Convulsions

Sometimes, due to various reasons, a sudden excessive electrical discharge in neurons, or brain cells, results in brief brain dysfunction which can manifest as convulsions, sensory disturbances and/or loss of consciousness. This phenomenon is known as a seizure and if two or more of these occur, the patient is said to have epilepsy.

Convulsions can be experienced as jerky twitching movements throughout the body or only in a few areas, depending on the type of the seizure or the part of the brain involved.

This convulsive activity may also spread to other regions of the body as the seizure progresses. Seizures can be preceded by certain warning signs, or aura, and are usually followed by a state of lethargy, confusion and inactivity known as the postictal phase. 

As convulsions don't occur without seizures, here's a quick look at seizures:

Broadly, seizures can be divided based on part of the brain affected: generalized (entire brain) or focal/partial (limited to a certain area or half of the brain).

Generalized seizures can be of the following types:

• Absence seizure: Also known as a petit mal seizure, an absence seizure is characterized by patients, usually children, staring blankly ahead for 15 to 20 seconds. Repeat attacks are common and up to 100 may occur in a day. These may go unnoticed unless they are associated with unconsciousness. Atypical absence seizures can be associated with jerking of arms.
• Generalised tonic-clonic seizure: Also known as grand mal seizure, a generalised tonic-clonic seizure begins with the patient becoming unconscious, after which their breathing stops and the body becomes rigid, later jerky movements or convulsions develop, and finally the patient passes into a state of inactivity and slumber.
• Tonic seizure: Causes patients to experience unexplained tension of rigidity in their limbs or trunk, which lasts less than a minute. If standing, the patient may fall.
• Clonic seizure: Rhythmic jerking movements (convulsions) occur throughout the body or in parts of it. These movements cannot be stopped by restraining the patient or repositioning the afflicted body part.
• Atonic seizure: The patient’s body loses its tone and goes limp. Also known as drop attacks, the loss of muscle power causes patients to buckle and fall. The patient's eyelids may droop and their head may bob forward. 
• Myoclonic seizure: The patient experiences jerky jolts, similar to when one is jolted upright while drifting asleep, repeatedly. Consciousness is not lost throughout.

Focal or partial seizures are limited to a certain region of the body. These may manifest as movement abnormalities, sensory changes (like visual disturbances or ringing in ears), loss of bowel or bladder control, and/or impaired cognition. 

Additionally, if the patient’s awareness of his/her surroundings is impaired, it is considered to be a complex seizure.

The signs of convulsions may include:

• Lack of awareness of surroundings
• Eyes rolling back
• Changed breathing
• Rigidity or stiffness in the limbs or in the entire body
• Jerky, uncontrollable movements of some parts or of the entire body
• The patient is unabie to respond

Convulsions may accompany a seizure, though a seizure may occur without convulsions. It is important to state the signs of a seizure in any literature on convulsions, as seizure signs could also portend convulsions in some cases:

Some people can perceive changes in their mood or behaviour hours prior to an oncoming seizure spell. The events of the actual seizure spell can be described in three stages:

• Aura: Warning signs, or aura, is usually felt immediately before the seizure. The following signs could possibly be present:

  • Headache
  • Nausea
  • Dizziness 
  • Panic or anxiety
  • Altered taste, smell or sounds
  • Vision difficulties 
  • Numbness or tingling 
  • Déjà vu (the feeling that you’ve experienced something before that you haven’t actually)

• Seizure: In this phase, there’s increased electrical discharge in brain cells. Features of the aura may be carried forward but additional features can include:

  • Loss of consciousness 
  • Loss of awareness of surroundings 
  • A cry may be given out by the patient 
  • Stiffening of the body or part of it
  • Breathing may stop
  • Patient may turn blue
  • Dilated pupils
  • Loss of bowel or bladder control
  • Uncontrollable twitching movements 
  • Frothing at the mouth
  • Rolling of eyes 
  • Repetitive movements (like lip-smacking)
  • Racing heart (tachycardia)

• Postictal phase: After the seizure activity stops and the patient begins to recover, the following can be expected:

  • Sleepiness
  • Headache 
  • Weakness
  • Memory lapses 
  • Confusion

Convulsions are often linked to epilepsy. In most cases of epilepsy, the cause is unknown. In such cases, there usually exists a history of epilepsy in the family. Inherited cases usually begin experiencing seizures in childhood and in a few cases, might even grow out of them with age. 

