6		Flying and Health

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•Only eat properly cooked foods.

•Drink water only from capped bottles or cans.

•Avoid ice cubes made from local water supplies. If in doubt - avoid these altogether.

•When eating together - either on the ground or in flight - each member of the crew should choose a different meal from the menu.

•Allow about a 90 minutes interval between eating and flying. This should be sufficient time for the first symptoms of food poisoning to appear. In addition, some airlines insist that this interval applies to meals of aircrew while in flight.

•Avoid local mayonnaise and ice cream.

The simulator can be of great benefit when training aircrew to recognize and react promptly to incapacitation on the flight deck.

Fits

A fit or seizure is usually referred to as epilepsy. This is not a specific disease but a set of signs or symptoms in response to a disturbance of electrical activity in the brain. Fits are often described as major or minor although the distinction is not always clear.

In a major fit the sufferer may experience convulsions or uncontrolled movements. In a minor fit there may only be a short period of ‘absence’ or loss of attention, similar to daydreaming. Many patients with epilepsy have an abnormal EEG tracing with characteristic signs. An EEG may be used in the initial medical assessment of pilots or applied to pilots who may have had a disturbance of consciousness.

Any fit, major or minor, is associated with an unpredictable loss of consciousness and is therefore an absolute bar to the holding of a flying licence.

Faints

A faint is a common cause of loss of consciousness in adults. The basic reason is a sudden reduction in the blood supply to the brain, commonly caused by:

•Standing up quickly after prolonged sitting, especially when hot or dehydrated.

•A sudden shock or other physiological stressors.

•Loss of blood after an accident.

•Lack of food.

This form of attack has no sinister significance so far as future flying is concerned, as long as the cause is clearly understood.

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Alcohol and Alcoholism

Alcohol

Alcohol (ethyl alcohol or ethanol) is not digested in the human body. It is absorbed directly from the stomach (20%) and intestines (80%) into the bloodstream. From there it is carried to every portion of the body. The liver is responsible for eliminating the alcohol and does this by changing the alcohol into water and carbon dioxide. Drunkenness occurs when the individual drinks alcohol faster than the liver can dispose of it.

Alcohol is broken down by the body at a rate of approximately one unit per hour, though there are many individual differences. (1 unit is approximately half a pint of beer or an imperial glass of wine, or a tot of spirits).

A more accurate measurement is that alcohol is removed from the blood at a rate of approximately 15 milligrams per 100 millilitres per hour. The consumption of 1½ pints of beer or three whiskies will result in a blood/alcohol level of about 45-50 mg/100 ml, and so it can take up to 4 hours for the blood level to return to normal.

The absorption rate into the blood varies, depending on the type of drink (alcohol with fizzy mixes is absorbed much quicker than straight alcohol), body weight, amount of food in the digestive tract and individual metabolic differences. The most important of these is body weight.

Contrary to popular belief, a person cannot speed up the rate at which alcohol is eliminated from the body. The use of black coffee, steam baths or fresh air will not change the rate of oxidation and sleeping off the effects will actually cause the rate of oxidation to be prolonged because body functions and metabolic rates are slowed during sleep. Eating during drinking will only slow the rate at which alcohol is absorbed into the blood, not the amount. It in no way affects the rate at which oxidation occurs.

Once in the bloodstream, alcohol acts as a central nervous system depressant, with some critical areas of the brain (the inhibition centre) being especially vulnerable. Even small amounts of alcohol can, to some degree, produce the following effects:

•Impaired judgement.

•Impaired ability to reason.

•Degraded muscular coordination.

•Lack of inhibition and self-control resulting in increased recklessness.

•Degraded vision.

•Balance and sensory illusions.

•Disrupted sleep patterns (alcohol degrades REM sleep and causes early waking).

•Heightened susceptibility to hypoxia.

•Physical damage to the liver, heart, brain and blood cells.

•Disrupted short and long-term memory.

•Slowed reaction times.

•A false perception that performance has improved.

High altitude, where oxygen is less, worsens these effects.

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Any consumption above the following levels can cause permanent damage to the body:

Men -	Five units daily
	21 units per week
Women -	Three units daily
	14 units per week

Alcoholism

Alcoholism is not easily recognized or defined. The World Health Organization definition is:

“When the excessive use of alcohol repeatedly damages a person’s physical, mental, or social life.”

