A seizure occurs when the normal functioning of the brain is disrupted by disorderly or excessive firing neurons. This leads to abrupt changes in neurological function, such as:
- Changes in level of alertness (staring, unconsciousness)
- Abnormal sensations (such as smelling something that isn’t there)
- Abnormal movements (eye fluttering or repetitious jerking of part or all of the body)
Seizures or convulsions are not uncommon after TBI, but repeated post traumatic seizures (PTS) are uncommon. Early post traumatic seizures occur within the first seven days after the brain injury. These seizures are relatively common and do not correlate with the severity of the injury. They also don’t predict whether epilepsy – seizures that occur on an ongoing basis – will develop. Late seizures, occurring after the first week, are more predictive of the chance of developing post traumatic epilepsy. Also, the more severe the brain injury, the more likely epilepsy will develop.
Overall, the risk of developing post traumatic epilepsy after a closed head injury is 5-7%. If there is a closed head injury with associated mild TBI, the risk of developing epilepsy is no greater than any other person. If there is severe TBI, the risk of developing epilepsy climbs to around 11%. In contrast, with penetrating TBI, the risk has been reported to be around as high as 35-50%. The accident victim is at most risk of developing on going post traumatic seizures during the first two years after TBI.
Several risk factors have been reported to increase the chances of developing ongoing PTS. These include, but are not limited to:
- Focal injuries (such as epidural hematoma, cortical contusion, intrecerebral hematoma)
- Wounds with penetration of the dura
- Early PTS, and
- Factors reflecting increased severity of the brain injury (coma, prolonged amnesia)
If the accident victim has a recurrent rate of seizures, then your doctor will need to treat them as soon as possible. The medication chose will depend of the age of the accident victim, the severity of the brain injury, and their ability to handle medication. Some medications are covered by drug plans and OHIP. Others aren’t. This can get very costly to the family because some brain injury medications are very expensive.
Some doctors might recommend discontinuing certain types of medication as they may have induced, or increased the risks of seizures. It’s important that you speak with your doctor about this before you decide to unilaterally discontinue the use of any medication.
Seizures can be classified into several broad categories. If the seizure remains focal or localized to a part of the brain, that seizure is referred to as a focal or partial seizure. If the seizure affects the function of the entire brain, it’s called a partial seizure. If it starts as a focal seizure, but then spreads to the entire brain, it’s called a partial complex seizure. The most common type of seizure associated with traumatic brain injury is a partial seizure.
What you observe during a seizure and your response will depend of the type of seizure. The seizure may be something as subtle as a starting spell lasting only seconds, with or without some repetitive movement, or it may involve repetitive jerking of part or all of the body, loss of consciousness, and incontinence. Some seizures are preceded by unusual sensations, called an aura. This may alert the injured party and their family that a seizure is about to come on. Sometimes rage behavior is a precursor to a seizure. The pre-seizure signs vary, and are different for each and every accident victim.
Do NOT panic if the injured party has a seizure. Talk to your doctor and members of the rehab team to develop an action plan in the event of seizure. You should know what to do to protect the safety of the brain injured accident victim, along with the safety of those around them. It should be pointed out that all seizures are self-limiting. They generally last between 1-2 minutes. Do NOT put anything in the mouth of the accident victim while they are experiencing a seizure. This might break their tooth, or cause permanent injury to their mouth or jaw. When the seizure stops, it’s common for the accident victim to be dazed, drowsy or feeling ill. Your doctor or neurologist will be able to give you more insight on what to do, and what to expect following a seizure.