Aviation Medicine Flashcards
What is hypoxia? How to recognise and manage it?
- A condition where supply of Oxygen to body’s cells is inadequate
Recognition
- Mild: fatigue, listlessness, lack of concentration
- Moderate: lack of self-criticism, mood changes & confusion, breathlessness
- Severe: cyanosis (blue tinge to fingers & lips), unconsciousness, death
Management
- Provide oxygen at 4L per min (HI)
- Loosen tight clothing around neck, chest and waist
- Monitor pax
What is hyperventilation? How to recognise and manage it?
- Act of rapid / deep breathing most commonly due to anxiety or panic
- Excessive breathing often leaves person feeling breathless
Recognition
- rapid / over breathing
- numbness & tingling of body extremities (pins & needles)
- spasms in hands & feet
- agitation, dizziness, panic
- vision disturbances
- fainting
Management
- Reassure pax with calmness, ask them to take slower but deeper breaths
- Give oxygen at 4L rate (HI)
Gas expansion and the effects (body parts) with altitude?
- The inverse relationship between atmospheric pressure and gas volume affects gases within the body at altitude
- Common body parts affected by gases:
a) Ears
- pressure equalisation is regulated by the Eustachian tube
- if tube is blocked (usually by URTI), ears can experience severe discomfort including pain and lead to possible rupture of eardrums
- symptoms of URTI: cold / flu, sinus or throat infection, hay fever
Recognition
- pax complaining of increasing ear pain during descent
Management
- Instruct pax to chew, yawn or move lower jaw to try and open up bottom end of Eustachian tube
- If unsuccessful, ask pax to perform “Valsalva” manoeuvre by taking deep breath in and closing the mouth. Immediately pinch the nostrils, blow hard and swallow the air; repeat action during descent
- Infants to be encouraged to suck on a bottle or dummy, or allowed to cry vigorously
- If pain persists with descent, apply warmth to outer ear and advise pax to seek medical attention. ** DO NOT USE PAPER CUPS & PLACE OVER EAR
b) Sinuses
- air pockets situated in the facial bones; the narrow canals opening into the nose control pressure equalisation
- blocked sinuses due to cold and infections can cause severe pain with changing pressure i.e. sinus barotrauma
Management
- Instruct pax to blow nose forcibly one side at a time
c) Alimentary canal (bowel)
- gases produced during digestion expand with increasing altitude
- bowel discomfort rarely occurs during in-flight, however the exception is if a cabin decompression event occurs
d) Teeth
- tooth decay (hollow cavity) can affect trapped gases in the body from escaping during ascent; great pressure is applied on the nerve endings causing teeth pain and discomfort
Management
- Apply ice pack to area (constricts blood vessels to limit inflammation & swelling)
- Provide pax with Panadol or aspirin for pain relief if requested
What is decompression sickness? How to recognise and manage it?
- A condition where gas bubble formation occurs in the body as a result of atmospheric pressure changes
- Nitrogen (present in body fluids & tissues) that is forced to leave too rapidly due to the decrease in atmospheric pressure will cause bubble formation in different areas of the body
Recognition
- The Bends = painful joints i.e. elbow, shoulder, hip, wrist, knee, ankle
- The Chokes = pain in chest; dry hacking cough
- The Creeps = itching sensations of the skin, sometimes accompanied by red rash
** other symptoms include “nervous system effects” and “collapse”
Management
- Inform FD to emergency descend
- Administer oxygen
- Keep warm and restrict body movement (prevents air embolism i.e. nitrogen bubbles from moving towards other parts of the body)
- If pax conscious - lie flat; if unconscious - recovery position
- Divert to nearest airport with hyperbaric chamber (for oxygen therapy) and seek medical attention
