Aeromedical Transport of the Critically Ill

OVERVIEW

• risk to staff and patient
• taking patient into an uncontrolled, hostile environment
• risks of transport has to be weighted up against the benefit offered by facility
• limited space and personnel
• risk with mechanics (helicopter blades, airplane rotors)

ISSUES

General

• must be familiar with: equipment, vehicles, oxygen supply, suction, communication
• gas law: expansion of air filled spaces with altitude
• gas law: decreased partial pressure of O2 with altitude
• some equipment difficult to transport: ECMO, IABP
• electromagnetic interference between avionics and monitoring (defibrillation, pacemaker malfunction).
• noise: unable to auscultate

Airway

• secure endotracheal tube
• measure and monitor cuff pressure (will expand with altitude)
• difficult to perform advanced airway procedures in flight -> decision to intubate should be made on the ground.

Breathing

• decrease in the partial pressure of O2 with altitude (patients on high FiO2 may be compromised)
• expansion of trapped gas (pneumothorax) -> ICD
• decompression sickness
• finite high concentration of oxygen supply

Circulation

• worsening of air embolism
• limb swelling beneath plaster
• take off and landing: haemodynamic instability (long take off and roll out)
• bleeding or body fluid (burns) must be kept to a minimum otherwise damage to mechanics and electrics may mean craft out of action.

Disability

• motion sickness (patients and staff).
• expansion of intracranial air and middle ear.
• patients can become agitated/anxious.

Exposure

• risk of hypothermia
• decompression sickness
• risk of rapid depressurization
• decrease partial pressure of water: risk of dehydration through respiratory losses (passive humidification important)
• ambient noise: auscultation difficult, communication difficult
• limited space, lighting and facilities for intervention
• turbulence, vibration
• danger from loose, mobile equipment