INTRAVENTRICULAR HEMORRHAGE AND HIGH-FREQUENCY VENTILATION - A METAANALYSIS OF PROSPECTIVE CLINICAL-TRIALS

Objective. The association between high-frequency ventilation (HFV) an d intraventricular hemorrhage (IVH) and periventricular leukomalacia ( PVL) has been debated. Purpose. To determine if premature neonates tre ated F-vith HFV are at greater risk for developing NH and/or PVL than neonates treated with conventional ventilation, we completed a meta-an alysis of all prospective randomized control trials comparing HFV and conventional ventilation in the management of respiratory distress syn drome. Methods. The meta-analysis included nine studies comparing HFV and conventional ventilation in the management of preterm neonates. To summarize the data, we calculated the difference in absolute risk for IVH and PVL between neonates treated with HFV and those treated with standard ventilation These differences were combined to determine an o verall difference in the absolute risk and its confidence interval We examined the effect of estimated gestational age, birth weight, surfac tant, and age at study entry on the results. Because one trial (HIFI s tudy) was much larger than the other studies, it dominated the analysi s, so rye evaluated the data with and without including data from the HIFI trial. Results. The occurrences of IVH and PVL ranged from 14% to 47% and 5% to 16%, respectively. This variation may be explained by t he difference in the populations of neonates treated. The meta-analysi s showed that use of HFV was associated with an increased risk of PVL (odds ratio = 1.7 with a confidence interval of 1.06 to 2.74), but not IVH or severe (greater than or equal to grade 3) IVH. When the result s of the HIFI study were excluded, there were no differences between H FV and conventional ventilation in the occurrence of IVH or PVL. Concl usions. The association between HFV and adverse neurologic outcomes is primarily influenced by the results of the HIFI trial. Meta-analysis of more recent studies does not confirm the findings of the HIFI trial and suggests that HFV is not associated with increased occurrence of IVH or PVL.