EDAIC Emergency Medicine 4 — Questions and Answers
Question 1: In managing a patient with acute ischemic stroke, what is the maximum time window for IV alteplase from symptom onset?
- 3 hours
- 4.5 hours (Correct answer)
- 6 hours
- 24 hours
Correct answer: 4.5 hours
IV alteplase can be administered within 4.5 hours of symptom onset in eligible patients with acute ischemic stroke per current guidelines.
Question 2: A patient in the ICU develops acute respiratory distress syndrome (ARDS). What tidal volume is recommended for lung-protective ventilation?
- 10-12 mL/kg predicted body weight
- 6 mL/kg predicted body weight (Correct answer)
- 8 mL/kg predicted body weight
- 4 mL/kg predicted body weight
Correct answer: 6 mL/kg predicted body weight
The ARDSNet trial established that 6 mL/kg predicted body weight reduces mortality compared to conventional 12 mL/kg ventilation in ARDS.
Question 3: Which antidote is used for acetaminophen (paracetamol) overdose?
- Flumazenil
- N-acetylcysteine (Correct answer)
- Activated charcoal alone
- Methylene blue
Correct answer: N-acetylcysteine
N-acetylcysteine replenishes glutathione stores and is the antidote for acetaminophen toxicity, most effective within 8-10 hours of ingestion.
Question 4: In a patient with diabetic ketoacidosis, when should insulin infusion be started?
- Immediately on diagnosis
- After the first liter of IV fluid
- After potassium > 3.5 mEq/L is confirmed (Correct answer)
- After blood glucose < 250 mg/dL
Correct answer: After potassium > 3.5 mEq/L is confirmed
Insulin should not be started until serum potassium is ≥3.5 mEq/L because insulin drives potassium intracellularly and can precipitate life-threatening hypokalemia.
Question 5: A trauma patient with a Glasgow Coma Scale (GCS) of 8 requires airway management. What is the most appropriate approach?
- Bag-valve-mask ventilation until CT scan
- Nasopharyngeal airway and observation
- Rapid sequence intubation (RSI) (Correct answer)
- Laryngeal mask airway (LMA)
Correct answer: Rapid sequence intubation (RSI)
GCS ≤8 indicates inability to protect the airway and mandates definitive airway management via rapid sequence intubation in trauma patients.
Question 6: What is the mechanism of action of atropine in the treatment of bradycardia?
- Beta-1 adrenergic agonism
- Muscarinic acetylcholine receptor antagonism (Correct answer)
- Inhibition of vagal tone via sodium channels
- Direct sinoatrial node stimulation
Correct answer: Muscarinic acetylcholine receptor antagonism
Atropine blocks muscarinic acetylcholine receptors, reducing vagal tone and increasing heart rate by removing parasympathetic inhibition of the SA node.
Question 7: In eclampsia management, what is the drug of choice for seizure prophylaxis and treatment?
- Phenytoin
- Diazepam
- Magnesium sulfate (Correct answer)
- Levetiracetam
Correct answer: Magnesium sulfate
Magnesium sulfate is superior to phenytoin and diazepam for both prevention and treatment of eclamptic seizures and is the international standard of care.
EDAIC Emergency Medicine 4
In managing a patient with acute ischemic stroke, what is the maximum time window for IV alteplase from symptom onset?