Propofol versus midazolam for premedication: a placebo‑controlled, randomized double‑blinded study

Area of Science:

• Anesthesiology
• Pharmacology

Background:

• Subhypnotic doses of propofol may be advantageous for premedication compared to midazolam.
• Acute anxiety reduction prior to anesthesia induction is a key concern in outpatient surgery.

Purpose of the Study:

• To test if a 20 mg IV dose of propofol is more effective than a 2 mg IV dose of midazolam for reducing acute anxiety before anesthesia induction.
• To compare the effects of propofol, midazolam, and saline on anxiety, sedation, and recall.

Main Methods:

• 120 orthopedic surgery outpatients were randomized into three groups: saline (control), propofol (20 mg IV), or midazolam (2 mg IV).
• Anxiety and sedation levels were assessed using 11-point verbal rating scales before medication, upon OR arrival (~5 min post-medication), and at recovery discharge.
• Recall of two presented pictures was assessed at recovery discharge.

Main Results:

• Both propofol and midazolam significantly increased sedation upon OR arrival compared to saline (p<0.001).
• Propofol (20 mg IV) and midazolam (2 mg IV) were equally effective in reducing preinduction anxiety compared to saline.
• Propofol caused more injection pain, and midazolam significantly reduced recall of a picture shown in the OR.

Conclusions:

• A 20 mg IV dose of propofol is as effective as a 2 mg IV dose of midazolam in reducing acute anxiety approximately 5 minutes prior to entering the operating room.
• Both agents increase sedation, but propofol is associated with injection pain and midazolam with impaired recall.