Original articleOutcomes of hypoxic ischaemic encephalopathy treated with therapeutic hypothermia using cool gel packs – Experience from Western Australia
Introduction
Moderate-to-severe hypoxic ischaemic encephalopathy (HIE) occurs at an approximate rate of 1–2 per 1000 live births1, 2 and carries a high risk of mortality and long term disability.3, 4, 5 Systematic reviews of randomized trials have shown that therapeutic hypothermia decreases mortality and neurodevelopmental disability in infants with moderate to severe HIE.1, 6, 7, 8 The fetal and newborn committee of the Canadian Pediatric Society recommends the use of whole body cooling (rectal temperature of 34 ± 0.5 °C) or selective head cooling initiated as soon as possible within the first 6 h of life in infants with moderate HIE who are ≥36 weeks' gestational age.9Our neonatal units have been offering therapeutic hypothermia since January 2008. We conducted this retrospective study to evaluate the long term outcomes of neonates who underwent therapeutic cooling for hypoxic ischaemic encephalopathy.
Section snippets
Patient population
All infants who underwent therapeutic hypothermia for HIE between 1st January 2008 and 30th June 2010 were identified from the neonatal database. Relevant information was obtained by reviewing the medical records of patients, the laboratory database and the neonatal follow up program database.
Clinical protocol of cooling
The infants were eligible for cooling if they met the following criteria:-
- 1.
≥35 weeks gestational age
- 2.
<6 h of age
- 3.
evidence of asphyxia as defined by at least 2 of the following 4 criteria –
- a.
Apgar Score <6 at
- a.
Results
68 infants were treated with therapeutic hypothermia during the study period. Three were excluded: 1 because of mitochondrial cytopathy, second one had a massive intra abdominal tumour requiring chemotherapy in the 1st few days of life and the 3rd infant had congenital hypopituitarism and septo-optic dysplasia. The remaining 65 were included in the study.
The maternal and obstetric details are given in Table 1. In nineteen cases there was a clear sentinel perinatal event: seven had shoulder
Discussion
We have reported on the long term outcomes of 65 neonates with HIE who were managed using the manual method of cool gel packs. To our knowledge it is the second study reporting on the long term outcomes of using cool gel packs outside clinical trial set up. The other study was by Koshy et al. from India14 who reported neurodevelopmental outcomes at 18–24 months of age in infants who were cooled using cool gel packs. Only 3/15 (20%) had an adverse outcome (2 death and 1 disability) in their
Conclusions
Neonates undergoing therapeutic hypothermia with cool gel packs had both good survival rates and long term neurodevelopmental outcomes. These results were similar to international randomized trials.
References (30)
Hypothermia: a systematic review and meta-analysis of clinical trials
Semin Fetal Neonatal Med
(Oct 2010)- et al.
Threshold of metabolic acidosis associated with newborn complications
Am J Obstetr Gynecol
(Dec 1997) - et al.
Long-term neurodevelopmental outcomes after intrauterine and neonatal insults: a systematic review
Lancet
(Feb 4 2012) - et al.
Prediction of neurodevelopmental outcome in term neonates with hypoxic-ischemic encephalopathy
Eur J Paediatr Neurol
(May 2013) - et al.
Selective head cooling with mild systemic hypothermia after neonatal encephalopathy: multicentre randomised trial
Lancet
(Feb 19–25 2005) - et al.
Performance of 2-year-old children after early surgery for congenital heart disease on the Bayley scales of infant and toddler development, third edition
Early Hum Dev
(2012 Aug) - et al.
School performance of survivors of neonatal encephalopathy associated with birth asphyxia at term
J Pediatr
(1989 May) - et al.
A review of developmental outcomes of term infants with post-asphyxia neonatal encephalopathy. European journal of paediatric neurology
EJPN Off J Eur Paediatr Neurol Soc
(May 2009) - et al.
Short-term outcomes of newborns with perinatal acidemia who are not eligible for systemic hypothermia therapy
J Pediatr
(Jan 2013) - et al.
Long-term follow-up of term neonates with perinatal asphyxia
Clin Perinatol
(Jun 1993)