The single most important characteristic of the alcoholic’s use of drink is a loss of control with a continuing progression to more and heavier drinking or regular binges lasting days or even weeks. The alcoholic does not necessarily present the classic picture of a derelict existing on cheap wine or methylated spirits. Most are supposedly sober citizens with responsible jobs as doctors, lawyers, managers, or even clergy.

No profession is exempt from the illness but some, aircrew in particular, have a higher than average risk because in their occupation they are exposed to factors known to be associated with its development. These include social isolation, boredom, high income, and an easy access to cheap alcohol. Aircrew tend to live in a ‘drinking culture’ with a need to conform and often erroneously use alcohol to unwind and as an aid to sleep.

Signs that may indicate problems with alcohol control are:

•Drinking alone.

•Gulping the first drink.

•Preoccupation with the next drink.

•Becoming defensive and angry when criticized about his/her drinking habits.

•Protection of the alcohol supply.

•Use of alcohol as a tranquilliser.

•Loss of memory of events when drunk.

•Requirement to increase the intake to feel good.

•Morning shakes.

•High tolerance to alcohol.

•Loss of control (binge) drinking.

The alcoholic is a danger to himself/herself and other people. The first essential in the treatment of alcoholism is the admission that he or she is an alcoholic and a willingness to accept treatment.

Total abstinence is the only realistic goal as there is no hope of a return to controlled drinking. Given suitable treatment a pilot can return to flying duties. A high level of social drinking can be damaging, even without alcohol dependence.

Should the suspicion arise that a crew member is suffering from alcoholism, a prompt, frank and positive approach is required with the knowledge that help is available. However, if the direct approach is felt not to be possible, the organization’s aviation medical specialist or fleet manager should be informed.

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Alcohol and Flying

Pilots, in particular, may be exposed to alcohol since during travel alcohol is :

a.always available

b.cheap (duty free)

c.looked upon as a “relaxer” after a long and demanding duty period

d.the tradition of the crew meeting after a flight at the hotel bar

Recent in-flight research has confirmed that even in a small and uncomplicated aircraft, blood/ alcohol concentrations of 40 mg/100 ml (half the legal driving limit) are associated with significant increases in errors by pilots.

EU-OPS specifies a maximum blood alcohol limit for pilots of 20 milligrams per 100 millilitres of blood.

The British authorities have strongly advised that pilots should not fly for at least 8 hours after taking small amounts of alcohol and proportionally longer if larger amounts are consumed. They go on to say that it would be prudent for a pilot to abstain from alcohol for at least 24 hours before flying.

Mixing the consumption of alcohol and drugs is absolutely prohibited as this can lead to disastrous and unpredictable consequences.

Drugs and Flying

Any use of recreational drugs, like alcohol, is incompatible with flight safety. The short-term effects alone are disastrous to intellectual and motor performance. Pilots should also be aware of the dangers of medicinal drugs, particularly the non-prescription “over the counter” type available in chemists and supermarkets.

Caffeine

Caffeine - a central nervous system stimulant - has had a long history in human cultures, yet is one of the drugs which receives relatively little attention. It is, however, the most widely used drug in the world. Because of the lifestyle, aircrews tend to have a comparatively high intake of caffeine compared with other professionals and they should be aware of the dangers.

Its effects on the body, both physiological and psychological, make it evident that caffeine is one of the drugs which may be abused and can lead to addiction. Caffeine is present in coffee, tea, cocoa, chocolate and many fizzy soft drinks such as Coca Cola. Caffeine pills are also available and are sold as an aid to keeping awake and alert. It is also found in medications for dieting, the treatment of colds, allergies and migraines.

A consumption of 6-8 cups of normal strength tea or coffee a day will usually lead to dependence and as little as 200 mg may reduce performance. An average coffee drinker consumes 3.5 cups per day (360 - 440 mg).

For caffeine to be fatal, 10 g or approximately 100 cups of coffee need to be consumed. An intake of 25-30 cups a day is sufficient for the individual to hear odd noises, see flashes of light, exhibit withdrawal symptoms, suffer from extreme nervousness and have an increased heart rate and elevated blood pressure.

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