Perinatal asphyxia at Port Moresby General Hospital: a study of incidence, risk factors and outcome.

We investigated the incidence and outcome of perinatal asphyxia (PA) at Port Moresby General Hospital by a retrospective chart review and prospective collection of data, spanning a total of 2.5 years. 125 babies weighing more than 2000 g at birth with a gestation of 34 weeks or more and with no obvious congenital abnormalities were diagnosed to have PA. During the same time period 22,700 liveborn babies were delivered, a PA incidence of 5.5/1000 livebirths. There was a 31% mortality and considerable morbidity. Hospital records for 114 affected babies and 115 controls (the next baby born by normal delivery) were compared. Significant risk factors for PA were: previous stillbirth or neonatal death, fetal heart rate abnormalities, membranes ruptured for more than 12 hours prior to delivery, meconium staining, antepartum haemorrhage, maternal fever, prolonged first and second stages of labour, preterm or post-term delivery and operative delivery. In only 73 affected babies was the 5-minute Apgar score recorded as 6 or less. All 34 of the babies with grade 3 hypoxic ischaemic encephalopathy (HIE) either died (30) or had serious neurological impairment. The treatment of affected babies remains largely supportive and some causes of PA are currently unavoidable. It is, however, widely accepted that some cases of perinatal asphyxia may be prevented by the delivery of high-risk pregnancies in obstetric facilities with appropriate intervention and by good neonatal resuscitation. Sophisticated or expensive equipment is not a necessity.