By Birgit Heitfeld
 
WHEN a passenger in row 16 suddenly turns pale, struggling for breath before slumping into his seat unconscious, the cabin crew has to go into action immediately.
Although medical emergencies in the air are very unusual, on-board medical care is increasingly being recognised as one of the most important problems facing modern airlines.

A rise in total passenger numbers has seen a proportionate rise in the size of so-called high-risk passenger groups, which include babies, the elderly and those in poor health. Airlines are now looking to develop new strategies in order to meet the health requirements of all passengers in their care.
Serious medical problems during a flight often spell an emergency landing and all the additional costs this entails.
Landing fees, hotel accommodation and replacement tickets leave airlines with an annual bill of up to US$220,000.

Britain's Civil Aviation Authority is likely to demand changes too after the recent death of a young woman from a blood clot following a long flight, and a parliamentary committee will urge that airlines give more preventive advice on the condition. The apparently healthy and active 28-year-old woman died after a flight from Sydney to London from DVT, also known as "economy class syndrome'' or "jet leg.''

In 1998, the German carrier Lufthansa had to deal with some 50 life-threatening situations caused by poor passenger health. In 37 cases, the aircraft involved was forced to make an emergency landing. In the United States, four such emergencies are reported in the air every day.

An effective method of dealing with airborne health crises is telemedicine, which enables doctors to treat patients by means of a videophone. Medical equipment such as ultrasound scanners and biomonitors for monitoring heart and circulatory functions are maintained on board.

"These applications have all been adapted from space travel,'' reveals Eduard Mueller, spokesman for the German Aerospace Centre (DLR) in Cologne. The DLR is currently working on a new telemedical system in co- operation with Lufthansa. In the event of an emergency, the crew will contact a specialist at the Tubingen University Clinic who will make a diagnosis and advise treatment from the ground.

In 1985, the American critical care flight nurse Joan Sullivan Garrett founded MedAire in Phoenix, Arizona. The company provides a 24-hour medical hotline for airlines.
MedAire's satellite phone technology means pilots can consult a team of doctors drawn from 16 specialist disciplines. Another 50 specialists can be contacted should the need arise.

In addition to its radio and satellite services, MedAire also provides training for flight crew. The firm puts the number of trainees at approximately 25,000 per year.
The course includes instruction on coping with emergencies caused by variations in passengers' oxygen supply -- the trigger for the majority of in-flight medical problems.
The air pressure within an aircraft cabin is equivalent to that at the top of a 2,500m-high mountain. The change in pressure can pose a risk to those suffering from chronic respiratory complaints who may suffer circulatory collapse and heart failure as a result.