Air Travel - Health Issues
In-Flight Problems
Dehydration
The circulating air in aircraft cabins is dry since there is very little moisture in the air taken from outside the cabin to replenish supplies when the planes are at high altitude. Skin moisturizers can help alleviate dry skin and lips and if contact lenses irritate they should be removed and spectacles used instead if necessary.
There is no evidence that the dry air results in significant internal dehydration in those otherwise fit and well. Alcohol (especially spirits) and caffeine containing drinks can however cause dehydration especially when inadequate clear fluids are drunk - passengers should try and drink sufficient to keep the urine its normal pale colour.
Poor Circulation
Sitting still for long periods in the inevitably cramped positions in aircraft frequently leads to swollen ankles and sometimes muscle cramps. Venous thrombosis in the legs and occasionally pulmonary emboli can occur but this is not unique to air travel and can occur whenever people are immobile for prolonged periods, including long bus, train and car journeys. Preventive measures should include general advice to all passengers, including ensuring good hydration, restricting alcohol and coffee intake, regular stretching and mobility exercises.
Respiratory Tract Infections
There is no evidence that re-circulation of air in aircraft cabins increases the risk of transmitting infections since very effective filters are used to remove bacteria and viruses. However sitting in close proximity for long periods next to passengers who are suffering, for example, from common colds or influenza clearly may increase the chances of a passenger becoming infected. This is why airlines discourage passengers from travelling while unwell with infectious conditions.
Skin Parasite Infections
Occasionally head lice and other skin parasites have been passed through contact with aircraft seats when a previous passenger has been infested. This is more likely in countries where these problems are common.
Deep-Vein Thrombosis, Pulmonary Embolus and Air Flights
There have been individual case reports of deep vein thrombosis (DVT) and deaths from pulmonary emboli following airflights but the problem has also been noted following prolonged travel by train or car. Aggravating factors could be pressure from the edge of seats on the back of the leg, dehydration aggravated by caffeine, alcohol and sedation which may encourage immobility.
Suggestions on preventing deep vein thrombosis and pulmonary embolus during air flights:
Be aware predisposing and risk factors
- Predisposing factors for DVT (in addition to the possible effects of prolonged immobility while travelling) are endothelial vascular lesions, hypercoagulabiltity of the blood and thrombophilia (including hereditary forms such as factor V Leiden)
- These factors may specifically include those over 60 years of age, smokers, previous (especially recent) DVT or pulmonary embolus, recent surgery or deep injury, pregnancy or less than 2 months post-partum, malignancy, cardio-respiratory disease, other chronic illnesses, oestrogen medication (contraceptive and hormone replacement), varicose veins. Symptoms can be delayed for several weeks after the flight. Cases of DVT may have an average of 3 factors.
Advice for those at minimal risk (nil or one predisposing factor)
- While further studies are undertaken preliminary advice for those at low risk could be to exercise the legs when possible, maintain hydration and limit alcohol consumption.
Advice for those at low or moderate risk (e.g. 2 or 3 predisposing factors)
- Exercise in the aircraft cabin wherever possible, maintain hydration and limit alcohol consumption, consider using below knee compression stockings. Aspirin is no longer advised as a preventive measure because evidence that it works is lacking and side-effects such as stomach bleeding are significant.
Advice for those at high-risk (e.g. more than 3 predisposing factors)
- Exercise, compression stockings, maintain hydration and limit alcohol consumption. Possibly consider a subcutaneous injections of Minihep (sodium heparin 5000 IU twice daily) or low molecular weight heparin (e.g. dalteparin 2500 daily or enoxaparin 40mg daily) while at risk (so long as anticoagulation is not contra-indicated).
Reference: British Heart Foundation Factfiles. Air Travel and Thromboembolism. Published February 2006
Fear of Flying
In Britain an estimated nine million people suffer anxiety about flying and may miss out on professional and personal opportunities. There is no single personality-type prone to fear of flying and there may be a link with problems at work or home.
Fear may develop from a bad experience - a rough flight, or after a news report of a high jacking or crash. Panic attacks are common (sudden, intense anxiety, sweating and trembling). The sensation is often so frightening that the sufferer may from then on refuse to fly.
Advice for the traveller who is afraid of flying
- Explain that fear of flying is common and emphasize that flying is safer than road or rail travel in most developed countries.
- Try distraction by talking with other passengers, watching in-flight films, eating or reading.
- Tell the cabin crew. Reassurance about strange sounds can help.
- A visit to the doctor prior to travel can provide reassurance about general fitness for air travel.
- Your doctor may advise whether any medication would be helpful. It should be stressed that sedative drugs do not mix well with alcohol.
Cognitive Behaviour Therapy: Recent research has indicated that "cognitive behaviour therapy" can be helpful for more severe cases. The person identifies what they actually fear, and then learns different ways of overcoming it.
Courses and counselling on fear of flying: Aviatours provide courses at Heathrow and Manchester airports (Tel: 01252 793 250).
