THE TIMING OF INTRAVENTRICULAR HAEMORRHAGE

The aetiology of IVH is controversial. Present techniques concerning its timing rely either on clinical observations - namely the occurence of convulsions or collapse, or on sophisticated radiochemical methods. We have continuously measured intra-arterial blood pressure, and central and peripheral temperatures in low birthweight infants at risk of IVH in an attempt to identify factors either causative or indicative of IVH. Since we give regular small transfusions of fresh adult blood to low birthweight infants, frequent estimates of the HbA/HbF ratio /Kleihauer technique/ provide a time-base for comparison with post-mortem samples of ventricular clot. When fresh blood containing HbF is allowed to clot, the HbA/HbF ratio is unaltered. With this technique, we have been able to date ventricular haemorrhage. This seems to have occured before the emergence of overt clinical signs. Differences in patterns of monitored data between these infants and ones who had not developed an IVH will be illustrated.