344 The Value of Diffusion-Weighted Magnetic Resonance Imaging, Ultrasonography and Electroencepahlography for Early Diagnosis of Neonatal Encephalopathy

Abstract

NICHD NEONATAL RESEARCH NETWORK (USA)Background: Post-asphyxial hypothermia is protective in experimental animals; however, there have been no RCT evaluating safety and effectiveness of whole body hypothermia in term infants with HIE.Objective: To assess safety and effectiveness of whole body hypothermia in term infants with moderate and severe HIE.Design/Methods: A RCT was conducted of infants 36 weeks GA admitted 6 h of age with either a) a cord or first (Ͻ1 hour) pH Ͻ7.0 or BD Ͼ16 mEq/dl or b) a perinatal event and need for resuscitation, AND evidence of moderate or severe HIE by a certified examiner. Infants were randomized to normothermia (NORMO) or whole body cooling to 33.5 C esophageal (HYPO) for 72 h followed by rewarming by on site-research personnel using the Cincinnati Sub-Zero system. Primary outcome was death or disability at 18 mos: severe disability defined as ANY: Bayley MDIϽ70, Gross Motor Function (GMF) level 3-5, hearing impairment requiring aids, or blindness or moderate disability defined as MDI 85-70 AND either GMF 2, hearing impairment with no amplification or seizure disorder.Results: Of 798 screened infants, 239 were eligible, and 208 were randomized; 102 to HYPO and 106 to NORMO. Target temperature was achieved in HYPO within 90 min and remained constant throughout 72 h. Adverse events were similar among HYPO infants (nϭ19) and NORMO (nϭ15), pϭ0.38. At 18 mos, primary outcome data were available for 204 of the 208 infants. Death or moderate/severe disability occurred in 45 (45%) infants in HYPO and 64 (62%) in NORMO: Risk Ratio (RR) (95%CI) 0.72 (0.55-0.93) with # needed treat (NNT)ϭ6. The risk of death was 24% in HYPO and 36% in NORMO, RR 0.66 (0.43-1.01). The risk of death or disability after moderate HIE was RR 0.67 (0.44 -1.03) and after severe HIE was 0.82 (0.64 -1.06). For HYPO and NORMO respectively, the risks of disabling CP was 19.7% and 28.6%, RR 0.69 (0.38 -1.26), blindness was 5.5% and 14.3%, RR 0.38(0.12-1.19) and hearing impairment requiring aids was 4.0% and 6.3%, RR 0.64 (0.15-2.75). Conclusions:We have demonstrated the effectiveness and safety of whole body hypothermia in term infants with moderate and severe HIE, defined by rigorous criteria, using certified examiners and trained personnel to implement and monitor the intervention and outcome.