Tutorial #33 - Coma Flashcards
(57 cards)
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, what is next step if you suspect drug is causing coma (x3)?
- 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 (x3)?
- 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
Next steps (x5)?
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
Indicative of increased ICP
What are general considerations for treated a patient with suspected increased ICP (x5)?
- 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
Note high ICP is not end diagnosis, something is causing it
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
Basically all the vascular risk factors
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)
An unconscious patient is brought to the ER. Thier vital signs include a BP of 190/110, RR 12 and irregular. Their eyes open to voice, they are making nonsensical words, and they are flexing with painful stimuli. They have assymetric pupils R=4mm and L=2mm. The rest of thier exam is normal. Thier glucose is checked and is 4.1 (normal is 4.0–11.0 mmol/L).
1. What is this patient’s GCS?
2. What is the most likely diagnosis?
3. What should be your step?
- GCS= E3V3M3 = 9
- Intracranial hemorrhage - they have cushing’s triad, and assymetric pupils can be a sign of herniation!
- Urgent CT. Yes, the glucose is borderline low, but it’s not the cause of the decreased LOC!
What are 3 risk factors for non-traumative intracranial hemorrhage?
- coagulation disorder/anticoagulant use
- elderly
- hypertension
What are positive (x6) and negative (x1) predictors for hypertensive encephalopathy?
Positive predictors:
Severe hypertension.
Acute confusion.
Visual changes,
papilledema and
retinal changes.
MRI sometimes shows reversible posterior leukoencephalopathy syndrome (aka PRES syndrome).
Negative predictors:
BP < 180/120 (basically rules it out)
What is the triad of Wernicke’s Encephalopathy?
The classic triad of WE is: confusion, staggering gait, and oculomotor abnormalities.
(WACO -> Wernicke = Ataxia, Confusion, and Ophthalmoplegia)
(Like Waco, Texas)
Hypotension and hypothermia may also be present.
What are positive/negative predictors for psychogenic coma?
Positive predictors:
Normal physical exam,
resisting eye opening,
normal reflexes,
normal plantar response.
Normal nystagmus response to ice-water caloric testing. (Basically completely normal physical)
Negative predictors:
presence of any objective abnormality (not counting muscle tone) makes the diagnosis unlikely or even ruled-out.
Ability to maintain posture suggests a catatonic state (which is a different entity)
What does the I in I WATCH DEATH stand for?
Infection (UTI, bac men, pna, etc.)
What does the W in I WATCH DEATH stand for?
Withdrawal (barb, sed-hyp, etoh)
What do the two As in I WATCH DEATH stand for?
Acute metabolic (lytes, hep failure, renal failure, etc.)
Acute vascular (stroke, shock, HTN encephalopathy, etc.)
What do the two Ts in I WATCH DEATH stand for?
Trauma (Burns, post-op, head injury, etc.)
Toxins/Drugs (solvents, illicit drugs, etc.)
