CFRN Cardiovascular Emergencies 5 — Questions and Answers
Question 1: A flight nurse is transporting a patient with a suspected right ventricular infarction (RVI). Which intervention is most harmful in this patient?
- IV normal saline bolus 500 mL
- Nitrates for chest pain relief (Correct answer)
- Dopamine for hemodynamic support
- Right-sided ECG lead placement
Correct answer: Nitrates for chest pain relief
Nitrates cause venodilation and preload reduction, which is extremely dangerous in RVI because the right ventricle depends on adequate preload to maintain cardiac output.
Question 2: During transport, a patient develops third-degree (complete) AV block with a ventricular escape rate of 28 bpm and hypotension. The transcutaneous pacemaker fails to capture. What is the pharmacologic bridge therapy?
- Adenosine 6 mg IV push
- Atropine 1 mg IV (repeat up to 3 mg)
- Epinephrine infusion 2–10 mcg/min (Correct answer)
- Verapamil 2.5 mg IV
Correct answer: Epinephrine infusion 2–10 mcg/min
In complete heart block with a slow ventricular escape below the His-Purkinje system, atropine is ineffective; epinephrine (or dopamine) infusion is used as a bridge when transcutaneous pacing fails.
Question 3: A CFRN calculates a patient's cardiac output (CO) using the Fick principle. If oxygen consumption (VO2) is 250 mL/min and the arteriovenous oxygen difference (avDO2) is 5 mL/dL, what is the cardiac output?
- 1.25 L/min
- 5.0 L/min (Correct answer)
- 12.5 L/min
- 2.5 L/min
Correct answer: 5.0 L/min
CO = VO2 ÷ avDO2 = 250 mL/min ÷ 50 mL/L (5 mL/dL × 10 dL/L) = 5.0 L/min, which is normal.
Question 4: A patient with dilated cardiomyopathy and an ejection fraction of 20% is being transported. Which finding would most indicate worsening acute decompensation requiring emergent intervention?
- Mild peripheral edema unchanged from baseline
- SpO2 of 88% with respiratory distress and frothy sputum (Correct answer)
- Heart rate of 88 bpm in normal sinus rhythm
- BNP level of 400 pg/mL
Correct answer: SpO2 of 88% with respiratory distress and frothy sputum
SpO2 88% with respiratory distress and frothy (pink) sputum indicates acute pulmonary edema from severely decompensated heart failure requiring immediate intervention.
Question 5: Which lead configuration is most sensitive for detecting ST changes associated with left anterior descending (LAD) artery occlusion during continuous cardiac monitoring in flight?
- Lead II
- Lead V1
- Lead V5 or MCL5 (Correct answer)
- Lead aVR
Correct answer: Lead V5 or MCL5
Lead V5 (or its modified equivalent MCL5) overlies the lateral precordium and is most sensitive for detecting anterior and lateral wall ischemia from LAD territory involvement.
Question 6: A patient with Brugada syndrome is being transported after an episode of syncope. Which environmental factor during flight can precipitate a life-threatening arrhythmia in this patient?
- Increased ambient light exposure
- Fever from an untreated infection (Correct answer)
- High-altitude-induced hypocapnia
- Noise-induced sympathetic activation
Correct answer: Fever from an untreated infection
Fever is a well-known trigger for unmasking Brugada syndrome and can precipitate ventricular fibrillation — temperature management is critical in these patients.
Question 7: A flight nurse is preparing to perform emergency pericardiocentesis for cardiac tamponade. Which approach and landmark is used for needle insertion in the subxiphoid (parasternal) technique?
- 2nd intercostal space, left midclavicular line, angled toward the right shoulder
- Just below and left of the xiphoid process, needle angled at 45° toward the left shoulder (Correct answer)
- 4th intercostal space, right parasternal border, needle perpendicular to chest wall
- Just below and right of the xiphoid, needle angled straight posteriorly
Correct answer: Just below and left of the xiphoid process, needle angled at 45° toward the left shoulder
The subxiphoid approach inserts the needle just below and to the left of the xiphoid process at a 45° angle directed toward the left shoulder to enter the pericardial sac.
CFRN Cardiovascular Emergencies 5
A flight nurse is transporting a patient with a suspected right ventricular infarction (RVI).
Which intervention is most harmful in this patient?