PREMEDICATION WITH ORAL MIDAZOLAM IN CHILDREN - AN ASSESSMENT OF PSYCHOMOTOR FUNCTION, ANXIOLYSIS, SEDATION AND PHARMACOKINETICS

We studied 30 children, aged 4 to 12 years, undergoing elective circum cision, premedicated with midazolam 0.5 mg.kg-1 and atropine 0.02 mg.k g-1 by mouth. A modified postbox test and the coding component of the Wechsler intelligence scale (WISC-R) was used to assess the preoperati ve effect of premedication on psychomotor function. Mood and sedation were also scored and related to serum midazolam concentrations. The ch ildren showed a significant decline in psychomotor performance 30 and 60 minutes after premedication when compared with their best unmedicat ed performance recorded the previous evening. This decline in psychomo tor performance was only weakly associated with serum midazolam concen trations (r = 0.1). The postbox toy ratio is a suitable measurement of psychomotor performance in children because of its simplicity and eas e of use in the clinical environment, although it may suffer the ''tes t-retest'' limitations of similar types of assessment. The sedative an d anxiolytic effects of midazolam provide a quiet environment for a sm ooth induction of anaesthesia.