Free CFRN Exam Questions That Helps Candidates Pass

Comprehensive and Detailed Explanation:

The correct answer is D because pulseless electrical activity is a nonshockable cardiac arrest rhythm characterized by organized electrical activity without effective mechanical circulation.

Treatment requires immediate high-quality cardiopulmonary resuscitation, appropriate medication administration, and identification of reversible causes.

In this scenario, severe hypoxia following ventilator disconnection is the likely precipitating cause.

Restoring effective oxygenation and ventilation is therefore a critical component of resuscitation.

The team should promptly reconnect or replace the ventilation system, verify endotracheal tube position, and assess chest rise and exhaled carbon dioxide.

High-quality chest compressions should be started without delay, and epinephrine administered according to the cardiac arrest algorithm.

Option A is incorrect because defibrillation is indicated for ventricular fibrillation and pulseless ventricular tachycardia, not pulseless electrical activity. Option B is inappropriate because adenosine does not treat cardiac arrest from hypoxia. Option C delays essential resuscitative measures.

Other reversible causes of pulseless electrical activity include hypovolemia, hydrogen ion excess, potassium abnormalities, hypothermia, tension pneumothorax, cardiac tamponade, and thrombosis.

Continuous waveform capnography may assist in monitoring CPR quality and identifying return of spontaneous circulation.

During aeromedical resuscitation, clear role assignment and minimizing interruptions in compressions are particularly important.

CFRN examination relevance: Tests nonshockable cardiac arrest, reversible causes, airway emergencies, and integrated resuscitation management.

Comprehensive and Detailed Explanation:

The correct answer is B because massive transfusion can cause clinically significant hypocalcemia due to citrate exposure from stored blood products.

Citrate is added to blood components to prevent coagulation during storage. When transfused, citrate binds ionized calcium, temporarily reducing the biologically active calcium concentration in the circulation.

Under ordinary circumstances, the liver metabolizes citrate efficiently. However, rapid transfusion, hypothermia, shock, and impaired hepatic perfusion may reduce citrate clearance.

Severe hypocalcemia can impair myocardial contractility, reduce vascular tone, prolong cardiac repolarization, and contribute to hypotension and dysrhythmias.

Ionized calcium is the preferred measurement for assessing clinically relevant calcium status during massive transfusion.

Intravenous calcium chloride or calcium gluconate may be administered according to clinical protocols, taking into account vascular access, formulation, and patient condition.

Option A is incorrect because citrate-associated hypocalcemia can significantly worsen cardiovascular instability. Option C does not directly restore ionized calcium. Option D is inappropriate because insulin does not treat transfusion-associated hypocalcemia.

The flight nurse should also monitor temperature, potassium, acid-base status, coagulation parameters when available, and the patient's response to resuscitation.

Preventing hypothermia and maintaining balanced hemorrhage resuscitation remain important components of trauma and critical-care transport.

CFRN examination relevance: Evaluates massive transfusion complications, citrate toxicity, ionized calcium monitoring, and electrolyte-focused resuscitation.

Comprehensive and Detailed Explanation:

The correct answer is A because the combination of respiratory compromise, neurological abnormalities, and petechial rash following long-bone fractures is characteristic of fat embolism syndrome.

Fat embolism syndrome most commonly develops after fractures involving the femur, tibia, pelvis, or other marrow-containing bones.

Fat droplets may enter the circulation following trauma and contribute to pulmonary microvascular obstruction, inflammation, endothelial injury, and impaired oxygen exchange.

The syndrome commonly develops within 12–72 hours after injury, although timing varies.

Respiratory manifestations may include tachypnea, hypoxemia, and bilateral pulmonary infiltrates.

Neurological findings can range from agitation and confusion to seizures or coma.

A petechial rash involving the upper torso, axillae, or conjunctivae is a characteristic but inconsistently present finding.

Option B may cause hypoxemia after blunt trauma but does not adequately explain the combined petechial and neurological abnormalities. Option C is inconsistent with the presentation. Option D does not explain the systemic findings.

Management is primarily supportive and includes oxygenation, ventilation when necessary, hemodynamic stabilization, and monitoring for multiorgan dysfunction.

Early stabilization of long-bone fractures is important in reducing complications associated with ongoing tissue injury.

CFRN examination relevance: Tests fat embolism syndrome, delayed trauma complications, and respiratory-neurological assessment.

Comprehensive and Detailed Explanation:

The correct answer is A because static respiratory system compliance describes the relationship between a change in lung volume and the pressure required to produce that change under no-flow conditions.

Compliance is expressed as volume change divided by the corresponding change in distending pressure.

A static compliance of 21 mL/cm H₂O is substantially reduced compared with typical adult respiratory system compliance.

Low compliance indicates that relatively large pressure changes are needed to deliver a given tidal volume.

Common causes include ARDS, pulmonary edema, atelectasis, reduced chest wall compliance, and other restrictive processes.

Option B incorrectly classifies the measurement. Option C is incorrect because static compliance can be estimated using tidal volume, plateau pressure, and total PEEP under appropriate measurement conditions. Option D is incorrect because compliance and airway resistance are distinct mechanical properties that may both be abnormal.

The flight nurse should monitor plateau pressure, tidal volume, PEEP, oxygenation, and patient-ventilator synchrony.

Lung-protective ventilation is especially important when compliance is reduced.

Changes in compliance during transport may indicate progression of pulmonary disease or the development of additional complications.

CFRN examination relevance: Evaluates static compliance, restrictive respiratory mechanics, and lung-protective ventilation.

Comprehensive and Detailed Explanation:

The correct answer is B because hypertrophic pyloric stenosis commonly presents during early infancy with progressive, nonbilious, forceful vomiting after feeding.

The condition involves hypertrophy of the pyloric muscle, producing gastric outlet obstruction.

Affected infants may remain hungry immediately after vomiting because intestinal nutrient delivery is inadequate.

Persistent loss of gastric hydrochloric acid can produce hypochloremic metabolic alkalosis.

Potassium depletion may occur due to vomiting, reduced intake, and renal responses to volume contraction.

The characteristic metabolic abnormalities are important because severe electrolyte disturbances can increase anesthetic and perioperative risk.

Management initially focuses on correcting dehydration and electrolyte abnormalities rather than immediate operative intervention before stabilization.

Definitive treatment is usually surgical pyloromyotomy after adequate resuscitation.

Option A is less consistent because significant diarrheal illness commonly produces bicarbonate loss and metabolic acidosis. Option C more commonly presents with episodic abdominal pain, vomiting, and potentially bloody stools. Option D predominantly affects premature or medically vulnerable neonates and may involve abdominal distention, feeding intolerance, and systemic instability.

The flight nurse should monitor hydration, glucose, electrolytes, perfusion, and ongoing vomiting.

Aspiration precautions and appropriate gastric decompression may also be required.

CFRN examination relevance: Evaluates neonatal gastrointestinal obstruction, metabolic alkalosis, and preoperative stabilization.