Clinical spectrum and outcome of neonatal convulsions.

Abstract

The clinical spectrum and outcome of neonatal convulsions within an obstetric hospital population were reviewed for the 5 years, 1978-82, inclusive. There were 156 convulsing neonates managed at the Mater Mothers Hospital (110 inborn, 46 outborn). The incidence of early neonatal convulsions for inborn babies was 3.0/1000 live births. Antenatal and perinatal risk factors were compared between the 156 convulsing infants and the 36,082 infants born during the same period who did not convulse. The leading risk factors for convulsions were prematurity, intra-uterine growth retardation, low 5 min Apgar score, pre-eclampsia, antepartum haemorrhage, twin pregnancy and breech presentation. The predominant seizure type was tonic in 28.6%, multifocal clonic in 27.2%, subtle in 18.4%, myoclonic in 15.0% and focal clonic in 8.8%. Mortality (31%) and long-term disability (43%) rates were high. Tonic seizures had the highest mortality and morbidity. Throughout the duration of the study period infants received increasingly thorough investigation. Causative factors were determined in 95% of convulsing infants, most frequent being hypoxic-ischaemic encephalopathy (40.3%) and cerebroventricular haemorrhage (30.5%). Follow-up data on 99 of the 107 survivors (93%) revealed severe disability in 25, moderate disability in eight and mild disability in 10. A poor long-term prognosis was associated with prolonged convulsions, tonic and multifocal clonic convulsions, convulsions due to asphyxia and cerebroventricular haemorrhage and an abnormal neurological examination at discharge.