Cooling for babies with HIE birth injuries

If your baby needs neonatal intensive care after a hypoxic birth injury, their medical team may recommend that they are treated with cooling. You may be advised that this treatment must take place urgently or that your baby is being transferred to a more specialist neonatal intensive care unit for the cooling to take place.

It can be hard to make important decisions for your new baby so soon after a difficult or traumatic birth. Knowing that your baby needs specialist or intensive neonatal treatment can be frightening. You may feel overwhelmed as you try to understand what has happened and what the birth injury and cooling treatment will mean for your baby.

On this page you will find the answers to many of the questions that families have about cooling: what it is, what will happen, and how it helps.

Our birth injury solicitors have helped countless families of children born with HIE brain injury to understand how their injury occurred and to claim the compensation and support that they need for their child. If your baby needs cooling or was cooled after a difficult or delayed delivery, we can help you answer these questions with advice from trusted independent medical experts, and secure the compensation and practical support that your baby deserves. If you would like to find out more about why your baby needed cooling, and what that means for your baby and your family, contact us to talk, free and confidentially, to one of our experienced birth injury solicitors.

What is cooling?

Cooling (also known as therapeutic hypothermia) is a treatment that is given to newborn babies who are born with moderate or severe HIE brain injury.

If your baby needs cooling, you may have already heard the terms ‘HIE’ or ‘hypoxic birth injury’. HIE is short for hypoxic ischaemic encephalopathy, which means injury to the brain caused by lack of oxygen, and these terms are used interchangeably to describe the brain injury suffered by babies who are deprived of oxygen around the time of birth.

Babies born with HIE birth injury can develop severe physical and cognitive (thinking) disability, which may affect their ability to walk and talk, feed and look after themselves, or study, work and live independently in future. Hypoxic brain injury is irreversible and cannot be cured but, for some babies, neonatal treatment with cooling can reduce their long-term physical disability.

Therapeutic hypothermia or cooling lowers the baby’s brain and body temperature to a level which slows down the rate of damage to the brain after a prolonged or acute (sudden) shortage of oxygen. This reduces brain swelling, intracranial pressure, slows down brain cell metabolism, reduces the toxins that the brain cells release after a hypoxic event, and increases the repair of brain cells, all of which reduces the extent of the damage to the newborn baby’s brain. Whilst this may sound a little incredible, if administered correctly, cooling has been found to reduce significantly the physical disability or cerebral palsy that would normally be caused by a moderate or severe HIE brain injury. In many cases, cooling is so effective that children who were born with HIE go on to meet their early developmental milestones and are left with little or no obvious physical disability.

Neonatal intensive care and cooling is currently the best available treatment for babies after hypoxic brain injury.

Why does my baby need cooling?

If your newborn baby is offered treatment with cooling, this is because their doctors believe they have suffered a hypoxic (HIE) birth injury. Treatment with cooling has been found to reduce the permanent physical disability that is often experienced by babies after a moderate or severe HIE birth injury.

National guidance by the National Institute for Health and Care Excellence (NICE) recommends cooling for all eligible newborn babies with moderate or severe HIE who are expected to survive, as long as the treatment is carried out in accordance with recognised safety criteria. This means that cooling is standard treatment for most babies who are born with moderate to severe HIE birth injury. Cooling is not offered to babies born before 36 weeks of pregnancy.

As cooling must take place as soon as possible after the baby’s birth injury to be effective, the process of sharing information and obtaining consent can sometimes feel rushed and confusing for parents. NICE guidelines require neonatal teams to ensure that, as the baby’s parents, you understand what is involved and agree to the cooling treatment.

What are the benefits of cooling?