Air Rage
This term describes psychological or physical violence directed towards cabin staff or other passengers occurring within aircraft. It is of particular concern because of the cramped conditions. There have been instances where aircraft have had to land prematurely to offload disruptive passengers and legal action taken against those involved.
There is often a developing cycle of events, which may include delays, exhaustion due to lack of sleep, excessive use of alcohol sometimes to compensate fear of flying, withdrawal of smoking for heavy smokers, minor irritations due to behaviour of fellow passengers which elsewhere would largely go unnoticed and sometimes anoxia causing irritability in those with pre-existing hypoxic illnesses.
Prevention
Nicotine gum may be useful 'prophylaxis' for heavy smokers. Passengers should avoid excessive alcohol consumption and discourage heavy drinking by their travelling companions. Airlines have the right to refuse to carry those who have previously caused disruption on a flight - warnings may be issued (the equivalent of 'yellow/red card system as used at football matches)
Jet Lag
Changes to Circadian Rhythms
These regulate our sleep patterns, need time to adjust to changes in local time (usually about one day per time zone crossed). Westward travel may be better tolerated than eastward travel but problems occur when travelling in both directions. The effects of jet lag include - sleep disturbance, loss of appetite, nausea and sometimes vomiting, bowel changes (e.g. constipation), general malaise, tiredness and poor concentration.
- A relaxed flight is important.
- Avoid travelling when you are already tired and take rest before departure.
- Remember the actual home to destination travelling time will usually be at least twice the actual time spent in the air since it will include waiting in airports and often unexpected delays.
- Breaking very long journeys halfway with a stopover can be helpful.
- On the flight get maximum sleep.
- Stretch and exercise as much as possible to aid circulation and prevent swollen ankles.
- Drink plenty of water or soft drinks and remember alcohol in spirits and wine and also caffeine cause dehydration (caffeine is present in coffee, tea, chocolate, Coca (and Pepsi) Cola).
- Jet lag is made worse by a hangover!
- Avoid heavy commitments on the first day. Be prepared for tiredness in the evenings and early waking which can last up to 5 or more days.
- Hypnotics (sleeping tablets) such as temazepam have been shown to help sleep and correspondingly alertness during the following day. They do not speed up adjustment the new time zone and therefore may need to be used for several nights.
- Some travellers find taking regular melatonin helpful. It may help the body to adjust its circadian rhythms but its effect is scientifically unproven. It is not readily available in Britain but can be purchased in some countries such as USA and Hong Kong from health food shops or pharmacies.
Airline Restrictions on Flying
Airlines may not allow passengers with the following conditions to fly.
- Pregnancy beyond 36 weeks.
- Neonates during the first few days after birth (longer after premature births).
- Recent or current middle ear infections or sinusitis.
- Unstable psychiatric illness.
- Unstable epilepsy.
- Previously documented air rage or a record of previously causing disruption during flights (some airlines use a 'yellow card' warning system).
- Recent myocardial infarction.
- Moderate/severe heart failure.
- Moderate/severe hypoxic pulmonary disease.
- Recent chest, intracranial or abdominal surgery.
- Recent pnuemothorax.
- The presence of a communicable disease.
Airlines' regulations may vary so if in doubt advice should be sought from the medical department of the airline concerned.
Security in Aircraft
These are examples of items that are not allowed in aircraft cabins:
- Toy or replica guns (plastic or metal)
- Household cutlery
- Knives with blades of any length (including steel nail files)
- Paper knives
- Separate razor blades (disposable razors are normally allowed)
- Tradesmen’s tools
- Darts
- Scissors of any size
- Hypodermic syringes *
- Knitting needles
- Sporting bats (including rackets, cricket bats and golf clubs)
- Billiard, snooker, or pool cues
- Catapults
- Corkscrews with blades attached
* Customers who require the use of hypodermic needles for medical reasons (for example, diabetics and customers with allergies), will be asked for proof of medical need. Please be advised that customers carrying any of the above items (with the exception of hypodermic needles) will be asked to place it in their hold baggage. Customers carrying hand baggage only will be asked to surrender the item for disposal by British Airways
Further advice is available from British Airways: http://www.askbritishairways.com/.
Altitude Sickness on Arrival
Healthy people may travel rapidly to 3500m above sea level but develop symptoms of acute mountain sickness after arrival (headache, nausea, breathing difficulty, mental confusion). Those with respiratory of cardiac problems may experience symptoms on arrival at even lower levels. A few airports are sited above this level, for example, in the Andes and Himalayas, which can mean symptoms, may present after disembarking.
An awareness of the symptoms can be helpful. Plenty of clear fluids should be drunk on the flights since dehydration can worsen symptoms. Rest after arrival with only light activity is recommended because strenuous activity will worsen symptoms. Those with serious pre-existing hypoxic respiratory disease can seek advice prior to departure when an estimate of the degree of hypoxia occurring on exercise may be able to predict whether they will have problems.