[Diagnostic possibilities and limits of 4-electrode rheoencephalography in premature infants with risk of brain damage].

Diagnostic value of cerebral electrical impedance for recognizing the risk of cerebral damage was analysed in 63 premature infants with postnatal respiratory disturbance during the first 4 weeks of life. Relationship between clinical risk factors like gestational age, Apgar scores, blood gas values on the one hand and impedance parameter of pulse volume, flow velocity and periphereal vascular resistance on the other were studied by means of correlation as well as variance analysis. Decrease of gestational age, Apgar score and increasing severity of respiratory disturbance cause statistically significant lowering of impedance parameters indicating reduction of volume, flow velocity and periphereal resistance in cerebral circulation by extreme immaturity, serious asphyxia as well as idiopathic respiratory distress syndrome. On contrast no statistically significant difference could be found between infants with and without intraventricular haemorrhages. However, significant differences were seen between group of patients only. Because of intercorrelation of risk factors and distinct variance no critical level of impedance parameters could be defined for the individual patient.