Neuro Core Conditions 2 Flashcards
How is Status Epilepticus defined?
Either:
Single seizure persisting >30mins
Multiple seizures of shorter duration without a full neuro recovery in between
What is the pathophysiology of a seizure?
Rapid abnormal electrical discharges from cerebral neurones.
Arise from an imbalance between excitatory & inhibitory neurotransmitters (GABA & Glutamate)
Leading to failure of inhibitory process
What are the signs & symptoms of a prolonged seizure?
Tachycardia Hypertension Hyperglycaemia Lactic acidosis >30mins: Cerebral auto regulation & perfusion impairment From surge of catecholamines
What are the causes of status epilepticus?
1/3: Chronic epilepsy
1/3: New onset epilepsy
1/3: No past/future epilepsy
Other: OH/drug withdrawal, Stroke, SAH, CNS infection
How is a seizure investigated?
Bloods: U&E, FBC, LFT, Mg, Ca, Glucose, clotting, drug levels Blood cultures Depending on situation: CT Brain CXR (aspiration) LP EEG- In acute setting- Refractory S.E
How is status epilepticus managed?
STAGE 1: EARLY STATUS 0-10mins
- Secure airway & 15L/min Oxygen
- IV access & assess CV function
- IV Lorazepam 4mg bolus repeated at 10mins
STAGE 2: 0-30mins
- Glucose (50ml of 50%) +/- IV Thiamine if OH- abuse
- IV Phenytoin 15-18mg/kg at 50mg/min alt Phenobarbital or Fosphenytoin
- Monitor ECG
STAGE 3: ESTABLISHED 0-60mins
-Call ITU/ anaesthetist
STAGE 4: REFRACTORY: 30-90mins
- ITU transfer w/EEG monitoring
- GA with one of the following: 1-2mg/kg bolus Propofol, Thiopentone, Midazolam
- Anaesthetic continued for 12-24hrs after last seizure effect
What are the causes of epilepsy?
Primary generalised epilepsy Developmental abnormalities Brain trauma & surgery Intracranial mass/lesion CNS infection Metabolic disturbance Vascular abnormalities Pyrexia in children Drugs: Lidocaine, Ciclosporin, Lithium, Cocaine, OH withdrawal
What are the triggers for a seizure in epilepsy?
Sleep deprivation Alcohol (intake & withdrawal) Drug misuse Physical/mental exhaustion Flashing lights (PGE only) Infection/metabolic disturbance
How is partial epilepsy classified?
Simple partial: JACKSONIAN, Normal consciousness, isolated limb jerking/head turning away from seizure, isolated parasthesia, Todd’s paralysis
Complex partial: May impair consciousness, lip smacking, tachy, emotional disturbance, drowsy after, Déjà vu, vertigo, hallucinations, automatism
Secondary generalised: Partial that becomes general, tonic-clonic
How is generalised epilepsy classified?
Brainstem/ midbrain
Absence: PETIT MAL, childhood onset, unresponsive but conscious, staring, pale, some muscle jerking, multiple attacks on the same day, can affect school, normal after attack, likely to develop tonic-clonic later in life, generally <15s
Tonic-Clonic: GRAND MAL, aura, Tonic 10-60s: tongue biting, rigid, incontinence, hypoxic/cyanotic, epileptic cry, Clonic: secs-mins, eye rolling, tachy, convulsions, no/random breathing, usually self-limiting, headache afterwards
Tonic
Myoclonic: Clonic symptoms only
Atonic: Looks like fainting
How is epilepsy diagnosed?
ECG Neuro exam Bloods: Ca, Glucose, U&Es, LFTs, CK, Prolactin CT/MRI/PET scan EEG Sleep recordings/ 24hr EEG
How is epilepsy managed?
Inform DVLA
Partial: 1) Carbamezepine, 2)Sodium Valproate, Phenytoin
Generalised: 1) Sodium Valproate, 2) Lamotrigine
Absence: Sodium Valproate
Myoclonic: Sodium Valproate
What are the causes of a stroke?
Cerebral infarction 85% (ischaemic stroke)
Primary haemorrhage
Subarachnoid haemorrhage
What are the causes of cerebral infarction?
Large artery atherothromboembolism
Small vessel disease
Embolism from cardiac source
Which arteries would be affected in stroke if:
- Leg > arms affected
- Greatest deficit in the face & arms
- Legs: Anterior cerebral artery
- Face: Middle cerebral artery
