Neonatal death after hypoxic ischaemic encephalopathy: does a postmortem add to the final diagnoses?

Background Case review after fatal perinatal asphyxia may have medicolegal implications. Accurate diagnosis of cause of death is therefore essential. Objective To determine consent rate and utility of autopsy after fatal grade III hypoxic ischaemic encephalopathy (HIE) presumed to be secondary to birth asphyxia. Design A retrospective clinical review from January 1995 to December 2002. Setting Regional tertiary referral neonatal unit, Wellington, New Zealand. Population Inclusion criteria were gestation >= 37 weeks, resuscitation after delivery and clinical course of grade III HIE. Exclusions were a recognised major lethal malformation. Methods Review of clinical records including the autopsy report. Main outcome measures Consent for autopsy, change in diagnosis after autopsy. Results Twenty-three infants died during the time period with a major diagnosis of grade III HIE. Three did not meet inclusion criteria. Of the remaining 20, 11 were female. Median gestation at birth was 40 weeks (range 38-42 weeks) and median birth weight was 3568 g (range 2140-4475 g). In 8/17 of the infants for whom length and head measurements were available, the Ponderal Index suggested intrauterine growth retardation. The 16/20 infants had an autopsy. Four of these were Coroner's cases giving an autopsy rate of 80% with a rate by consent of 60%. In 10 (62.5%) infants, significant new information was added to the clinical diagnoses. Conclusions Neonatal HIE is a symptom rather than a final clinical diagnosis. A full autopsy is required to fully explore the reasons for fatal neonatal HIE and may provide information that is important medicolegally.