Decreased Level of Consciousness
Level Of Consciousness – AVPU (Alert, respond to Verbal, respond to Pain, Unresponsive)
1. In a patient presenting with altered level of consciousness (LOC), develop an appropriately broad differential diagnosis (e.g., metabolic, infectious, structural, medications, recreational drugs, postictal) while promptly ruling out the serious possible causes (e.g., intracranial hemorrhage/thrombosis, meningitis/encephalitis, toxins).
- Drug: alcohol, opiates, poisons
- Infection: septic shock, encephalitis
- Metabolic: diffuse brain dysfunction
- Endocrine, electrolytes, insulin (hypoglycemia), uremia, adrenal crisis
- Environment: oxygen (hypoxia), temperature (hypo or hyperthermia)
- supratentorial – bilateral cerebral
- Infratentorial – reticular activating system – brainstem
- Diffuse – Seizure, intracranial hypertension
- Non-convulsive status epilepticus can present as coma – EEG to r/o
2. In a patient with altered LOC, treat reversible causes promptly (e.g., hypoglycemia, hypoxia, opioid intoxication, hypotension/hypovolemia).
- ABC + BG & coma cocktail: dextrose, oxygen, naloxone, thiamine
- consider flumazenil and fomepizole
- C – spine if trauma
- Inspect signs of alcohol, drugs, toxic exposure
- GCS / Pupils / reflexes / fondoscopic exam & motor
- Labs: CBC, lytes, glucose, ABG, tox screen, EtOH
- CT head
Bilateral miosis ddx
- Pontine stroke
- cerebral lesions look toward lesion and away from paralysis
- brainstem look away from the lesion and paralysis
Acute visual issues
- Glaucoma – mid range pupil
- PCA stroke – nystagmus
- Temporal arteritis – vision loss
- Botulism – ophthalmoplegia
- Myasthenia gravis – ptosis
- Multiple sclerosis – internuclear ophthalmoplegia
- pseudotumor cerebri – papilledema
3. In a patient presenting with altered LOC, actively seek collateral/pre-hospital history and confirm the nature of the change in LOC from the patient’s baseline.
4. When a patient presents with a decreased LOC, do not accept a minor diagnosis (e.g., alcohol intoxication) as a cause without having eliminated other potential serious causes (e.g., head trauma).
EtOH patient with dec LOC – CT head to r/o ICB
5. In a patient with altered LOC, use both qualitative and quantitative descriptors to document the degree of decreased LOC and to monitor the trend in level over time (e.g., Glasgow Coma Scale).
GCS – meant to use in trauma
- Eye Opening: 4-spontaneous 3-verbal 2-pain 1 – none
- Verbal: 5-oriented, 4-confused – able to answer questions, 3- inappropriate response / words 2- incomprehensible, 1-none
- Motor: 6 – spontaneous, 5 – localized, 4 – withdrawal, 3 – flexion / decorticate, 2 – extension / decelebrate, 1 – none