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
- Intrathecal Cytarabine
- Intrathecal Methotrexate
- Vincristine (associated with inappropriate ADH and low serum Na)
- Radiation induced damage
- Cerebral necrosis
- Late effect associated with small vessel damage
- Cerebral Abcess
- Metabolic disturbance
- Establish adequate ventilation and circulation
- Lie patient on side
- Establish Airway
- Correct any metabolic abnormality
- Anticonvulsant therapy if the seizure continues
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
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)