Effect of Fentanyl and Nalbuphine for Prevention of Etomidate-Induced Myoclonus.

BACKGROUND

Etomidate is a potent intravenous inducing agent with known undesirable side effects such as myoclonus and pain on injection in nonpremedicated patients.

AIMS

The aim of this study is to compare the effect of fentanyl and nalbuphine in the prevention of etomidate-induced myoclonus.

SETTINGS AND DESIGN

Randomized double-blind, placebo-controlled, and prospective comparative study.

MATERIALS AND METHODS

A total of 120 patients were randomly allocated to one of the three groups containing 40 patients each for intravenous administration of fentanyl 2 μg/kg diluted in 10 mL normal saline (NS) (Group 1), nalbuphine 0.3 mg/kg diluted in 10 mL NS (Group 2), and only 10 mL NS (Group 3) over 10 min. All groups subsequently received 0.3 mg/kg etomidate by intravenous bolus injection over 15-20 s and were assessed for the severity of pain using Grade IV pain scale and observed for myoclonus for 2 min and graded according to clinical severity. Serum creatinine phosphokinase (CPK) levels were obtained prior and postetomidate injection.

STATISTICAL ANALYSIS

Statistical analysis was performed by the SPSS program version 17.0 for Windows. Tests used are Shaipro-Wilk test, ANOVA, Tukey's multiple comparison test, Tamhane's T2, and the Chi-square test. For all statistical tests, < 0.05 was considered statistically significant with 5% level of significance (α).

RESULTS

The incidence of myoclonus in Group 1 and 2 was 52.5% and 17.5%, respectively, whereas it was 92.45% in Group 3. There was no pain observed in 70%, 92.5%, and 50% of patients in Group 1, 2, and 3, respectively. There was a statistically significant difference in mean CPK level after induction among three groups ( < 0.001).

CONCLUSION

Nalbuphine is more effective than fentanyl in the prevention of etomidate-induced myoclonus and pain with the minimum rise in CPK levels.