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Hydroxyzine premedication--does it provide better anxiolysis than a placebo?
Objectives:
To determine how effective hydroxyzine is compared with a placebo in providing pre-operative anxiolysis in our hospital population, and to assess the anxiolytic effect of our pre-operative visit.
Design:
Double-blind, randomised, prospective, controlled trial. Anxiety levels assessed with visual analogue scales (VAS), by patient and investigator. Haemodynamic parameters measured: heart rate, blood pressure, respiratory rate.
Setting:
Hillbrow Hospital, Johannesburg.
Participants:
Sixty female patients aged 20-60 years, American Society of Anesthesiologists status I-III, scheduled for elective gynaecological surgery under general anaesthesia. The overall participation rate was 100%. All cases were randomly selected.
Intervention:
Hydroxyzine (Aterax) 1-2 mg/kg, or a placebo administered orally as anaesthetic premedication.
Outcome Measures:
Anxiolytic effect of agents and of pre-operative visit. Time interval between premedication and induction of anaesthesia. Blood pressure, heart rate, respiratory rate, other signs of autonomic hyperactivity (restlessness, tremors, sweating).
Results:
A statistically significant reduction in anxiety followed the administration of hydroxyzine (P < 0.05) and the placebo (P < 0.03); however, no statistically or clinically significant difference could be demonstrated between the two agents. No significant anxiolysis occurred following the premedication visit. The average premedication-induction interval was 72 minutes. There were no significant differences in haemodynamic parameters between the two groups.
Conclusions:
Hydroxyzine, in the dose administered and after an appropriate premedication-induction interval, provided no better anxiolysis than a placebo in the pre-operative period. No significant anxiolytic effect was demonstrated by our routine premedication visit.
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