When a baby’s brain is deprived of oxygen (hypoxia) before, during or immediately after their birth, this causes brain injury and cerebral palsy disability. Hypoxic birth injury cannot be cured. However, research and over a decade of cooling treatment have shown that if given correctly, cooling significantly reduces the severe physical disability that would otherwise follow an HIE birth injury. In fact, therapeutic hypothermia or cooling has been so successful in slowing the progression of HIE brain injury that, even where MRI scans confirm an HIE injury to a newborn baby’s brain, the growing child retains their motor (muscle movement) coordination, mobility (ability to walk) and communication, which are usually the major challenges for children with cerebral palsy from HIE birth injury.

Cooling is so effective in reducing long-term physical disability following hypoxic birth injury that NICE guidance now recommends cooling for all eligible newborn babies with moderate or severe HIE.

Our own experience as specialist solicitors in cerebral palsy claims confirms that, despite their severe brain injury, children born with moderate or severe HIE who have been cooled now tend to be far less physically disabled than those we were helping before cooling became standard treatment in 2010. We have also seen from our own experience that despite a post-cooling ‘all clear’ diagnosis, it can take time to know for sure whether your child will need additional support with common (but much less obvious) neurological effects of their injury, which may only come to light when they struggle to keep up at school, or during their transition into work or independent life.

What happens when a baby is cooled after birth injury?

If treatment with cooling is recommended for your baby, it should be carried out under strict safety conditions. Cooling treatment must take place in a specialist neonatal intensive care unit and must be carried out and monitored by staff with training and experience in using therapeutic hypothermia to treat severely ill newborn babies.

Your baby’s neonatal care team must explain to you the benefits and risks of the treatment, and ensure that you understand what is involved and agree to your baby being cooled. To be safe and effective, cooling must start as soon as possible, and in any event no later than six hours after your baby’s birth. This means that decision-making and arrangements must happen very quickly to give your baby the best chance of a successful outcome. As NICE guidelines require all cooling treatments to take place in a specialist neonatal unit, your baby may need to be transferred to another hospital or a regional neonatal intensive care unit (NICU) if your birth hospital does not have the necessary specialist facilities to provide the cooling.

During cooling, your baby’s body temperature will be safely lowered from their normal temperature of 37°C and kept at a temperature between 33C° and 35°C for 72 hours. This is usually done by placing the baby on a fluid-cooled mattress or in a fluid-cooled wrap, or by cooling their head with a special cap. Their temperature is monitored closely throughout the cooling treatment with a rectal thermometer. At the end of the cooling period, their temperature will be brought back up to normal temperature (rewarmed) very gradually over several hours.

Your baby should continue to receive full neonatal intensive care whilst they are being cooled, and their condition must be monitored carefully before, during and after their cooling treatment. Their neonatal team will be checking their body and brain’s response to the treatment, with checks such as blood gas and glucose levels, brain activity, checking for signs of infection, administering sedation and pain relief, and providing them with respiratory and cardiovascular support.

You should be able to hold, touch and talk to your baby during their cooling treatment, but this may be limited if your baby is very unwell or if they are attached to a lot of equipment.

Can babies with mild HIE have treatment with cooling?

If your baby is born with mild hypoxic ischaemic encephalopathy (HIE) it is unlikely that they will be offered treatment with cooling. NICE guidelines only recommend treatment with therapeutic hypothermia for babies born with moderate or severe HIE, owing to the treatment’s proven benefits in reducing physical disability. Babies born with mild HIE may experience some subtle difficulties over time, but they do not usually have the severe physical disability that cooling is known to reduce.

Whilst some hospitals are currently offering cooling treatment for babies with mild HIE, this does not reflect recommended practice. Research is underway to explore whether babies with mild HIE should be exposed to the risks and additional invasive treatment and monitoring involved in cooling, without the proven benefit of a significant reduction in physical disability. The outcome of the research is expected to lead to changes in the guidelines which will either extend or more firmly restrict when cooling can be used.

What are the risks of cooling?

Cooling is a relatively new, specialist procedure and, like all medical treatments, cooling has its risks and complications. Your baby’s neonatal team should discuss with you the benefits and risks of cooling, so that you understand what the treatment involves and how it might affect your baby before agreeing to the treatment.

