[Effect of etomidate and thiopental on the onset of rocuronium action].
OBJECTIVE
Differences in the hemodynamic effects of induction agents may cause them to affect the onset of action of rocuronium differently.


OBJECTIVE
To compare the onset of action of rocuronium after induction with etomidate and thiopental.


METHODS
Forty adult ASA I patients received 3 micrograms.kg-1. Three minutes later anesthesia was induced randomly with either 5 mg.kg-1 of thiopental (group I, n = 20) or 0.3 mg.kg-1 of etomidate (group II, n = 20). Rocuronium 0.6 mg.kg-1 was administered over 5 s. Baseline blood pressure and heart rate were measured just before delivery of rocuronium and just before intubation. Onset of action was defined as the time from injection of rocuronium until achievement of a blockade > or = 95% of the first electromyographic response in a trian-of-four stimulus of the short adductor of the thumb. We also studied intubation conditions.


RESULTS
Etomidate was associated with a smaller decrease in systolic arterial pressure than was thiopental. Onset of action was 81 +/- 29 s in group I versus 72 +/- 23 s in group II (NS). Similar intubation conditions were observed in both groups.


CONCLUSIONS
These results suggest that the induction drug does not affect rocuronium's onset of action.
Muñoz Letelier
H
H
Departamento de Anestesiología, Escuela de Medicina, Universidad Católica de Chile, Santiago, Chile. hmunoz@med.puc.cl
González Arellano
A
A
Dagnino Sepúlveda
J
J
González Sotomayor
J
J
D000328:Adult; D000732:Androstanols / Q000494:pharmacology*; D018686:Anesthetics, Intravenous / Q000494:pharmacology*; D004347:Drug Interactions; D004576:Electromyography; D005045:Etomidate / Q000494:pharmacology*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D003473:Neuromuscular Nondepolarizing Agents / Q000494:pharmacology*; D000077123:Rocuronium; D013874:Thiopental / Q000494:pharmacology*; D013997:Time Factors
D000732:Androstanols; D018686:Anesthetics, Intravenous; D006993:Hypnotics and Sedatives; D003473:Neuromuscular Nondepolarizing Agents; D013874:Thiopental; D000077123:Rocuronium; D005045:Etomidate
Efecto del etomidato y del tiopental sobre el comienzo de acción del rocuronio.