Disorders of Conciousness Flashcards
What is the difference between arousal and awareness?
Arousal is the degree of wakefulness
Awareness/alertness is the degree of responsiveness to external stimuli
Define a confused level of consciousness
One that is disoriented in time/place/person
Define a delirious level of conciousness
Disoriented (in space/time/person) + restless/agitated + sometimes hallucinating
What is Obtunded?
Obtunded = reduced alertness + slow responses (awareness)
Present (correct formatting) the GCS score of someone who Obeys commands, is oriented in space/time/person when asked but only opens their eyes to pain?
GCS: 2/4, 5/5, 6/6
Present (correct formatting) the GCS score of someone who flexes their arm to pain, is cussing at you, and opens eyes spontaneously
4/4, 3/5, 3/6
Present (correct formatting) the GCS score of someone who extends their arm to pain, is confused, and opens eyes only to your voice
3/4, 4/5, 2/6
Present (correct formatting) the GCS score of someone who elicits no response to pain and is only mumbling
1/4, 2/5, 1/6
Present (correct formatting) the GCS score of someone who localizes to pain, is not making any sounds and eyes closed unless their is pain.
2/4, 1/5, 5/6
Present (correct formatting) the GCS score of someone who withdraws their arms to pain, is rambling about their sad days.
4/4, 4/5, 4/6
Give 5 intracranial and 5 extracranial causes of reduced conciousness
Intracranial = TBI, stroke, space-occupying lesion, subarachnoid hemorrhage, hematoma, infection (meningitis, encephalitis), Seizures, non-convulsive status epilepticus, Wenicke’s encephalopathy
Extracranial = Cardiac (shock), Resp (Any cause of T1 or T2RF), Renal failure (hypernatremia), endocrine (glucose/thyroid), pH disturbances, alcohol withdrawal, sedatives, poisons and toxins.
Quick history on loss of conciousness
First collateral history going through the course of LOC (before, during, after) including
focal signs before,
seizure activity,
head trauma,
when last seen well
Drug/medication hx with potential for OD/poisoning?
Past psych hx
What are the clinical features of a patient presenting with brain injury?
Reduced GCS: Altered consciousness
Raised ICP: Headache, vomiting, hypertension, bradycardia
Seizures
What part of the ECG is particularly important when suspected of OD?
QT length
When ordering a toxic screen what should you make sure is included other than the typical drugs?
Paracetamol and salicylates as they are one of the most common ODs
What is the first line imaging for all LOC?
Neuroimaging - non-contrast CT
What investigations would you order
If having trouble, its very easy if you ensure youre checking for all your causes
Bedside: Glucose (seizure), urinalysis (UTI), ECG (QRS and QT length imp in OD), ECG (QRS and QT length)
Lab: Bloods (FBC, UandE - renal failure, coag screen -TBI, LFTs (hepatic encephalopathy), Toxic screen (INCLUDE PARACETAMOL and SALICYLATES)
ABG
Blood/urine cultures and viral swabs (sepsis, meningitis and encephalitis) - LP if high suspicion
Neuroimaging: NON-CONTRAST CT (mass effect, hematoma, hemorrhage stroke, TBI)
Endocrine (TFTs)
The general management of LOC is via ABCDE and treatment of the underlying cause. Treat the following underlying causes appropriately with correct dosages and methods of administration.
Hypoglycemia
Hypoglycemia with alcohol abuse history
Infection
Opioid toxicity
Increased ICP (pharmacological dw the rest will come)
Hypoglycemia: IV 50 ml 50% glucose followed by IV 100mg Thiamine
Hypoglycemia with alcohol abuse history: IV 100mg Thiamine followed by IV 50ml 50% glucose
Infection: Antibiotics (Ceftriaxone)
Opioid toxicity: Naloxone
Increased ICP: Mannitol/Hypertonic saline
Most seizures resolve spontaneously within 2 minutes. In an emergency requiring ABCDE approach. How would you manage aside from the typical ABCDE approach.
1) IV thiamine 100mg
2) IV 50% glucose 50ml
3) If longer than 2 minutes: IV Lorazepam (0.1mg/kg max 4mg) can be repeated once. If no IV access Buccal Midazolam (10 mg if >40kg) or Rectal Diazepam (0.2-0.5mg/kg max=20mg) as second line
4) If longer than 5 minutes => ongoing status => Alert anesthetics and ICU where they will administer IV phenytoin/phenobarbitone
5) Refractory Status, nothing is working => General anesthesia (Propofol)
When is a Bag-mask indicated over a non-rebreather mask?
If RR<8
In an emergency situation, when is intubation indicated?
GCS 8 or lower
Many drugs and poisons have a high risk of dysrhythmias. How would you treat it in an acute setting?
4As: Adenosine, adrenaline, amiodarone, and atropine
What is the relation of cerebral blood flow to CO2 and PO2?
Cerebral blood flow increases when CO2 increases => Vasodilation
Cerebral blood flow decreases when PO2 increases => Vasoconstriction
In an emergency situation, it is often essential to get the substance out of the system as quickly as possible. How would you acutely increase elimination?
Gastric/gut lavage
Activated charcoal
and Hemodialysis (in this order)
In terms of poisoning/OD, it is typically difficult or impossible to know the exact substance ingested in an acute setting. In an emergency situation with the ABCDE approach, go through every step
1) Get data from first responders (pre-hospital) and put on PPE to prevent exposure to some
2) Toxidrome-oriented physical examination looking for patterns of signs consistent with groups of agents
3) ABCDE approach
A: Often difficult to keep open reliably => intubation with consideration of rapid sequence intubation (RSI) if needed
B: 100% Non-rebreather mask 15L/min and Bag mask if GCS<8
C: Treat hypotension with fluid bolus IV 500ml normal saline and Vasopressors (norepinephrine, vasopressin).
Treat Dysrhythmias with 4As: Adenosine, adrenaline, amiodarone, and atropine
D: Treat hyperglycemia with 100mg Thiamine IV and 50% 50mg Glucose IV (alcohol suspicion) + Reverse known agents as appropriate (e.g. naloxone 400mg for opioid)
E: Exposure and elimination: Correct hyperthermia with paracetamol and look for any marks, swellings, IV marks for drugs etc…
ELIMINATION: Gastric/gut lavage, Activated charcoal, and Hemodialysis (in this order)
REFERRAL TO TOXBASE
A patient presents in the emergency department with increased HR and BP, high body temp, dilated pupils, no bowl sounds and anhidrosis. What is the most likely group of drugs? Give 2 examples
Anticholinergic: Atropine, antihistamines