprusside / Q000008:administration & dosage* / Q000009:adverse effects / Q000378:metabolism; D012189:Retrospective Studies; D013861:Thiocyanates / Q000506:poisoning*; D013997:Time Factors
D013861:Thiocyanates; D009599:Nitroprusside
Toxicidade pelo tiocianato decorrente do uso prolongado de nitroprussiato de sódio na insuficiência cardíaca grave.