Tutorial #33 - Coma Flashcards
What is the differential diagnosis for a patient in a coma using the “I WATCH DEATH” mnemonic.
Infection: Sepsis (UTI, pneumonia, infective endocarditis),
CNS infections
Withdrawal: Alcohol, barbiturate, sedative-hypnotic
Acute metabolic: Electrolyte disturbance, hepatic failure, renal failure, acidosis, alkalosis
Trauma: Head injury, postoperative, severe burns
CNS pathology: stroke, intracranial hemorrhage, seizures, cerebral vein thrombosis, tumors/metastases, hydrocephalus, vasculitis, encephalitis, meningitis, syphilis
Hypoxia/Hypotension: cardiac or pulmonary dysfunction (CHF or PE), anemia, carbon monoxide poisoning
Deficiencies: Vitamin B12, thiamine
Endocrinopathies: Hyper / hypoglycemia, hyper / hypoadrenocorticism, myxedema, hyperparathyroidism
Acute vascular: Hypertensive encephalopathy, stroke, arrhythmia, shock
Toxins or drugs: Prescription drugs, illicit drugs, pesticides, solvents, environmental exposure
Heavy Metals: Lead, manganese, mercury
What is the differential diagnosis for a patient in a coma using the “DIMS” mnemonic.
Drugs (therapeutic, intoxication or withdrawal):
Prescription medications, illicit drugs, pesticides, solvents, environmental/heavy metal exposure, post-anesthesia, alcohol (intox or withdrawal), sedative hypnotic (intox or withdrawal),
Infection/inflammation: Sepsis, CNS infections (meningitis/encephalitis), vasculitis, syphilis, rheumatological (i.e. lupus cerebritis), post- operative
Metabolic: electrolyte disturbances, organ failure (cardiac, hepatic, renal), endocrinopathies (thyroid, glucose), vitamin deficiencies (B12, thiamine)
Structural (“brain” problem): trauma, stroke, ICH, hydrocephalus, seizures, tumors, hypertensive encephalopathy
According to the DIMS mnemonic, how can you identify if there is a “drug” cause of a patient’s coma?
- History
- Toxidrome
- Patient medication list
According to the DIMS mnemonic, what can help determine the source of a patient’s coma if you suspect a “infectious” cause?
- examine patient for obvious source: cellulitis/abscess
- Tests to identify the source: urine, imaging
- Gather cultures (start empiric antibiotics in the meantime)
According to the DIMS mnemonic, how can you identify if there is a “metabolic” cause of a patient’s coma?
Order appropriate lab studies including TSH where appropriate
According to the DIMS mnemonic, what can help determine the source of a patient’s coma if you suspect a “structural” cause?
Consider CT brain
What should you do first when an unconscious patient is presented?
ABCs
An unconscious patient presents to the ER and thier ABCs are fine (i.e. airway patent, breath sounds fine, pulses good).
- Obtain full vital signs
- Check glucose
- Secure IV access
- Investigations (bloodwork, ECG, etc)
- Assess/treat for immediately reversible causes (i.e. opioid intox, hypoglycemia, Wernicke’s)
An unconscious patient is brought to the ER. Thier vital signs are normal other than a temperature of 39 degrees. Their eyes remain closed even to painful stimuli, they are non-verbal, and they are withdrawing to pain. There is no obvious toxidrome, and the rest of thier exam is unremarkable other than neck stiffness. Thier glucose is checked and is normal.
1. What is this patient’s GCS?
2. What is the most likely diagnosis?
3. What is the next investigation/test you should do and why?
- GCS=E1V1M4 = 6
- CNS infection such as meningitis
- CT brain, because a space occupying lesion/high ICP needs to be ruled out before LP. If CT normal, then LP is next.
Remember, CT before LP in:
- Altered mentation
- Focal neurologic signs
- Papilledema
- Seizure within the previous week
- Impaired cellular immunity
- Trauma
What is the GCS score where a patient’s ability to manage thier airway is compromised (i.e. sometimes used as trigger to intubate?)
GCS of 8 or less
What are some early signs of increased ICP? (x3)
Nausea, vomiting, headache
What is Cushings triad, and what is it a positive predictor for?
- Hypertension
- Bradycardia
- Depressed/irregular respiratory pattern
What are general considerations for treated a patient with suspected increased ICP?
- keeping cerebral perfusion pressure (MAP-ICP) >60
- ICP <20
- good oxygenation
- normal blood glucose.
- BP: targets vary depending on underlying pathology and on the patient’s normal BP range
What are risk factors for an ischemic stroke (CVA)?
- A-fib
- previous vascular events
- ↑bp
- DM
- ↑lipids
- older age
- obesity
- smoking
- family history of vascular events
- inactivity
- poor diet
An unconscious patient is brought to the ER. Thier vital signs are normal other than a resp rate of 6. Their eyes open to painful stimuli, they are making noise but not words, and they are localizing pain. They have pinpoint pupils, and you notice track marks to their arms. The rest of thier exam is normal. Thier glucose is checked and is normal.
1. What is this patient’s GCS?
2. What is the most likely diagnosis?
3. What should be your step?
- GCS = E2V2M5 = 9
- Opioid overdose
- Treat with naloxone (route - intravenous, intramuscular, intranasal)
