Seizures vs. Convulsions

People often confuse "seizures" with "convulsions" (along with the inclusion of "tremors," "fits," "conniptions," and "the shakes"), and whereas in the field using "seizure" and "convulsion" interchangeably won't affect your management, still, they are technically different.

DEFINITIONS:

• Seizures are mental storms. They signify abnormal changes in the activity of the brain. (Seizures happen in the head--not on the floor!) Depending on where in the brain the abnormal series of synapses are firing can determine the clinical expression that is witnessed.
• Tremors are involuntary rhythmic movements of muscles of the limbs, usually due to abnormalities in a particular motor part of the brain for the limb(s).
• Convulsions are the generalized, erratic involuntary muscular movements that encompass the entire body, consisting of violent shaking and rhythmic, repeating contractions. (Convulsions happen on the floor!)

Seizures are not convulsions but can result in convulsions when the abnormal brain activity encompasses the extent of the motor area. These are called "grand mal seizures" (an obsolete term) or major motor or major tonic-clonic seizures.

• Tonic vs Clonic: The tonic phase of a seizure is associated with skeletal muscle tension and decorticate posturing and normally lasts only a few seconds. In this tonic phase, the body becomes entirely rigid, and in the clonic phase, there is uncontrolled jerking. 

 

SEIZURES

Any insult to the cerebral cortex can cause seizures. Disturbed metabolism (fever, hyponatremia, etc.), trauma (concussion), ischemia (embolus, hypoxia), inflammation (infection), or bleeding (trauma, stroke, coagulation disorder) can cause them.

Seizures have distinct stages:

1. Prodrome--mostly emotional signals.
2. Aura--alterations in activity, emotions, hearing, smell, taste, or visual perceptions.
3. The seizure (the ictus.)
4. Postictal state--recovery stage in which the person is unresponsive, progressing to drowsy and confused. Immediate recovery may confuse the emergency responder into thinking it wasn't an epileptic seizure.

Seizures can be either

• focal or
• generalized:

 

Focal Seizures

• focal motor seizures provoke focal motor activity, sometimes with a "marching" anatomic spread;
• sensory seizures with paresthesias (distortion of touch sensation) and distortions represented as vertigo and in taste, smell, hearing, and vision (such as flashing lights);
• autonomic seizures with a stomach-rising feeling, sweating, piloerection, and pupil changes.
• auras: focal seizures with impairment of awareness: deja vu, time distortions, fear, illusions, and hallucinations;
• "silent" seizures that originate in "silent" areas of the brain such as the frontal lobes.

In the focal seizures with impairment of awareness, there may be repetitive semipurposeful movements that are referred to as motor automatisms. These can include oral-buccal movements (chewing, swallowing, sucking), complex motor phenomena including bicycling and kicking movements, flailing of the arms, and even running, jumping, and spinning.

When they involve the temporal areas, they can result in "absence seizures," in which the child "zones out." These are referred to as "petit mal seizures" (another obsolete term) and temporal lobe seizures. In limited bursts, they can cause unconscious tremors, clenching, and posturing.

 

Generalized Seizures

Generalized seizures, by definition, must involve both hemispheres (bilateral). They are also called major motor seizures, major tonic-clonic seizures, and grand mal (obsolete) seizures.

Epileptic Seizures:

Not all seizures are epilepsy.

Having seizures does not mean epilepsy unless there are diagnostic criteria that are met, which are consistent with lasting derangement of normal brain function.

A pseudoseizure also called a "nonepileptic convulsion" or a "psychogenic nonepileptic seizure (PNES), is triggered by any mechanism other than cerebral discharge. They are heavily associated with mental illness and tend to be recurrent and are not associated with abnormal electrical neuronal activity.

One of the characteristics of epileptic seizures (the ictal state) is what is called the Postictal state.

The postictal state is the abnormal condition occurring between the end of an epileptic seizure and a return to baseline condition, usually lasting several minutes when a person is unresponsive. Applying this definition accurately, however, can be difficult, especially in complex partial seizures where cognitive and sensorimotor impairments merge imperceptibly into the postictal state.

In status epilepticus, the postictal state can last for longer periods of time than the usual 20-30 minutes. The two most common reasons for delayed postictal recovery are sedation from medications and ongoing non-convulsive seizures, and these two causes can be impossible to distinguish clinically.

 

Causes of Pediatric Seizures

Pediatric seizures can be caused by:

• fever,
• epilepsy,
• low blood glucose,
• poisoning,
• head trauma, and
• prolonged hypoxia.

 

"Nonepileptic Paroxysmal Disorders of Children"

In the field, there can be many confusing presentations in pediatric patients that don't necessarily mean epilepsy. These are seen as "Nonepileptic Paroxysmal Disorders of Children":

• A sudden loss of tone with or without loss of consciousness may be cardiogenic in origin.
• During a generalized motor seizure, there can be cyanosis.

Although you should consider syncope as a cause for the event if the child is described as pale.

• Consistent crying before a "seizure" is suggestive of a cyanotic breath-holding spell.
• Vagal reactions can cause a color change to pale in infantile syncope; it is a benign syndrome that has a sudden transient bradycardia with collapse and pallor, sometimes followed by an anoxic seizure. Recovery is spontaneous.
• True absence seizures ("petit mal") can't be interrupted by calling the child's name or by stimulation (whereas the staring spells or behavioral inattentiveness commonly seen in children with attention deficit hyperactivity disorder--ADHD--can).

Absence seizures often interrupt a conversation or ongoing physical activity such as eating and play, whereas a pseudoabsence of inattention (or, "daydreaming") tends to occur during more sedentary activity (e.g., sitting at a school desk).

 

In the Field

In the field, newborns can often present with a sudden onset of seizures, even in those born in hospitals who were "checked out" before discharge. Usually, the causes of such surprise neurological findings are:

• Congenital metabolic disturbances due to an abnormal gene or chromosomal expression or mutations, such as hypocalcemia, hypomagnesemia, and hypoglycemia, and other electrolyte and hydration phenomena.
• Dehydration.
• CNS infections.
• Drug withdrawal with neonates exposed to opioids, alcohol, or diazepines in utero.
• Encephalopathy such as porencephaly.
• Hypoxic insult from birth trauma or asphyxiation not discovered immediately.
• Structural brain lesions.

MANAGEMENT:

ABCs: Respiratory failure can result from continuing seizures, so maintenance of airway, breathing, and circulation are imperative.

Other basic EMR management strategies for pediatric seizures include

• the donning of BSI and assuring scene safety.
• Place the patient on the floor and remove any dangerous objects in the area and loosen any restrictive clothing.
• Don't hold the patient down and don't put anything in their mouths.
• After the seizure has ended, put the patient in the recovery position.