OSCE Treatment Protocols & Interventions 5 — Questions and Answers
Question 1: A patient is in ventricular fibrillation. After two defibrillation attempts and CPR, which medication should be given?
- Lidocaine 1.5 mg/kg IV
- Epinephrine 1mg IV every 3-5 minutes (Correct answer)
- Magnesium sulfate 2g IV
- Sodium bicarbonate 1 mEq/kg IV
Correct answer: Epinephrine 1mg IV every 3-5 minutes
Epinephrine 1mg IV every 3–5 minutes is the standard vasopressor for all shockable and non-shockable cardiac arrest rhythms.
Question 2: You are asked to perform a digital nerve block for a finger laceration repair. Which technique is most appropriate?
- Inject 10 mL of 1% lidocaine with epinephrine into the fingertip
- Inject 1–2 mL of plain lidocaine at each side of the finger base (web space block) (Correct answer)
- Apply EMLA cream and wait 60 minutes before suturing
- Perform a Bier block of the entire hand
Correct answer: Inject 1–2 mL of plain lidocaine at each side of the finger base (web space block)
A web space digital block using plain lidocaine (no epinephrine) at the base of the finger effectively anesthetizes a digit for laceration repair.
Question 3: A post-operative patient develops a DVT confirmed by ultrasound. Which anticoagulant is preferred for initial outpatient treatment?
- Unfractionated heparin infusion
- Rivaroxaban 15mg twice daily for 21 days, then 20mg daily (Correct answer)
- Aspirin 325mg daily
- Warfarin initiated immediately without bridging
Correct answer: Rivaroxaban 15mg twice daily for 21 days, then 20mg daily
Direct oral anticoagulants (DOACs) like rivaroxaban are now preferred over heparin/warfarin for DVT treatment in most outpatient settings.
Question 4: A patient with COPD exacerbation presents with PaO2 of 50 mmHg and PaCO2 of 65 mmHg. What oxygen target is appropriate?
- 100% oxygen via non-rebreather mask to maximize saturation
- Titrate oxygen to SpO2 88–92% to avoid hypercapnic drive suppression (Correct answer)
- Withhold oxygen to prevent CO2 retention
- High-flow nasal cannula at 60 L/min
Correct answer: Titrate oxygen to SpO2 88–92% to avoid hypercapnic drive suppression
Titrating oxygen to SpO2 88–92% in COPD exacerbation prevents Haldane effect-driven hypercapnia while treating hypoxia.
Question 5: During a joint aspiration (arthrocentesis) of the knee, the aspirated fluid appears purulent and cloudy. What is the immediate next step?
- Inject corticosteroid to reduce inflammation
- Send fluid for culture, Gram stain, cell count, and glucose; start empiric antibiotics (Correct answer)
- Order an MRI of the knee
- Discharge with NSAIDs and recheck in one week
Correct answer: Send fluid for culture, Gram stain, cell count, and glucose; start empiric antibiotics
Purulent joint fluid is septic arthritis until proven otherwise — send fluid for analysis and start empiric antibiotics immediately.
Question 6: You are treating a patient with hyperkalemia (K+ = 6.8 mEq/L) and peaked T-waves on ECG. What is the FIRST intervention to protect the heart?
- Sodium bicarbonate 50 mEq IV
- Calcium gluconate 1g IV over 2–5 minutes (Correct answer)
- Insulin 10 units IV with dextrose
- Sodium polystyrene sulfonate (Kayexalate) orally
Correct answer: Calcium gluconate 1g IV over 2–5 minutes
Calcium gluconate stabilizes myocardial cell membranes within minutes, protecting against life-threatening dysrhythmias from hyperkalemia.
Question 7: A patient with suspected ectopic pregnancy has a positive beta-hCG of 2,500 mIU/mL but no intrauterine pregnancy on transvaginal ultrasound. She is hemodynamically stable. What is appropriate management?
- Emergency laparotomy
- Methotrexate 50 mg/m² IM if she meets criteria and is followed closely (Correct answer)
- Reassurance and recheck hCG in one week
- Oral mifepristone 200mg
Correct answer: Methotrexate 50 mg/m² IM if she meets criteria and is followed closely
Methotrexate is appropriate for hemodynamically stable patients with ectopic pregnancy who meet specific criteria (no rupture, hCG <5000, no contraindications).
OSCE Treatment Protocols & Interventions 5
A patient is in ventricular fibrillation.
After two defibrillation attempts and CPR, which medication should be given?