Prospective Research in Infants With Mild Encephalopathy
Prospective Research in Infants With Mild Encephalopathy: the PRIME Study.
A multicenter observational pilot study will be conducted to determine the natural history
of infants with early diagnosis (≤ 6 hrs of age) of mild neonatal encephalopathy (NE) who
are not qualified for therapeutic hypothermia. The intervention includes: neurologic
examination by using modified Sarnat score at ≤ 6 hrs of age, 24 hrs and before discharge
home, amplitude-integrated electroencephalography (aEEG) at 6 ± 3 hrs of age, brain MRI at
before discharge home to 30 days of age and follow-up at 18-22 months of age. Primary
outcome is the percentage of mild NE infants with evidence of brain injury defined by the
presence of at least 1 abnormality of brain MRI, aEEG or neurologic examination in the
neonatal period. Secondary outcome is the percentage of brain MRI, aEEG and neurological
exam abnormalities, seizure, length of hospital stay, need of gavage feeds or gastrostomy at
discharge home, death and long-term outcome.
Globally, an estimated 1.8 to 7.7 infants per 1000 live term births suffer from perinatal
asphyxia, which remains an important cause of neonatal encephalopathy (NE) and
neurodevelopmental impairment. Over the last six years, several randomized control trials
have demonstrated that prolonged and moderate therapeutic hypothermia (TH) reduces the rate
of death or disability at 18 months of age among infants who survived. In these trials,
infants were eligible if there was evidence of perinatal hypoxia-ischemia and a moderate or
severe degree of encephalopathy on neurological evaluation performed at ≤ 6 hrs of age.
However, it has been recognized that the level of NE may change over time. Preliminary and
unpublished observations from our group indicated that some infants who were not classified
as moderate or severe NE had neurological abnormalities at discharge or evidence of brain
injury on MRI performed during the neonatal period. Unfortunately, precise data on the
outcomes of this specific population is not clear. Since TH is not offered to this
population, the outcomes of infants that do not qualify for TH based on neurological
evaluation performed ≤ 6 hrs of life requires a more precise investigation.
- Infants with birth weight > or = 1800g and gestational age > or = 36 weeks AND
- Admission to neonatal intensive care unit (NICU) for possible hypothermia at < or =
6hr of life
- Infants with normal neurological evaluation
- Major congenital abnormalities
- Refusal of informed consent
- Infants who receive passive or active cooling prior to the NICU admission
- Infants that develop seizures or moderate/severe NE within the first 24 hr of life
and are initiated on therapeutic hypothermia after 6 hr of life.