Convulsion

A convulsion is an episode of neurologic dysfunction caused by abnormal neuronal activity that results in sudden change in behavior, sensory perception, or motor activity. For a patient with new onset convulsion the list of possible causes is longer and consists of the following:

• CNS pathologies (stroke, neoplasm, trauma, hypoxia, vascular abnormality)
• Metabolic abnormalities (hypoglycemia/hyperglycemia, hyponatremia/hypernatremia, hypercalcemia, hepatic encephalopathy.
• Toxicological etiologies (alcohol withdrawal, cocaine, isoniazid, theophylline) 
• Infectious etiologies(meningitis, encephalitis, brain abscess, neurocycticercosis and malaria.

Approach to a patient 

• Ask for history of epilepsy, if yes; compliance to anticonvulsant
• History of CNS pathology(stroke, neoplasm, recent surgery)
• History of systemic neoplasms, infections, metabolic disorders, or toxic ingestions
• Recent trauma or fall
• Alcohol abuse
• Trauma
• Eclampsia 
• Intracranial hemorrhage
• Alcohol or medication withdrawal (barbiturate, diazepam) 
• Drug induced seizures(tricyclic antidepressant and isoniazid overdose)

Laboratory studies

• Clinical information should guide the specific workup of a patient. Some investigations must be ordered:
• Serum glucose level 
• Serum electrolyte 
• Pregnancy test for women of child bearing age
• CT scan is indicated as outpatient/inpatient depending on progress of patient after episode of seizure. For a patient who had previously history of seizure do CT scan brain if;

• New focal deficits 
• Trauma 
• Persistent fever
• New character or pattern to the seizure

ECG should be considered in some patients. Seizure event can be precipitated by cerebral hypo-perfusion due to arrhythmia, ECG may identify the following

• Prolonged QTc 
• Widened  QRS 
• Prominent R in aVR 
• Heart block

Consider Lumbar Puncture in; 

• Immune-compromised
• Persistent fever 
• Severe headache 
• Persistently altered mental status

Treatment and management

Neurological dysfunction is theorized to occur after 20mn of continuous seizure, so aggressive treatment of any seizure should be done in 5 min. always consider the underlying cause until proved otherwise.

1. A, B, C (airway, breathing, circulation) 
2. Benzodiazepines 

A: Diazepam 10-20mg IV at a rate of 0.5ml (2.5mg) per 30 sec. Repeat if necessary after 30-60min. May be followed by intravenous infusion to max. OR 3mg/kg over 24 hours, per rectum 500mcgrms/kg up to max of 30g)

B: Phenytoin 18mg/kg IV stat then 100mg 8 hourly O/IV

C: Phenobarbitone 20mg/kg 8 hourly. Max. Dose 1.5g

References

https://en.wikipedia.org/wiki/Convulsion
https://www.medicalnewstoday.com/articles/324330
https://www.webmd.com/first-aid/convulsions-in-children
https://medlineplus.gov/ency/article/003200.htm
https://www.researchgate.net/publication/216226860_Basics_of_Convulsive_Disorders_Febrile_Seizures
https://www.epilepsysociety.org.uk/sites/default/files/attachments/Chapter08Verity2015.pdf
https://www.sciencedirect.com/topics/medicine-and-dentistry/convulsion
https://jamanetwork.com/journals/jamapediatrics/fullarticle/495848
https://www.sciencedirect.com/topics/medicine-and-dentistry/convulsion