EMS EMS Cardiac & Respiratory Emergencies 1 — Questions and Answers
Question 1: A patient presents with sudden-onset chest pain radiating to the left arm, diaphoresis, and nausea. What is the FIRST action?
- Obtain a 12-lead ECG (Correct answer)
- Administer nitroglycerin
- Establish IV access
- Perform a physical exam
Correct answer: Obtain a 12-lead ECG
Obtaining a 12-lead ECG is the highest priority to identify STEMI and activate the cardiac catheterization lab as quickly as possible.
Question 2: Which ECG finding is diagnostic of ST-Elevation Myocardial Infarction (STEMI)?
- ST depression in two or more contiguous leads
- ST elevation ≥1 mm in two or more contiguous leads (Correct answer)
- New left bundle branch block only
- T-wave inversion in V1–V4
Correct answer: ST elevation ≥1 mm in two or more contiguous leads
STEMI is defined by ST elevation ≥1 mm (≥2 mm in V1–V3) in two or more contiguous leads, indicating complete coronary artery occlusion.
Question 3: What rhythm is most commonly associated with sudden cardiac death in adults?
- Asystole
- Pulseless electrical activity (PEA)
- Ventricular fibrillation (VF) (Correct answer)
- Third-degree AV block
Correct answer: Ventricular fibrillation (VF)
Ventricular fibrillation is the most common initial rhythm in sudden cardiac death and is the only shockable rhythm in witnessed arrest.
Question 4: A patient in ventricular tachycardia (VT) with a pulse becomes hemodynamically unstable. What is the treatment?
- Defibrillation at 360 joules
- Synchronized cardioversion (Correct answer)
- Amiodarone IV push
- Adenosine IV bolus
Correct answer: Synchronized cardioversion
Unstable VT with a pulse requires synchronized cardioversion to restore normal sinus rhythm and avoid delivering a shock on the T-wave.
Question 5: How many joules should an AED deliver for the first defibrillation attempt in adult VF?
- 100 J
- 150–200 J (device-specific) (Correct answer)
- 360 J always
- 50 J
Correct answer: 150–200 J (device-specific)
AEDs deliver device-specific energy doses, typically 150–200 J for biphasic devices, which is equally effective to higher monophasic energies.
Question 6: Which finding differentiates pulseless electrical activity (PEA) from asystole on the monitor?
- PEA shows organized electrical activity without a palpable pulse (Correct answer)
- PEA shows a flat line on the monitor
- PEA always shows VF on the monitor
- PEA shows only P-waves without QRS complexes
Correct answer: PEA shows organized electrical activity without a palpable pulse
PEA is defined by organized cardiac electrical activity on the monitor in the absence of a palpable pulse.
EMS EMS Cardiac & Respiratory Emergencies 1
A patient presents with sudden-onset chest pain radiating to the left arm, diaphoresis, and nausea.
What is the FIRST action?