21 Jan 2014

Aviation Medicine: Five Strange Health Effects of Flying



Anyone who has ever investigated what it takes to become a military or commercial pilot knows that there are physical health requirements. These include minimum eyesight requirements, standards for cardiovascular function, a medical history free of seizure disorders, and healthy height/weight ratios. However, some prospective pilots may be surprised to learn that an entire branch of medicine has developed as the aviation age has progressed that looks into the effects of flight and spaceflight on the human body.

What is Aviation Medicine?

Aviation medicine (also known as aeromedicine) is a branch of occupational medicine that focuses on the health needs of pilots and passengers that may arise in the hostile environment of flying. Aviation medicine covers a broad range of responsibilities, from ensuring that commercial pilots have sufficient color vision to monitoring the bone and muscle density loss experienced by astronauts.

Just like mechanics and maintenance technicians, aviation medical specialists are part of the chain of accountability that ensures the safety of flight. All aspects of flying have risk associated with them. It’s the duty of those who fly or serve on airplanes to ensure that all risk is kept to an acceptable minimum—and this includes risk from health problems in the flight crew. Aviation medicine specialists need to understand the conditions that exist in airplanes and how these can affect the health and capabilities of pilots.

Who Practices Aviation Medicine?

Aviation medicine specialists fall into two categories: military and civilian. In the armed forces, medical personnel who treat or examine pilots are known as “Flight Surgeons”. These medical personnel have additional training, both in medicine and flight or flying. They may be subject to stricter physical fitness standards than other military medics.

Civilian aviation medical specialists are known as “Aviation Medical Examiners” or “AMEs”, and they are certified by the FAA. They may be regular practicing physicians who provide occasional examinations to people applying for initial pilot licenses. Or they may work for airlines or airports and only handle aviation medicine and pilot exams.

What Aviation Medics Look For

It turns out that there are a lot of potential hazards to health in a flight environment. This may not be obvious to the casual aircraft passenger who is merely grumpy about the lack of leg room.

However, when you consider that the fuselage of the aircraft is all that stands between you and an incredibly cold, deoxygenized and de-pressurized environment, it becomes more apparent that flying presents health risks. Even in today’s pressurized cabins, passengers and flight crew can be affected by three major environmental factors:

Hypoxia – Lack of oxygen. Although oxygen is added back to the air within cabins and flight decks, the content of oxygen is still lower than it would be at ground level. With a loss of cabin pressure, oxygen levels can drop, causing impaired judgement, loss of vision, and, in extreme cases, death. Pilots and passengers who smoke or who take certain prescription drugs may suffer from hypoxia symptoms with even a small loss of oxygen content in the air.

Pressure – The lower air pressure in an aircraft can have an effect on joints, fluids in the blood, and even teeth. Barodontalgia, or “tooth squeeze” is a phenomenon found in pilots and aircraft passengers who experience pain in their teeth or jaws due to differing pressures on the outside and inside of a tooth. Painful sinus blocks, intestinal pains, and headaches can also be caused by differences in pressure.

Dehydration – The moisture level of the air in an aircraft cabin is very low—about 10%-20% humidity. As a result, people breathe out moisture and can’t recover it from the air when they inhale. Dehydration can adversely affect brain reaction times and cause fatigue.

These three factors combined add risk to many kinds of medical treatment. Aviation medicine is another ingenious way science and technology keep us safe while we fly.