[Effect of etomidate and thiopental on the onset of rocuronium action]. / Efecto del etomidato y del tiopental sobre el comienzo de acción del rocuronio.

HYPOTHESIS: Differences in the hemodynamic effects of induction agents may cause them to affect the onset of action of rocuronium differently. OBJECTIVES: To compare the onset of action of rocuronium after induction with etomidate and thiopental. PATIENTS AND 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.

Pharmacokinetics of ketorolac in children after abdominal surgery.

The pharmacokinetics of 2 doses of intravenous ketorolac (0.5 and 0.9 mg x kg-1) were studied in 14 children (age 2-8 years). A single dose of the drug was injected into the dorsum vein of one hand. Blood samples were collected at regular time intervals for 6 hours. Serum ketorolac concentrations were assayed using a high pressure liquid chromatography method. Pharmacokinetic values were estimated by a nonlinear computer program. The distribution volume (Vdarea), the total clearance (Cltotal), and elimination half-life (t1/2 beta) were similar in both groups of children who either received 0.5 or 0.9 mg x kg-1 of ketorolac. The estimated geometric mean Vdarea, Cltotal, and t1/2 beta ratios (95% CI in parentheses) for 0.9 mg x kg-1:0.5 mg x kg-1 were 1.24 (0.82, 1.50), 1.14 (0.88, 1.23), and 1.083 (0.40, 1.81), respectively. The pharmacokinetic parameters found in this study are different from those found by other authors in adult subjects.