CFRN Cardiovascular Emergencies 4 — Questions and Answers
Question 1: A patient in the flight environment develops pulseless electrical activity (PEA). Which mnemonic best guides the flight nurse in identifying reversible causes?
- AEIOU-TIPS
- DOPE
- The 5 Hs and 5 Ts (Correct answer)
- RSVP
Correct answer: The 5 Hs and 5 Ts
The 5 Hs (Hypoxia, Hypovolemia, Hydrogen ion/acidosis, Hypo/hyperkalemia, Hypothermia) and 5 Ts (Tension pneumothorax, Tamponade, Toxins, Thrombosis-pulmonary, Thrombosis-coronary) guide PEA workup.
Question 2: A CFRN is transporting a patient post-CABG who develops ST elevation in leads II, III, and aVF with reciprocal changes in I and aVL. Which coronary artery is most likely occluded?
- Left anterior descending artery (LAD)
- Left main coronary artery
- Right coronary artery (RCA) (Correct answer)
- Left circumflex artery (LCx)
Correct answer: Right coronary artery (RCA)
ST elevation in the inferior leads (II, III, aVF) with reciprocal depression in I and aVL represents an inferior STEMI, most commonly caused by RCA occlusion.
Question 3: During helicopter transport, altitude-related gas expansion causes which change in a patient who has an untreated pneumothorax?
- The pneumothorax will shrink due to increased atmospheric pressure
- The pneumothorax will expand, potentially converting to tension pneumothorax (Correct answer)
- Gas volume remains unchanged due to the pressurized cabin
- Oxygen absorption reduces pneumothorax size
Correct answer: The pneumothorax will expand, potentially converting to tension pneumothorax
Boyle's Law dictates that as altitude increases and barometric pressure decreases, gas volume expands — a pneumothorax can enlarge and become a tension pneumothorax in flight.
Question 4: A patient with known Wolff-Parkinson-White (WPW) syndrome develops atrial fibrillation during transport with a ventricular rate of 240 bpm. Which drug is absolutely contraindicated?
- Procainamide
- Ibutilide
- Adenosine (Correct answer)
- Amiodarone
Correct answer: Adenosine
Adenosine (and other AV nodal blockers like verapamil, diltiazem, digoxin) are contraindicated in WPW with AF because blocking the AV node forces conduction entirely through the accessory pathway, risking ventricular fibrillation.
Question 5: When calculating mean arterial pressure (MAP), which formula is correct?
- MAP = (SBP + DBP) ÷ 2
- MAP = DBP + 1/3(SBP - DBP) (Correct answer)
- MAP = SBP - DBP × 2
- MAP = SBP × 0.6 + DBP
Correct answer: MAP = DBP + 1/3(SBP - DBP)
MAP = DBP + 1/3(pulse pressure) = DBP + 1/3(SBP - DBP), reflecting that diastole occupies approximately two-thirds of the cardiac cycle.
Question 6: A flight nurse is transporting a neonate with suspected critical congenital heart disease who is cyanotic and not improving with oxygen. Which intervention is most appropriate to maintain ductal patency?
- Indomethacin IV to close the ductus
- Prostaglandin E1 (alprostadil) infusion (Correct answer)
- High-dose furosemide to reduce pulmonary edema
- Phenylephrine to increase systemic vascular resistance
Correct answer: Prostaglandin E1 (alprostadil) infusion
Prostaglandin E1 infusion maintains or reopens the ductus arteriosus in ductal-dependent congenital heart lesions, providing the only source of pulmonary or systemic blood flow.
Question 7: A patient receiving thrombolytics for massive pulmonary embolism develops an acute intracranial hemorrhage during transport. What is the most critical immediate intervention?
- Continue thrombolytics and add anticoagulation
- Discontinue thrombolytics and administer fresh frozen plasma and cryoprecipitate (Correct answer)
- Administer protamine sulfate and continue anticoagulation
- Increase the thrombolytic dose to resolve the embolism faster
Correct answer: Discontinue thrombolytics and administer fresh frozen plasma and cryoprecipitate
Intracranial hemorrhage during thrombolytic therapy requires immediate cessation of the drug and reversal with FFP (replaces clotting factors) and cryoprecipitate (replaces fibrinogen).
CFRN Cardiovascular Emergencies 4
A patient in the flight environment develops pulseless electrical activity (PEA).
Which mnemonic best guides the flight nurse in identifying reversible causes?