NAC OSCE Emergency Medicine 2

Question 1

A 30-year-old male presents to a Canadian ED after a syncopal episode during exercise. ECG shows a short PR interval and a delta wave. What is the diagnosis and the MOST critical concern?

Accepted Answer

Wolff-Parkinson-White syndrome — risk of rapid conduction during AF causing ventricular fibrillation and sudden cardiac death

Answer

First-degree AV block — benign, no treatment needed

Answer

Brugada syndrome — risk of VF in sleep

Answer

Long QT syndrome — risk of torsades de pointes

Question 2

A 70-year-old patient with COPD presents in acute hypercapnic respiratory failure (pH 7.28, pCO₂ 78 mmHg, SpO₂ 84%). According to Canadian Thoracic Society guidelines, what is the FIRST-line ventilatory support?

Accepted Answer

Non-invasive positive pressure ventilation (NIV/BiPAP)

Answer

High-flow nasal oxygen at 60 L/min

Answer

Immediate intubation and mechanical ventilation

Answer

Controlled low-flow oxygen at 2 L/min only

Question 3

A 22-year-old female presents with right lower quadrant pain, nausea, and a positive urine hCG. Her last period was 7 weeks ago. Transvaginal ultrasound shows no intrauterine gestational sac and free fluid in the pelvis. What is the MOST critical diagnosis to exclude?

Accepted Answer

Ruptured ectopic pregnancy — surgical emergency requiring immediate OB/GYN involvement

Answer

Appendicitis with peritonitis

Answer

Ovarian torsion

Answer

Spontaneous complete miscarriage

Question 4

According to ACLS guidelines used in Canadian hospitals, what is the recommended energy for the first defibrillation shock for ventricular fibrillation with a biphasic defibrillator?

Accepted Answer

120-200 J (biphasic) as recommended by the manufacturer, or 200 J if unknown

Answer

360 J monophasic equivalent for all shocks

Answer

50-100 J as a starting dose

Answer

400 J for better termination of VF

Question 5

A 60-year-old male with known liver cirrhosis presents vomiting large volumes of bright red blood. He is haemodynamically unstable. What is the MOST important immediate pharmacological intervention while awaiting endoscopy?

Accepted Answer

IV octreotide (somatostatin analogue) to reduce portal pressure, plus IV PPI

Answer

IV vasopressin as the only vasoactive agent

Answer

Oral propranolol to reduce portal hypertension acutely

Answer

IV furosemide to reduce ascites and portal pressure

Question 6

A 40-year-old male presents with a severe asthma exacerbation (PEFR <25% predicted, SpO₂ 88%, unable to speak in sentences) not responding to repeated salbutamol nebulisation. What is the NEXT most appropriate escalation?

Accepted Answer

IV magnesium sulphate 2 g over 20 minutes, IV corticosteroids, and prepare for possible intubation or heliox

Answer

Increase salbutamol frequency to every 5 minutes indefinitely

Answer

Oral prednisolone alone and discharge

Answer

Aminophylline IV as first additional agent