Evolution of the Sarnat exam and association with 2-year outcomes in infants with moderate or severe hypoxic-ischaemic encephalopathy: a secondary analysis of the HEAL Trial

Objective To study the association between the Sarnat exam (SE) performed before and after therapeutic hypothermia (TH) and outcomes at 2 years in infants with moderate or severe hypoxic-ischaemic encephalopathy (HIE). Design Secondary analysis of the High-dose Erythropoietin for Asphyxia and EncephaLopathy Trial. Adjusted ORs (aORs) for death or neurodevelopmental impairment (NDI) based on SE severity category and change in category were constructed, adjusting for sedation at time of exam. Absolute SE Score and its change were compared for association with risk for death or NDI using locally estimated scatterplot smoothing curves. Setting Randomised, double-blinded, placebo-controlled multicentre trial including 17 centres across the USA. Patients 479/500 enrolled neonates who had both a qualifying SE (qSE) before TH and a SE after rewarming (rSE). Interventions Standardised SE was used across sites before and after TH. All providers underwent standardised SE training. Main outcome measures Primary outcome was defined as the composite outcome of death or any NDI at 22–36 months. Results Both qSE and rSE were associated with the primary outcome. Notably, an aOR for primary outcome of 6.2 (95% CI 3.1 to 12.6) and 50.3 (95% CI 13.3 to 190) was seen in those with moderate and severe encephalopathy on rSE, respectively. Persistent or worsened severity on rSE was associated with higher odds for primary outcome compared with those who improved, even when qSE was severe. Conclusion Both rSE and change between qSE and rSE were strongly associated with the odds of death/NDI at 22–36 months in infants with moderate or severe HIE.