Research highlights rewarming stage of cooling therapy for brain injured babies

Babies deprived of oxygen during birth typically undergo cooling therapy in hospital to protect their brains and to improve their neurodevelopmental outcomes.

Many will have suffered Hypoxic-Ischaemic Encephalopathy (HIE) where there is a lack of oxygen and blood flow to the brain before, during, or shortly after labour. This is also referred to as 'asphyxia' or 'birth asphyxia'.

Often there has been negligent delay in delivering these babies where signs of distress are not monitored or recognised, leading to birth injury. Such injuries can also occur following uterine rupture, placental abruption, shoulder dystocia and umbilical cord prolapse.

Cooling therapy, or therapeutic hypothermia, is where the baby’s temperature is lowered for 72 hours using cooling mats or jackets. Cooling is started as soon as possible, and within the first 5-6 hours of the HIE event. Cooling has been shown to limit the extent of injury to the brain.

Now, a team of researchers led by Professor of Paediatrics and Psychiatry at UT Southwestern, a leading medical centre in the US, has specifically looked at the rewarming process that babies go through following cooling, concerned that there is a significantly elevated risk of seizures during rewarming that often go unnoticed but which can cause long-term harm.

What they found was that during cooling, babies with HIE regularly experience symptomless seizures - neurological events that can further damage the brain – meaning electroencephalographic (EEG) monitoring has become a usual part of the hypothermia protocol. However, babies are not typically monitored during the rewarming stage, during which the temperature of the jacket is increased by 0.5°C per hour until the baby reaches normal body temperature.

In their study of 120 babies, they found that rewarming increased the likelihood of seizures about three-fold. And babies who had seizures during rewarming were about twice as likely to die or have a neurological disability by age two, compared with those who didn't have seizures during rewarming.

The ultimate problem is, however, that it is not known how to prevent these seizures from occurring, although treating the seizures when they do occur can help prevent further brain damage.

The outcome of the study, then, is to encourage hospitals to monitor during cooling and rewarming to help protect young brains from further insults while they heal and to give them the best possible chance of positive outcomes.

Read about our cerebral palsy claims and birth injury claims.