Studies on the side effects of diazepam on the particularly vulnerable brain of preterm infants have not been done so far. We studied changes of blood flow velocity in the anterior, basilar and internal carotid artery by Doppler technique in 11 preterm infants less than 1,500 g who were given 0.5 mg/kg i.v. diazepam. The flow velocities in the internal carotid and basilar artery did not change significantly and values for carbon dioxide tension, mean arterial blood pressure and HF remained stable. There was a marked increase of flow velocity in the anterior cerebral artery. We conclude that diazepam in this dosage does not cause dangerous haemodynamic changes in the premature brain.

Aim of the study was the assessment of possible side effects of analgesia with pethidine on the intracerebral circulation of very immature preterm infants. For this purpose the blood flow velocity in the internal carotid artery, basilar cerebral artery and the anterior cerebral artery was measured by pulsed Dopplersonography before and 5-10 min after i.v. injection of 1.0 mg/kg pethioine on 10 preterm infants with a gestational age of 24-30 weeks. Furthermore values for the parameter mean arterial blood pressure, heart frequency and tcpCO2 were obtained. None of the measured parameters showed a significant difference with the i.v. bolus injection of pethidine. As even very immature preterm infants do feel pain and can show potential dangerous physiological pain reactions and as this study proves the tolerance of the drug, analgesia with morphine derivates is recommended.

Aim of the study was the assessment of possible side effects of analgesia with pethidine on the intracerebral circulation of very immature preterm infants. For this purpose the blood flow velocity in the internal carotid artery, basilar cerebral artery and the anterior cerebral artery was measured by pulsed Dopplersonography before and 5-10 min after i.v. injection of 1.0 mg/kg pethidine on 10 preterm infants with a gestational age of 24-30 weeks. Furthermore values for the parameter mean arterial blood pressure, heart frequency and tcpCO2 were obtained. None of the measured parameters showed a significant difference with the i.v. bolus injection of pethidine. As even very immature preterm infants do feel pain and can show potential dangerous physiological pain reactions and as this study proves the tolerance of the drug, analgesia with morphine derivates is recommended.

In very premature ventilated infants (GA 25-30 weeks, BW 575-1420 g) values for heart frequency, mean arterial blood pressure and pCO2 were obtained, and also Doppler-sonographic measurements of the right internal carotid artery were performed to assess cerebral haemodynamics, before and 5-10 min after the intravenous injection of 20 mg/kg phenobarbitone (study I/n = 10) or 5 mg/kg phenobarbitone (study II/n = 10). There were no significant changes in any of these parameters. Therefore phenobarbitone does not have seem to have any significant effect on cerebral haemodynamics up to a dosage of 20 mg/kg, so that there is no apparent effect on the risk of cerebral haemorrhage. On the other hand this study confirms that phenobarbitone can be used in very low birth weight preterm infants with this dosage without causing any substantial haemodynamic risk.