European Journal of Biomedical and Pharmaceutical Sciences

ANESTHESIA INDUCTION WITH MIDAZOLAM AND PROPOFOL AFTER MIDAZOLAM PREMEDICATION: DOSE FINDING OF THE COMBINATION

Tomoki Nishiyama*

ABSTRACT

This study was performed to investigate optimal doses of midazolam and propofol in combination for induction of anesthesia. One hundred and eighty patients aged 30 to 70 years for general anesthesia were equally divided into 6 groups. Midazolam 0.05 mg/kg was intramuscularly administered 15 minutes before entering the operating room. Anesthesia was induced with midazolam 0.025, 0.05, 0.075, 0.1, 0.15, or 0.20 mg/kg with vecuronium 0.01 mg/kg, and 2 minutes later, propofol infusion was started at 200 mg/min. Eyelash reflex and verbal response were checked every 10 seconds and when both disappeared, propofol infusion was stopped, then vecuronium 0.14 mg/kg was administered for oro-tracheal intubation. The total dose of propofol of the patients whose systolic blood pressure one minute after intubation was within ± 20% of pre-induction value was judged as an adequate dose. The dose of propofol judged as adequate was 2.46±0.59, 2.12±0.47, 1.85±0.45, 1.36±0.42, 1.22±0.53, or 0.82±0.53 mg/kg at midazolam 0.025、0.05、0.075、0.1、0.15、or 0.2 mg/kg, respectively. After premedication with intramuscular midazolam 0.05 mg/kg, midazolam 0.025, 0.05, 0.075, 0.1, 0.15, or 0.2 mg/kg and propofol 2.46 ± 0.59, 2.12 ± 0.47, 1.85 ±0.45, 1.36 ± 0.42, 1.22 ± 0.53, or 0.82 ± 0.53 mg/kg, respectively could give stable hemodynamics at induction of anesthesia.

Keywords: anesthesia induction, propofol, midazolam.