A study published in JAMA Pediatrics found that therapeutic hypothermia, a treatment that lowers body temperature to around 92°F, does not benefit preterm infants (33–35 weeks gestation) with hypoxic-ischemic encephalopathy (HIE). Unlike in term and near-term infants (≥36 weeks), where cooling therapy reduces the risk of death or disability, preterm infants did not show improved outcomes.
When inadequate blood flows to the infant's brain due to hypoxic-ischemic events during the prenatal, intrapartum, or post-natal period, it leads to cerebral injury often called Hypoxic Ischemic Encephalopathy.1 Preterm infants have more incidence of neonatal brain injury, with harmful effects on motor, cognitive, behavioural, social, attentional, and sensory outcomes.2 HIE in preterm infants can result from complications like umbilical cord compression or uterine rupture. Despite the increasing use of cooling therapy in this population, the study highlights its potential harm.
The study, led by Roger G. Faix, M.D., from the University of Utah, included 188 preterm infants with HIE born between 2015 and 2020 across 19 newborn research centers. Among them, 88 were randomly assigned to cooling therapy, while 80 received standard care with normal body temperature. At 18–22 months of age, researchers evaluated the occurrence of death and moderate to severe disability rates in these children.
The results showed that 35% of infants who received cooling therapy had died or had a disability, compared to 29% of newborns who received standard care.3 More alarmingly, the mortality rate was 20% in the cooling group versus 12% in the standard care group. This translates to a 74% higher risk of death or disability and an 87% higher risk of death for preterm infants undergoing cooling therapy.
This study provides critical insight into the risks of therapeutic hypothermia for preterm infants with HIE. While cooling therapy is well-established for term and near-term infants, its increasing use in preterm infants despite limited evidence highlights the need for caution. Clinicians should reconsider using therapeutic hypothermia for preterm infants with HIE. Further research is needed to explore alternative neuroprotective strategies tailored to this vulnerable group.
References:
- Long M, Brandon DH. Induced hypothermia for neonates with hypoxic-ischemic encephalopathy. Journal of Obstetrics Gynecology Neonatal Nursing. 2007;36:293–298. doi: 10.1111/j.1552-6909.2007.00150.x.
- Moore T, Hennessy EM, Myles J, Johnson SJ, Draper ES, Costeloe KL, et al. Neurological and developmental outcome in extremely preterm children born in England in 1995 and 2006: the EPICure studies. BMJ (2012) 345:e7961. 10.1136/bmj.e7961
- Roger G. Faix et al, Whole-Body Hypothermia for Neonatal Encephalopathy in Preterm Infants 33 to 35 Weeks' Gestation, JAMA Pediatrics (2025)
Read more...