CFRN flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Dalton's law

Total atmospheric pressure equals the sum of partial pressures; at altitude, lower barometric pressure reduces inspired oxygen partial pressure even when FiO2 is unchanged.

Boyle's law

At constant temperature, gas volume is inversely proportional to pressure; trapped gases expand as cabin altitude rises, risking pneumothorax, endotracheal cuff overinflation, and bowel distension.

Henry's law

The amount of dissolved gas is proportional to its partial pressure; rapid ascent can release nitrogen bubbles, causing decompression sickness in unpressurized flight.

Alveolar gas equation

PAO2 equals FiO2 times barometric pressure minus water vapor pressure, minus PaCO2 divided by respiratory quotient; it estimates alveolar oxygen.

Cabin altitude

Equivalent pressure altitude inside a pressurized aircraft, usually 6,000-8,000 ft; pressurization failure raises it and requires oxygen and descent.

Positive pressure ventilation effects

Positive-pressure ventilation increases intrathoracic pressure, reduces venous return and cardiac output, and can cause hypotension, especially with hypovolemia; monitor blood pressure during transport.

Hypoxia signs

Tachycardia, confusion, agitation, cyanosis, and altered mental status; pulse oximetry may lag and is unreliable with poor perfusion or carbon monoxide.

Shock index

Heart rate divided by systolic blood pressure; an adult value above 0.9 suggests occult shock and the need for rapid assessment and resuscitation.

Primary survey ABCDE

Airway, breathing, circulation, disability, and exposure; life threats are identified and corrected before the secondary survey and transport.

Parkland formula

For burns, 4 mL/kg/% total body surface area lactated Ringer's in 24 hours; half is given in the first 8 hours from burn time.

Pediatric hypotension

Systolic blood pressure below 70 plus twice age in years for children 1-10; infants below 70 mm Hg; indicates decompensated shock.

ET cuff pressure

Target 20-30 cm H2O; cuff pressure rises with altitude because gas expands, so monitor and adjust to avoid tracheal ischemia.

Stroke thrombolysis window

Intravenous alteplase may be given up to 3 to 4.5 hours from last known well in eligible patients; check glucose and contraindications.

Traumatic brain injury transport

Avoid hypoxia and hypotension; maintain systolic blood pressure at least 90 mm Hg and adequate oxygen saturation because secondary injury worsens outcomes.

Crew resource management

Team training using briefings, assertiveness, shared mental models, and closed-loop communication to reduce human error during transport.

Sterile cockpit rule

Nonessential conversation and distractions are avoided during critical flight phases such as takeoff, landing, and emergencies to maintain safety.

Safety management system

Formal framework with four pillars: safety policy, risk management, assurance, and promotion; supports proactive hazard identification and continuous improvement.

Just culture

Balances nonpunitive reporting of errors with accountability for reckless behavior; encourages disclosure and learning from safety events.

Closed-loop communication

Sender gives an order, receiver repeats it back, and sender confirms; reduces misunderstanding in noisy or high-stress transport environments.

Go/no-go decision

Structured risk assessment of weather, aircraft, crew, patient, and terrain; any unacceptable risk can cancel or delay transport.

Oxygen cylinder duration

Approximate duration in minutes equals cylinder capacity in liters divided by flow rate in liters per minute; account for altitude and reserve.

Landing zone size

Helicopter landing zone commonly at least 100 by 100 feet in daylight and larger at night; clear debris and identify approach and departure paths.

Weight and balance

Aircraft center of gravity and maximum weight must remain within limits; patient, crew, fuel, and equipment weights are included before flight.

Lithium battery transport

Spare lithium batteries must be carried in cabin, protected from short circuits, and kept within state-of-charge limits; damaged batteries are not transported.

Electromagnetic interference

Electrical devices such as radios and phones can disrupt monitors, pumps, and aircraft systems; maintain distance and use approved equipment.

Ventilator at altitude

Gas volume changes with pressure and temperature; transported patients need tidal volume and alarms verified because displayed volumes may differ from delivered volumes.

Informed consent elements

Valid consent requires patient capacity, adequate information about risks and alternatives, and voluntariness; emergency exceptions exist when a life threat is present.

EMTALA transfer requirements

Hospitals must stabilize emergency conditions and provide an appropriate transfer with an accepting physician, qualified transport, and records; patient dumping is prohibited.

SBAR handoff

Situation, Background, Assessment, and Recommendation; structured communication improves transfer of critical patient information between crews and receiving teams.

Scope of practice

Duties permitted by state law, licensure, and medical director protocols; flight nurses must function within these limits during transport.

HIPAA minimum necessary

Disclosures for treatment, payment, or operations should use the least protected health information needed for the purpose.

Refusal of care

A patient with decision-making capacity may refuse; document informed refusal, risks, alternatives, and medical control consultation when required.