CFRN General 4 — Questions and Answers
Question 1: Henry's Law is most clinically relevant to which aeromedical patient concern?
- Expansion of pneumothorax at altitude
- Nitrogen bubble formation in SCUBA divers at altitude (Correct answer)
- Worsening ear pain during descent
- Oxygen toxicity in COPD patients
Correct answer: Nitrogen bubble formation in SCUBA divers at altitude
Henry's Law states that the amount of gas dissolved in liquid is proportional to partial pressure; reduced pressure at altitude causes dissolved nitrogen to come out of solution, risking decompression sickness.
Question 2: A CFRN is called to transport a patient in active labor at 36 weeks gestation. The MOST important assessment prior to accepting the transport is:
- Maternal blood type and crossmatch status
- Estimated fetal weight by fundal height
- Cervical dilation and estimated time to delivery (Correct answer)
- Presence of gestational diabetes diagnosis
Correct answer: Cervical dilation and estimated time to delivery
Cervical dilation and rate of labor progression determine whether there is adequate time to complete transport before delivery, which is the key safety decision in obstetric transports.
Question 3: A flight patient is receiving a vasopressor infusion via IV pump. What altitude-related equipment concern applies?
- Electronic IV pumps are inaccurate above 10,000 feet MSL
- Pump alarms may be inaudible due to rotor noise
- Air entrained in tubing from altitude change can cause air embolism (Correct answer)
- Vasopressors crystallize at low cabin temperatures
Correct answer: Air entrained in tubing from altitude change can cause air embolism
As altitude increases, any air in IV lines can expand and be introduced into the patient; priming lines thoroughly and monitoring for air bubbles is essential during ascent.
Question 4: When calculating medication dosing for a pediatric transport patient, the flight nurse should use which weight-based standard?
- Estimated weight by age in years × 4 + 4 (Leffler formula)
- Standard adult dose divided by patient age
- Broselow tape measurement for weight-based dosing (Correct answer)
- Ideal body weight based on height percentile charts
Correct answer: Broselow tape measurement for weight-based dosing
The Broselow tape correlates patient length to weight and provides pre-calculated drug doses, reducing calculation errors in high-stress pediatric resuscitation situations.
Question 5: A patient with a suspected tension pneumothorax develops severe hypotension and tracheal deviation during flight. The CFRN should:
- Perform immediate needle thoracostomy without waiting for physician order (Correct answer)
- Increase oxygen flow and wait for vital signs to stabilize
- Radio medical control and await orders before any intervention
- Position patient in Trendelenburg and administer fluid bolus
Correct answer: Perform immediate needle thoracostomy without waiting for physician order
Tension pneumothorax is immediately life-threatening; CFRN scope of practice includes needle thoracostomy as an emergency intervention, and delay risks cardiac arrest.
Question 6: Which of the following is the MOST accurate description of the CFRN certification renewal requirement?
- Renewal every 5 years by examination only
- Renewal every 3 years by continuing education or re-examination (Correct answer)
- Renewal annually through employer verification
- No renewal required once initially certified
Correct answer: Renewal every 3 years by continuing education or re-examination
BCEN's CFRN certification is valid for 3 years and can be renewed through continuing education (CE) activities or by retaking the examination.
Question 7: During transport, a patient's SpO2 drops to 82% despite 15 L/min non-rebreather mask. The flight nurse's NEXT intervention should be:
- Switch to nasal cannula to reduce anxiety
- Initiate bag-valve-mask assisted ventilation (Correct answer)
- Increase flight altitude to reduce oxygen demand
- Administer IV sodium bicarbonate for acidosis
Correct answer: Initiate bag-valve-mask assisted ventilation
Failure to maintain adequate SpO2 on high-flow oxygen via non-rebreather indicates the need for assisted ventilation with BVM to improve ventilation and oxygenation.
CFRN General 4
Henry's Law is most clinically relevant to which aeromedical patient concern?