[Effects of midazolam premedication on induction doses of propofol and hemodynamic changes during tumor patient...

Midazolam is a useful drug used preoperatively because it can produce anxiolysis and sedation. This study compared the propofol requirements and haemodynamic effects during anaesthetic induction using propofol with premedication of midazolam or luminal.

Thirty patients (aged 20-65, ASA I-II) undergoing tumor surgery were randomly assigned into 2 groups (group M and group L): group M, receiving 0.5 mg atropine and 0.05 mg/kg midazolam; group L, receiving atropine and 2 mg/kg phenobarbital sodium 30 min before induction as premedication. Anesthesia was induced with propofol at the rate of 30 mg.kg-1.h-1 to achieve enough depth of anesthesia to intubate. Induction time, total propofol dosage, blood pressure, heart rate were recorded before and after induction, and after intubation. Awaken time was also recorded.

The time of induction and the propofol dosage in group M (2.8 +/- 0.37 min and 79.9 +/- 15.3 mg) were significantly (P < 0.05) less than that in group L (3.3 +/- 0.54 min and 98.9 +/- 17.4 mg). Blood pressure was unchanged in M group after propofol induction and after the intubation. Heart rate change was much less in group M (P < 0.05).

The results indicate that midazolam compered to phenobarbital sodium as premedication could reduce the usage of propofol, and also provide stable cardiovascular state during propofol induction.