Birth injury series - jaundice and kernicterus

Following their birth babies can become jaundiced. This can usually be easily identified by the yellowing colour of their skin and is usually recognised quickly by midwives. The discolouration occurs because new babies produce too much of a substance called bilirubin (a normal by-product produced by the breakdown of red blood cells) and their small bodies cannot always cope with and dispense the excess. If bilirubin levels become too high then they can become toxic or poisonous to the baby. In extreme circumstances an excess of bilirubin can lead to a type of brain damage known as Kernicterus.

Jaundice is very common in new-born babies and fortunately the treatment is very simple and straightforward using phototherapy or light treatment. It is non-invasive and is generally highly effective in helping the baby’s body to break down and dispose of the excess bilirubin in the blood.   Occasionally, but more rarely, the bilirubin levels need to be brought down to safe levels by an “exchange transfusion” (a blood transfusion) but the majority of cases of jaundice will require only phototherapy and will be resolved quickly.

Jaundice is therefore rarely a medical emergency but it is important that staff identify when a baby is jaundiced and commence phototherapy treatment when required. The bilirubin levels should be measured on a regular basis to ensure they remain at a safe level. Where bilirubin levels are identified as being high then the levels should continue to be monitored carefully to ensure they are brought down to a safe level as quickly as possible. They should not be permitted to rise to potentially toxic levels or to stay at a dangerous level for long as the longer the levels remain high then the greater the risk of permanent and irreversible harm.

Babies born at full term and who are healthy are at a much lower risk of suffering from injury as a result of too much bilirubin. The risks are usually limited to the first few days of life and will often resolve spontaneously even without phototherapy. The level at which bilirubin becomes toxic will depend on the age and the size of the baby.

Low birth weight and extremely premature babies will therefore be at much greater risk of suffering injuries. These can also be very sick babies and so they will be more vulnerable. Phototherapy should therefore be started sooner (and at a lower threshold level) than would be necessary with a full term and well-baby. Hospitals and midwives should therefore be alert to the development of jaundice and the importance of early and on-going treatment with phototherapy if this is needed.

Unfortunately kernicterus brain injury can occur where the jaundice has not been identified and the correct level of treatment has not been provided. The classic signs of kernicterus brain damage may include some but not necessarily all of the following clinical features:

1. Hearing problems: The cochlear and the auditory nerve are particularly vulnerable to too much bilirubin and can be damaged.
2. Hypotonia: Floppy or limp limbs and delay in reaching physical milestones may be an early sign from around 6 months of age.
3. Athetosis and/or chorea: A baby/child may have unbalanced involuntary movements. Their muscle tone may not seem right and they may display writhing movements. A diagnosis of cerebral palsy may be made.
4. Visual problems: These may appear as upward gaze palsy or inability to move the eyes to look up. The ability to look down is not usually affected.
5. Enamel dysplasia: This is a defect of the teeth in which the enamel is hard but thin and deficient in amount. The teeth may have green staining. Enamel dysplasia will occur in the majority of cases.

Some of the features identified above can arise because of other conditions or illnesses, but the combination of these features may mean that kernicterus brain damage has occurred.

This article first appeared in At Home Magazine. 

Further information

For more information, please visit our page on Cerebral Palsy and Birth Injury. You may also be interested in reading some of our other blogs on this topic, including; 

• Birth injuries series - Fetal distress
• Birth injuries series - Erb’s palsy or brachial plexus injuries
• Home birth v hospital birth – which is safer? The debate continues and 
• Identifying problems before a baby is born: Antenatal diagnosis of fetal anomaly

Kingsley Napley is experienced in acting in clinical negligence claims relating birth injuries. If you would like advice, please contact the Clinical Negligence and Personal Injury team on 020 7814 1200 or by emailing us at clinnegenquiries@kingsleynapley.co.uk.