Cooling has been accepted as a safe treatment for moderate to severe HIE birth injury, when administered correctly in specialist neonatal units, since 2010. Cooling is currently recognised as the best available treatment to reduce severe life-long disability in babies who have suffered moderate or severe HIE birth injury. It has potentially life-changing benefits for seriously injured babies who would otherwise develop cerebral palsy disability. Given its proven benefits and NICE recommendation as a standard treatment for newborn babies with HIE birth injury, failure to offer cooling to an otherwise eligible baby with moderate or severe HIE could be regarded as negligent.

Clinical studies have found that therapeutic hypothermia or cooling is generally safe as long as it is correctly administered and carefully monitored by fully trained staff in a specialist neonatal intensive care unit. Babies undergoing cooling must also receive neonatal intensive care, which involves regular blood tests, monitoring of their blood pressure, heart rate and brain activity and checking for signs of infection.

At the end of the cooling period, your baby’s body temperature will gradually be brought back up to normal. The process of ‘rewarming’ must take place gradually and must also be monitored carefully. Mistakes during the rewarming process can cause reperfusion injury, further damaging the baby’s brain by returning the blood to it too quickly.

Mistakes in cooling can cause further injury to a severely injured baby’s brain, leading to additional lifelong disability. Medical negligence claims involving injury from cooling treatment errors usually arise from failure to follow the strict safety protocol. Common mistakes include failing to start the cooling treatment within six hours of the baby’s birth, failing to provide full neonatal intensive care and monitoring of the baby, and failure to control the baby’s temperature leading to over-cooling or rapid rewarming.

In a recent case, our client’s birth injury was compounded by cooling mistakes during transfer to a more specialised neonatal unit, resulting in a lengthy period of cooling at a dangerously low temperature. Similarly, the Ockenden review into maternity failures at Shrewsbury and Telford Hospitals NHS Trust raised concerns about the therapeutic cooling of many of the babies who suffered HIE brain injury as a result of their negligent maternity care.

Does cooling cause autism, ASD or ADHD?

Since cooling has been used routinely to prevent babies with moderate or severe HIE birth injury from developing cerebral palsy disability, we have found that more families are coming to us for help with children and teenagers who were cooled and later developed problems with attention and behaviour, diagnosed as autism or attention deficit hyperactivity disorder (ADHD). These children are less physically disabled than would otherwise be expected from their birth injury, but their behavioural and neurodevelopmental disability will still have a life-long impact on their family and the child, limiting their ability to learn, work, socialise and be safe around others, or live independently in adult life.

We cannot say whether cooling ‘causes’ autism or ADHD, as the scientific understanding of these conditions is still developing. However, our medical experts tell us that unless there is strong evidence of another cause, the ASD/ADHD traits which develop in later childhood and teenage years can be attributed to the cooled child’s HIE birth injury.

Read more about the link between HIE birth injury, cooling and autism/ADHD.

Does MNSI investigate HIE birth injuries involving cooling?

The Maternity and Newborn Safety Investigations (MNSI) programme investigates birth injuries to newborn babies who have had a diagnosis of severe brain injury, including babies with grade III (severe) hypoxic ischaemic encephalopathy (HIE) or treatment with cooling.

MNSI no longer routinely investigates HIE birth injuries where the baby’s MRI scan or neurological examinations show no obvious evidence of ongoing brain injury, such as after the baby has been cooled. The exceptions to this are where the baby’s family or the NHS trust responsible for the mother’s maternity care request an investigation, or where a baby with mild HIE has been cooled as part of the COMET trial into cooling for mild HIE.

If you have been contacted by MNSI after the birth of your baby, or you are unsure whether an MNSI investigation is right for you, our experienced birth injury solicitors are here to help. You can talk to a solicitor, free and confidentially, by contacting us.