Tutorial 33 - Coma

Question 1

What is the differential diagnosis for a patient in a coma using the “I WATCH DEATH” mnemonic.

Answer 1

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

Question 2

What is the differential diagnosis for a patient in a coma using the “DIMS” mnemonic.

Answer 2

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

Question 3

According to the DIMS mnemonic, how can you identify if there is a “drug” cause of a patient’s coma?

Answer 3

• History
• Toxidrome
• Patient medication list

Question 4

According to the DIMS mnemonic, what can help determine the source of a patient’s coma if you suspect a “infectious” cause?

Answer 4

• examine patient for obvious source: cellulitis/abscess
• Tests to identify the source: urine, imaging
• Gather cultures (start empiric antibiotics in the meantime)

Question 4

According to the DIMS mnemonic, how can you identify if there is a “metabolic” cause of a patient’s coma?

Answer 4

Order appropriate lab studies including TSH where appropriate

Question 5

According to the DIMS mnemonic, what can help determine the source of a patient’s coma if you suspect a “structural” cause?

Answer 5

Consider CT brain

Question 6

What should you do first when an unconscious patient is presented?

Answer 6

ABCs

Question 7

An unconscious patient presents to the ER, and the patients airway is secured and ventilation is established. The patient’s pulses are present. What should be done next?

(4 steps)

Answer 7

1. Obtain vital signs
2. Secure IV access
3. Draw blood for tests
4. check for glucose or signs of opioid overdose

Question 8

An unconscious patient is brought to the ER. Hypoglycemia, opioid overdose, seizures, hypothermia, and heat stroke are ruled out. There is evidence of meningeal irritation, so you suspect either meningo-encephalitis or a subarachnoid hemorrhage and decide to perform a lumbar puncture. What must be done first?

Answer 8

CT brain

You will ALWAYS get a CT before performing an LP on a comatose patient.

Question 9

What is the GCS cut off used to describe severe cases of coma where a patient isn’t able to protect their airway (i.e. can’t protect against secretions or vomit)?

Answer 9

GCS of 8 or less

Question 10

What are some early signs of increased ICP? (x3)

Answer 10

Nausea, vomiting, headache

Question 11

What is Cushings triad, and what is it a positive predictor for?

Answer 11

• Hypertension
• Bradycardia
• Depressed/irregular respiratory pattern

Question 12

What are general considerations for treated a patient with suspected increased ICP?

Answer 12

• 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

Question 13

What are risk factors for an ischemic stroke (CVA)?
OY REVIEW

Answer 13

• A-fib
• previous vascular events
• ↑bp
• DM
• ↑lipids
• older age
• obesity
• smoking
• family history of vascular events
• inactivity
• poor diet