In some children under the age of five, fever (of any cause) is accompanied by convulsions. It is important to anticipate seizures in such children each time they fall ill.

However, seizures may not always be due to epilepsy or associated with fever but secondary to some other disease or metabolic derangement. These causes should be considered in cases where the onset of seizures is later in life.

Causes of acquired seizures—and, potentially, convulsions—include: 

• Metabolite abnormalities: Hypoglycemia (low blood sugar) that can occur during long periods of fasting or in diabetes patients on the wrong dosage of oral diabetic drugs or insulin may cause seizures, sometimes with convulsions.
• Alcohol or drug withdrawal: Patients suffering from alcohol or drug addiction may experience convulsions when unable to consume these substances.
• Head trauma: A traumatic injury to the brain can also result in seizures.
• Brain infection: Infection of the brain (leading to brain swelling or encephalitis) or surrounding protective layers (meningitis) have seizure potential.
• Stroke: Cardiovascular accidents deprive the brain of oxygen thereby damaging brain tissue and altering brain function. These, too, can cause seizures. 
• Neurodegenerative diseases: Brain diseases in which cells are lost, like Alzheimer’s disease or other types of dementia, result in abnormal brain function, and possibly, seizures.
• Brain tumour: A growing brain tumour may cause brain dysfunction and seizures may follow.
• Eclampsia: Eclampsia is a serious complication of pregnancy in which the patient typically has high blood pressure (gestational hypertension), protein in their urine or proteinuria (often but not always) and seizures, sometimes with convulsions.

Convulsions are marked by stiffness and then uncontrollable jerky movements of the body. The person having convulsions is usually unable to respond and may be unaware of his/her surroundings. All this may seem scary but it is important to remember that the movements of convulsion are not in the patient's control and the patient could really hurt themselves unless you help them. Here are some things you can do while you wait for medical help to arrive:

• Lay the person down on the floor to avoid falls
• Clear the surrounding area to avoid injury
• Turn the person to one side to aid breathing
• Remove eyeglasses, if the person wears spectacles or sunglasses
• Loosen any tight straps of clothing like ties and scarves
• If possible, place something soft to cushion their head
• Time the seizure, if it persists for more than 5 minutes, immediately visit the hospital 

Immediately visit the hospital if:

• The patient is having a seizure for the first time
• The seizure lasts for more than five minutes
• Two or more seizures occur
• The patient is pregnant
• The patient is diabetic
• The patient is injured

The most common cause of seizures with convulsions is epilepsy. Here’s how epilepsy is diagnosed:

Epilepsy is first diagnosed clinically and then confirmed with investigations. After the convulsive episode has been labelled as a seizure, it is classified and the underlying cause is determined.

• Clinical diagnosis: Based on the medical history taken from the patient, family members and witnesses, the seizure spell is classified. Two or more seizures occurring within 24 hours is diagnosed as epilepsy.
• Investigations: Your doctor may advise certain tests, such as:
  • Electroencephalogram (EEG): Electroencephalogram (EEG) is the most appropriate first-line non-invasive test performed by placing electrodes on the scalp. By assessing and translating electrical conduction activity in the brain as various wave patterns, it aids diagnosis.
  • Computed tomography (CT): A CT scan generates 3D images using an X-ray machine. It helps in identifying any anatomical anomalies in the brain or presence of any tumours which may cause focal or partial seizures.
  • Magnetic resonance imaging (MRI): Replacing X-rays with magnetic resonance, an MRI scan performs the same function as the CT scan but shows a more detailed picture to the doctor.
  • Positron emission tomography (PET): PET scan is based on the principle that cancer cells utilise more sugar (glucose) than normal cells. Hence, radioactive-labelled glucose is injected into the patient and its uptake by atypical cells is measured. A scanner detects this and helps in generating images of the organ involved, and helps to view the active areas of the brain.
  • Single photon emission computed tomography (SPECT): Using radioactive substances, the originating site of seizure activity is identified.
• Biochemical investigations:
  • Complete blood count (CBC): The CBC test measures various kinds of blood cell counts. An elevated white blood cell count can help point the doctor to a possible brain infection. 
  • Blood glucose levels: A deranged blood glucose level can cause seizures and is the first parameter that needs to be ruled out.
  • Cerebrospinal fluid analysis: A lumbar puncture (spinal tap) is done to obtain a small amount of the fluid surrounding the brain and the spine. After numbing the small of the back, a needle is inserted and some fluid is withdrawn. Tests performed on this fluid can uncover a brain infection. Some patients experience a headache after a spinal tap.
  • Blood culture: Helps catch any blood infection. 
  • Toxicology screening: Detects blood levels of addictive substances: alcohol and various drugs can cause seizures.

