Seizure
A seizure is a transient involuntary alteration in consciousness, behavior, motor function, sensory function due to excessive neuronal discharge.
Seizures account for up to 60% of neurological consults on children with cancer.
Causes in Oncology patients
- Underlying malignancy
- primary brain tumor
- metastatic disease to brain
- Meningeal Leukemia.
- Drugs
- Intrathecal Cytarabine
- Intrathecal Methotrexate
- Vincristine (associated with inappropriate ADH and low serum Na).
- Radiation induced damage
- leukoencephalopathy
- cerebral necrosis
- late effect associated with small vessel damage
- Infection
- Meningitis
- Cerebral Abcess
- Metabolic disturbance
- Coagulopathy
Management
- Establish adequate ventilation and circulation
- Lie patient on side
- Establish Airway
- Correct any metabolic abnormality
- Anticonvulsant therapy if the seizure continues
Investigation
When the situation is controlled, it is necessary to:
- Take a history with questions such as
- Is there a previous history of seizures?
- Is there a family history of seizures?
- What medications is the patient taking?
- Have there been any other symptoms?
- Do a physical examination.
- Blood work - CBC. electrolytes (including magnesium, calcium and phosphorus), liver function tests and coagulation screen.
- If there is suspicion of a brain lesion then emergent CT or MR may be appropriate.
Management
Anticonvulsant therapy
If seizure not controlled initially
- Diazepam - (0.2 - 0.5 mg per kg)
- Lorazepam (0.05 - 0.1 mg per kg)
Long term oral control if necessary - phenytoin (20mg per kg)
