CFRN MCQ 4 — Questions and Answers
Question 1: A flight nurse is transporting a patient with an IABP (intra-aortic balloon pump). Which complication requires IMMEDIATE intervention during transport?
- Balloon trigger switching from ECG to arterial pressure mode
- Loss of helium in the drive line with cessation of counterpulsation (Correct answer)
- Heart rate increase from 70 to 88 bpm
- Diastolic augmentation waveform with a slight change in timing
Correct answer: Loss of helium in the drive line with cessation of counterpulsation
Loss of helium gas and IABP cessation means loss of cardiac support, which is immediately life-threatening in cardiogenic shock.
Question 2: During high-altitude fixed-wing transport, which physiological change directly causes hypoxia despite normal sea-level oxygen saturation?
- Dalton's Law: decreased partial pressure of oxygen despite same FiO2 (Correct answer)
- Henry's Law: decreased oxygen solubility in plasma
- Boyle's Law: lung volume expansion compressing alveoli
- Charles' Law: decreased temperature reducing O2 affinity
Correct answer: Dalton's Law: decreased partial pressure of oxygen despite same FiO2
At altitude, total barometric pressure drops, reducing the partial pressure of oxygen (PO2) even though the fraction of O2 in air (21%) remains constant.
Question 3: A patient with an acute ST-elevation MI (STEMI) is being transported to a PCI center. En route, the patient develops a wide complex tachycardia at 160 bpm with a pulse. What is the MOST appropriate intervention?
- Defibrillate at 200 J biphasic immediately
- Administer lidocaine 1 mg/kg IV and reassess
- Perform synchronized cardioversion at 100 J
- Initiate amiodarone 150 mg IV over 10 min and consider synchronized cardioversion if unstable (Correct answer)
Correct answer: Initiate amiodarone 150 mg IV over 10 min and consider synchronized cardioversion if unstable
Stable wide-complex tachycardia in the setting of STEMI is likely VT; amiodarone is preferred, with cardioversion if the patient deteriorates.
Question 4: Which parameter is the BEST indicator of adequate tissue perfusion in a patient with hemorrhagic shock during transport?
- Mean arterial pressure > 65 mmHg
- Urine output 0.5 mL/kg/hr
- Serum lactate trend toward normalization (Correct answer)
- Heart rate < 100 bpm
Correct answer: Serum lactate trend toward normalization
Lactate clearance reflects resolution of anaerobic metabolism and is the most sensitive marker of restored cellular perfusion.
Question 5: A 28-year-old pregnant patient at 34 weeks gestation is in severe preeclampsia. Which medication is FIRST-LINE to prevent seizure progression?
- Diazepam 10 mg IV
- Phenytoin 15–20 mg/kg IV loading dose
- Magnesium sulfate 4–6 g IV loading dose over 15–20 minutes (Correct answer)
- Labetalol 20 mg IV bolus
Correct answer: Magnesium sulfate 4–6 g IV loading dose over 15–20 minutes
Magnesium sulfate is the standard of care for seizure prophylaxis and treatment in eclampsia/severe preeclampsia.
Question 6: During fixed-wing transport, a patient with a nasogastric tube connected to intermittent wall suction develops increasing abdominal distension and pain. The MOST likely cause is:
- Bowel obstruction worsening in flight
- Trapped gas expanding in the GI tract due to decreased cabin pressure (Correct answer)
- Vagal stimulation from the NG tube causing ileus
- Retrograde air entry from a kinked NG tube
Correct answer: Trapped gas expanding in the GI tract due to decreased cabin pressure
Boyle's Law causes intestinal gas to expand at altitude, worsening distension and discomfort; NG decompression may need to remain open.
Question 7: A flight nurse is called to a scene where a patient has been submerged in cold water for approximately 8 minutes and is pulseless. Which principle should guide resuscitation decisions?
- Terminate resuscitation after 20 minutes of ACLS without ROSC
- The patient should not be declared dead until warm and dead — continue aggressive resuscitation (Correct answer)
- Withhold resuscitation due to prolonged submersion time
- Initiate resuscitation only if core temperature is above 30°C
Correct answer: The patient should not be declared dead until warm and dead — continue aggressive resuscitation
Cold water drowning causes protective hypothermia; the adage 'not dead until warm and dead' mandates resuscitation and rewarming before pronouncing death.
CFRN MCQ 4
A flight nurse is transporting a patient with an IABP (intra-aortic balloon pump).
Which complication requires IMMEDIATE intervention during transport?