The treatment of convulsions depends on the underlying cause. As epilepsy is the most common cause of seizures with convulsions, here’s a quick look at the treatment options for epilepsy:

• Drug therapy: Anti-epileptic drugs (AEDs) are prescribed by the doctor after thoroughly examining the patient
• Brain surgery
• Vagus nerve stimulation
• Ketogenic diet

The aim of treatment in epilepsy is to reduce the number of seizure episodes and ultimately stop the convulsions completely.

By modifying the chemical substances in the brain, anti-epileptic drugs (AEDs) can stop seizures from happening in 70% of patients. However, these drugs cannot cure the disease. Therefore, patients need to take medicines regularly.

Medications that are used for this include:

• Lamotrigine
• Carbamazepine
• Sodium valproate
• Levetiracetam
• Topiramate

Depending on the type of seizure, age, sex and other comorbidities, the doctor chooses the best AED for each patient.

How to take AEDs:

These medicines can be taken as tablets, capsules or in liquid form every day. Usually, a single anti-seizure medicine is initiated at the lowest dose. The dose is increased gradually till optimal seizure control is attained. If at the maximum dose seizures are not controlled, another drug may be added or the first one will be replaced.

Once on AEDs, a missed dose increases the likelihood of having a seizure. If a patient goes seizure-free for two years, the medication will gradually be stopped over the next few months.

All other medicines being taken for other conditions should be disclosed to the doctor to prevent possible drug interactions.

Common side effects of AEDs include:

• Sleepiness
• Agitation
• Headaches
• Nausea and vomiting
• Uncontrollable shaking (tremors)
• Hair loss
• Excessive hair growth
• Gum swelling
• Rashes
• Reduced energy levels

Follow-up:

After the patient starts taking anti-seizure medicines, blood concentrations are regularly monitored to ensure that the adequate dose is being given to effectively control seizure activity. These are usually performed when the patient is taking the following:

• Carbamazepine
• Phenytoin
• Valproic acid
• Phenobarbital

Treatment can help most people with epilepsy have fewer seizures, or stop having seizures completely.

If seizures are uncontrolled despite giving the patient combined AEDs, and radiological imaging confirms the presence of a physical abnormality like a tumour in the brain, brain surgery can be considered. Surgical removal of the problematic area could make the patient seizure-free.

Pre- surgical testing:

• Brain scans such as CT, MRI, PETor SPECT
• Electroencephalogram (EEG)
• Memory and learning ability testing

Surgery:

While the patient is sedated, a small incision is made on the scalp and the troublesome part of the brain is removed.

Complications of surgery:

• Effects of general anaesthesia: drowsiness, sedation
• Memory problems
• Mood changes
• Behavioural changes
• Visual problems
• Recurrence of seizures

A small electronic device is placed underneath the skin in contact with the vague nerve. It stimulates the vagus nerve and in turn alters electrical activity in the brain, making seizures less frequent.

Potential side effects:

• Hoarse voice
• Cough
• Sore throat

A high fat, low carbohydrate and protein diet is useful in reducing seizures in children — especially those children who are not responding to AEDs — by altering chemicals in the brain.

(Read more: Ketogenic Diet)

While no AED is completely safe in pregnancy, valproate is generally avoided in women of reproductive age. In case an epileptic patient, who has been seizure-free for two years or longer, plans a pregnancy, no anti-seizure medication is required. However, if she has experienced a seizure in the last two years, she will slowly be weaned off her present AED and started on one of the three drugs preferred in pregnancy:

• Levetiracetam
• Lamotrigine or
• Carbamazepine

In case of an accidental pregnancy while on AEDs, the medication should not be discontinued or replaced. Doing so could increase the risk of seizures and pregnancy loss. Drug levels should be monitored throughout pregnancy to strictly control seizures.

Most patients lead normal lives with regular anti-seizure medication. If patients remain seizure-free for two years or longer, they may be advised to stop medication altogether. Overall, the outcome depends on the cause of the seizures; they tend to be worse for acquired incurable conditions like brain tumours. If the onset of seizures is at a younger age, patients may even outgrow them. A very slim, less than 1%, chance exists of sudden unexplained death in epilepsy.