Status Epilepticus

Question 1

What is status epilepticus?

Answer 1

Status epilepticus is a prolonged convulsive seizure lasting for 5 minutes or longer, or recurrent seizures one after the other without recovery in between.

Question 2

What causes status epilepticus?

Answer 2

The cause of status epilepticus are varied. In addition to epilepsy, any neuological insult or systemic abnormality capable of inducing a seizure can theoretically cause status epilepticus.

A common cause of status epilepticus in people with known epilepsy if drug withdrawal due to poor anticonvulsant therapy adherence.

Other common acute causes in adults with or without epilepsy include hypoxia, stroke, metabolic abnormalities and alcohol intoxication or withdrawal. Other less common causes are infection, trauma and tumour.

Question 3

Briefly describe the pathophysiology of status epilepticus

Answer 3

Status epilepticus occurs when mechanisms that abort seizure activity fall. This failure can arise from excessive and abnormally persistant excitation of ineffective inhibition.

Question 4

What are the risk factors for status epilepticus?

Answer 4

• Poor anticonvulsant therapy adherence in people with known epilepsy
• Alcohol use disorder or alcohol withdrawal
• Toxic or metabolic causes such as disturances in water, glucose and electrolyte metabolism
• Process leading to cortical structure damage such as hypoxic-ischaemic brain injury, head trauma, stroke, subarachoid haemorrhage, tumours or brain infections
• Recreational drug use (e.g. cocaine, amphetamines)

Question 5

How do convulsive and non-convulsive status epilepticus differ?

Answer 5

Convulsive status epilepticus

• Prolonged or repeared tonic-clonic seizures with an altered level of consciousness
  
  1. Overt (tonic-clonic, clonic and myoclonic)
  2. Subtle (myoclonic jerks, gaze palsy and head turn)

Non-convulsive status epilepticus

• Altered level of consciousness, confusion or personality change with limited or absent motor findings
  
  1. Absence
  2. Complex partial
  3. Simple partial

Question 6

How does a tonic-clonic seizure present?

Answer 6

Tonic-clonic seizures involve stiffening of the whole body (tonic phase) gradually merging into vigorous shaking (clonic phase).

The patient will typically have their eyes open and be unresponsive to commands in sensory stimuli.

Question 7

What investigations should be ordered for status epilepticus?

Answer 7

• Glucose
• ABG
• Urea
• Creatinine
• LFTs
• Sodium, calcium and magnesium
• FBC
• CRP
• Clotting screen
• Anticonvulsant drug levels

Question 8

How should status epilepticus be assessed?

Answer 8

A-E assessment:

• Secure the airway
• Give high-concentration oxygen
• Assess cardiac and respiratory function
• Check blood glucose levels
• Gain intravenous access (insert a cannula)
• IV lorazepam 4mg, repeated after 10 minutes if the seizure continues
  
  • If seizures persist: IV phenobarbital or phenytoin

Question 9

What is the first-line treatment for status epilepticus in a hospital setting?

Answer 9

Give IV lorazepam first-line; maximum 2 doses (including pre-hospital).

Give IV diazepam if IV lorazepam is unavailable or buccal midazolam if there is no immediate IV access.

Give a second dose if the seizure is not terminated 10-20 minutes after administration of the first dose.

Question 10

What is the second-line treatment for status epilepticus in a hospital setting?

Answer 10

Is seizure continues despite 2 doses of a benzodiazepine (including pre-hospital) give a second-line IV anticonvulsant.

Follow the local protocol. Options include:

• Phenytoin
• Levetiracetam (advice from neuologist)
• Sodium valproate (advice from neurologist)

Question 11

If the patient has ongoing seizures despite treatment with 2 anticonvulsants, what is the next step?

Answer 11

Inform the anaesthetist and neurologist and arrange immediate transfer to intensive care.

Question 12

What is the treatment for status epilepticus in the community?

Answer 12

Give buccal midazolam as first-line treatment. Repeat once 10 minutes later if status continues to threaten.

Give rectal diazepam if preferred of buccal midazolam if not available.

Question 13

What are the complications of status epilepticus?

Answer 13

• Death
• Focal neurological deficits
• Cognitive dysfunction (most notably memory deficits)
• Behavioural problems

Question 14

What differentials should be consdiered for status epilepticus?

Answer 14

• Delirium
• Coma

Question 15

Briefly describe the key diagnostic considerations and management of immediate (0-5 minutes) status epilepticus

Answer 15

Question 16

Briefly describe the key diagnostic considerations and management of early SE (5-20 minutes)

Answer 16

Question 17

Briefly describe the key diagnostic considerations and management of established SE (20-40 minutes)

Answer 17

Question 18

Briefly describe the key diagnostic considerations and management of refractory SE (40-60 minutes)

Answer 18