New Onset Seizures in ED

Seizure is an episode caused by inappropriate electrical discharge from neurone due to imbalance between glutaminergic (excitatory) and γ-aminobutyric acid (inhibitory) activity whereas Epilepsy implies a fixed, more excitatory condition of the brain with a lower seizure threshold. The term epileptic does not refer to an individual a known or reversible cause of seizures.

Types of seizures:

Generalised Seizures: Generally caused by simultaneous activation of the entire cerebral cortex, or originating from a focus and then leading to secondary generalisation. 

Generalized tonic-clonic seizures (grand mal) are the most dramatic type of the generalised seizures where the patient suddenly becomes rigid (tonic phase), trunk and extremities are extended, and the patient falls to the ground. This is followed by rhythmic (clonic) jerking of the trunk and extremities. Patients may appear cyanotic when seizing due to apnea. There is often h/o bowel or bladder incontinence. Following the attack, patient remain in an unconscious state for few minutes. Consciousness returns gradually, and postictal confusion, myal- gias, and fatigue may persist for several hours or more.

Absence seizures (petit man): Classic absence seizures occur in school-age children and are often attributed by parents or teachers to daydreaming or inattention. Brief, generally lasting only a few seconds. Patients suddenly develop altered consciousness but no change in postural tone. They appear confused, detached, or withdrawn, and current activity ceases. They may stare or have twitching of the eyelids. They may not respond to voice or to other stimulation and may exhibit involuntary movements or lose continence. The attack ceases abruptly, and the patients typically resume previous activity without post-ictal symptoms. Similar attacks in adults are more likely to be minor complex partial seizures and should not be termed absence. 

Focal Seizures are more likely to be secondary to a localized structural lesion of the brain. The electrical discharges begin in a localized region of the cerebral cortex and then get secondarily generalised. In simple partial focal seizures, the seizure remains localized, and consciousness and mentation are not affected. In contrast, in complex partial seizures consciousness is affected. Focal seizures are regarded as focal seizures from treatment standpoint. 

Consider developing common protocols between ED and Neurology to expedite management in this subset of patients. 

Key Questions:

• Differentiate between seizure or syncope (Get collateral history if possible) 
• Preceding aura? Sudden v/s Gradual onset ? 
• Focal, Generalised, Focal with secondary generalisation
• Duration, Post ictal confusion, Aura, Any h/o Trauma 
• Past h/o fits (Ask frequency, last follow up, medications, compliance, changes in dose or stressors - sleep deprivation, strenuous activity; infection; electrolyte disturbances; and alcohol or substance use or withdrawal)
• Co-morbidities 
• Medications, Recreational Drug use

Examination:

• Blood Glucose
• Tongue Bite
• Look for other injuries (Head/Spine Injury, Shoulder dislocation)
• Focused Neurological Examination - transient focal deficit following a focal seizure may be seen (Todd’s paralysis)

Investigations

• Known seizure disorder presenting with a single unprovoked seizure -> blood glucose level and AED levels
• New onset seizures -> Blood Glucose, Metabolic profile, Ca, Mg, pregnancy test, and urine tox screen. Seizure driven lactate abnormalities usually clear within 30 minutes 
• LP - in cases of fever, immunocompromised, suspected SAH 
• Obtain imaging (Non-Contrast CT Head) in cases of new onset seizures OR a change in seizure pattern, persistent deficits, fever, recurrent episodes. Because many pathologies may not be evident on initial CT, a follow-up MRI with EEG is frequently done as outpatients 
• Do radiographs or imaging of Spine/Shoulder or other relevant injuries as indicated 

Treatment

• Read more on Status Epilepticus and active seizure management here
• Give Loading dose if already on AEDs and there is h/o being non-compliant
• Adjustment of medication should always be made after discussing with a Neurologist
• Outpatient treatment with AEDs in new onset fits should always be started in liaison with Neurologist 
• Arrange timely follow up and Safety Net (Instruct discharged patients not to to take precautions to minimize the risks for injury from further seizures. Swim, drive, work with hazardous tools or machines, and working at heights)

Patients with provoked (secondary) seizures due to an identifiable underlying condition often require admission and should generally be treated to minimize seizure recurrence

Take Home:

• Differentiate between seizure and other similar pathologies (Migraine, Pseudofits, Syncope)
• Arranging follow up and safety netting is crucial
• Change in AEDs to starting new AEDs should always be done in liaison with Neurologist 

Posted by:

              

     Lakshay Chanana

     

     Speciality Doctor

     Northwick Park Hospital

     Department of Emergency Medicine

     England

     @EMDidactic