[Modulation of the stress response in children in the preoperative preparation]

Abstract

Anxiolysis with drugs and psychoprophylaxis are both recognised methods of preoperative preparation. The beneficial effects of anxiolytics, however, appear to be difficult to prove. In this study a comparison was made of heart rate (HR), blood pressure (BP), and norepinephrine, epinephrine, and cortisol levels. In group I 19 children received only psychological treatment, while in group II 21 children received 0.2 mg/kg midazolam orally. Measuring points were directly before medication, 30 min afterward, and at induction of anaesthesia. During the observation period the patients (5-10 years old) remained calm. At the beginning of the study the parameters of all patients were within a normal range; 30 min after premedication the HR and BP were significantly higher in group I than in group II. In contrast to group I, epinephrine levels in group II were lower at the beginning of anaesthesia than before premedication. In both groups, norepinephrine levels were the same at induction of anaesthesia as before premedication. Cortisol decreased only in patients who received midazolam. HR, BP, as well as humoral stress parameters indicate that midazolam in a dose of 0.2 mg/kg orally is sufficient to reduce preoperative stress in children.