[Optimizing anesthesiologic premedication with reference to biopsychological theories. Exemplified by the effect of dipotassium clorazepate and zolpidem in combination with promethazine]

Abstract

The following double-blind randomized placebo-controlled study dealt with three questions: 1. Are differentiated psychometric test systems suitable measuring emotions before anaesthesia? 2. What are the effects of different doses of zolpidem (8.03 mg vs. 16.06 mg) compared with dipotassiumclorazepat (10 mg vs. 20 mg) on emotions in premedication? 3. Is the combination with Promethazin suggestive?

Method: 320 patients were randomly assigned to different regimes of preanaesthetic medication. As primary premedication they received either zolpidem 8.03 mg or zolpidem 16.06 mg or dipotassium clorazepate 10 mg or dipotassium clorazepate 20 mg or placebo. The secondary premedication was either promethazine 50 mg or placebo. The tablets/dragees were given in the evening before surgery (09.00 p.m.-10.00 p.m.). Every cell of the 5 x 2-factorial design contained 16 men and 16 women. Emotions were measured by a multidimensional rating scale, comprising the aspects elated mood, anxiety, hostility, deactivation, vigilance and introversion. In addition, somatic symptoms and the quality of sleep were measured. Statistics were performed using multivariate analysis of variance.

Results: No differing effects of zolpidem and dipotassium clorazepate on preoperative mood were found. There was also no difference compared with placebo. Compared with placebo, promethazin leads to greater deactivation. Specific emotions were not affected. In somatic aspects there was a greater amount of cholinergic effects under promethazine, which was mainly expressed by a higher intensity of a dry mouth and weakness in general. Compared with placebo all of the tested drugs led to a better quality of sleep.

Conclusions: Using multidimensional rating scales and considering emotions as a multifactorial construct, the study shows no different effects of benzodiazepines or benzodiazepin-like drugs on preoperative mood. No differences were also found on comparing these drugs with placebo. However, a better quality of sleep was seen under zolpidem and dipotassium clorazepate compared with placebo. The study shows that a combination with promethazine is recommended, because promethazine has a selective deactivating effect. The study stresses the significance of multidimensional rating scales for the measurement of emotions before anaesthesia.