The ANSeR project is attempting to test a computer system (algorithm) that can detect seizures in babies.
Here are a few frequently asked questions you may have.
The brain is made up of millions of nerve cells that are all connected together. Each of these nerve cells (neurons) create and receive tiny electrical signals which control many aspects of our body functions. All neurons work together in a very complex but highly organised and coordinated way. As babies grow up and develop new skills, the organisation of their neurons develops too so it can all work.
A seizure – sometimes called a ‘fit’ or a ‘convulsion’ – can happen when the brain becomes disturbed in some way (what causes seizures?). The communication between individual neurons is altered and many neurons send out impulses at the same time. This simultaneous ‘discharge’ produces the symptoms we recognise as a seizure.
A seizure may occur together with movement patterns typically understood to accompany seizures or it may have no obvious signs. This is particularly the case with babies.
Recognising that a baby is having a seizure may be quite difficult even for experienced doctors. Seizures in babies are very different compared to seizures that occur as part of Epilepsy in older children and adults.
The most common sign that a seizure is happening is a run of repeated “jerky” or “twitching” movements of the arms or legs that continue when we gently hold one of the limbs to see if the movements stop.
Other babies have changes in their behaviour – such as repeated hiccoughs, jerky movements of the eye or lip-smacking/chewing movements – although we see these behaviours in babies that are not having seizures.
Because seizures can be very difficult to identify and diagnose, it is really important to check whether the movements occur with changes in the function of the neurons in the brain – we do this by making a recording of the brain waves – called an electroencephalogram or EEG. The ANSeR software system will help doctors and nurses detect these seizures and ultimately treat them earlier.
Once you are discharged from hospital you might find yourself in a situation where you are not sure if some of your baby’s movements are due to seizures or not. Newborn babies can show a variety of movements that might be misinterpreted as seizures.
Many babies can show some degree of jitteriness when they are crying or when they are asleep. This jitteriness diminishes during the first weeks after birth and is less frequent in quietly wakeful infants. It should get less noticeable once you pick your baby up.
Other babies have repeated single jerks of the limbs during sleep (usually when they are dropping off or waking up). We call this “benign neonatal sleep myoclonus” and it stops when the baby wakes up. Neither of these need any treatment. The ANSeR software system will ultimately help doctors and nurses make decisions on which babies are actually having seizures and need treatment.
Your doctor will look for repetitive movements that are not triggered by touch or noise, particularly if your baby looks “distant” when they are happening. These movements tend to occur in a cluster or group, which means you will see more than one seizure in a row. Each seizure will most probably look very much like the others. Some seizures only involve a part of the brain (focal seizures) and you might see one arm or one leg twitching or getting stiffer for a short period. Other seizures might involve the whole brain (generalized seizures) where the baby might show changes in breathing rate and their skin colour may turn slightly pale or bluish.
If you observe repeatedly abnormal movements and are not sure about their significance, try to video them (a smart phone is usually sufficient) so your doctor can have a look at them.
Most seizures end after a very short time (some seconds to a minute). Very few babies develop longer lasting seizures where urgent treatment is needed (more info below). When your baby is discharged from the hospital, your doctors will tell you what to do in case of a seizure. In general, short seizures that last only a few seconds do not need any immediate interventions, but longer seizures may require medication and you may need to call an ambulance. When a seizure occurs and you are not familiar with the situation, it is reasonable to seek the advice of a doctor.
Epilepsy refers to more than one seizure, usually a run of seizures, occurring usually in an older child or adult. We do not refer to seizures occurring in newborn babies (neonatal seizures) as Epilepsy. Less than 1-in-5 babies who have neonatal seizures will go on to have seizures of some type later in life, and even fewer go on to develop Epilepsy.
Epilepsy is a group of conditions, taken together these are termed the Epilepsies, which differ widely in the age of onset, types of seizures, response to treatment, and underlying and concomitant disorders.
Most neonatal seizures either settle spontaneously or respond well to treatment. To a large extent this depends on the reason the seizures are happening.
In most babies with seizures, we can find an underlying disorder or cause. We know that the young developing brain is more susceptible to seizures and the underlying mechanisms for this are still a field of intense medical research. We know that frequent seizures usually stop as a baby gets older and this may be to do with brain substance and structural changes as the baby develops. For instance, neurotransmitters, the chemicals that interact with nerve cells to pass on electrical signals through the synapses, change with age: an important neurotransmitter called gamma-aminobutyric acid (GABA) increases transmission in babies whereas in older children or adults it decreases transmission.
The range of conditions that causes neonatal seizures can also vary with gestational age. Extremely preterm infants often have bleeding into the immature brain whereas in term infants it is usually a lack of oxygen around the time of birth or a “stroke” that causes the seizures. Sometimes an infection or changes in blood sugar or blood salt levels may give rise to seizures and this can be treated. In other cases babies are born with an abnormality of brain development, a disorder of the body’s chemistry or metabolism, and some babies carry a genetic change that makes them more likely to have seizures. Your doctor will explain if he or she thinks that one of these conditions is causing the seizures.
Seizures are more common in the newborn period than during any other time throughout life. Between one and three in 1000 develop seizures (0.1%-0.3%), so they are relatively rare events – jitteriness and myoclonus are much more common. Seizures may occur more frequently in babies born prematurely, when the brain is still more sensitive to disturbances. Most seizures happen during the first days after birth and are much less frequent after the first week.
A small number of babies show signs of stress at delivery and need help to breathe. This could be a sign that the baby suffered lack of oxygen or blood supply before/during birth. Most do well once they have settled after birth, but some need extra care and support. The worry is that the brain has suffered from this period of poor oxygen or blood supply. If this period is prolonged and injures the brain, we call this asphyxia. This can cause swelling of the baby’s brain leading to irritability or excessive sleepiness during the first few days. The medical term we use for this is ‘encephalopathy’. We can assess the degree of encephalopathy through a change of electrical brain activity by doing an EEG (see section below). Most babies with encephalopathy get better without treatment, although for those with more severe brain injuries we can treat them by reducing the baby’s body temperature to around 33.5˚C for 72 hours (we refer to this as “cooling” or use the technical term “therapeutic hypothermia”). Your doctors will answer any questions you have about this.
Sometimes seizures are the first sign of what is called a “stroke”. This happens when one of the brain’s blood vessels becomes blocked, usually with a clot. This leads to an area of the brain becoming injured in a similar fashion to what happens to the whole brain in asphyxia, as above. We think these strokes happen in the newborn period because of changes in the system that allows blood to clot. Many strokes only affect small areas of the brain but some are more extensive. Often we do not notice anything other than seizures in the period after birth. As the tissue responds to the injury, it may trigger seizures. Sometimes these are confined to one area but they also may spread. There are many types of stroke and your doctor will explain what has happened to your baby.