Managing passengers with respiratory disease planning air travel: British Thoracic Society recommendations

Brief needs advice on managing passengers with lung disease air travel is now a common travel model for millions of people, with a British airline shipping 33 million passengers a year.
It is estimated that more than 1 billion passengers travel by plane every year around the world, and in most cases there is no danger.
Despite the uncertainty of the future of the airline industry, air travel still seems likely to provide convenient transportation for many people.
Therefore, the number of passengers may increase further in the long run.
With the age of the Western population, the age of air passengers may also increase, and the tendency to medical damage will increase.
It is estimated that 25 years ago, 5% of commercial airline passengers were outpatient patients with some diseases, including chronic lung disease. 1oas_tag.
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There is no way to quantify risk.
Medical problems in flight
However, a North American service company is in-through a radio link-
In 2000, a flight medical emergency recorded 8500 calls, of which 11% were from the respiratory system.
Therefore, doctors should be aware of the potential impact of the flight environment on passengers with lung disease.
1 million residents of Denver, Colorado live 5280 (1609 m) and the coach crossing the Alpine pass reaches 10 000 (3048 m), indicating that moderate hypoxia is generally not at risk.
Nevertheless, raising awareness of the risks of air travel will enable physicians to encourage patients to fly as safely as possible and to improve the safety of fellow air passengers.
The crew undergo regular medical examinations, but the passengers do not.
For potential passengers with lung disease, it is obviously valuable that their doctors have suggestions to assess whether a patient is fit for flight.
A recent national survey of respiratory physicians shows that many people will welcome their advice.
Available sources of information include UK and Europe, 4-6 North America, 7 and Canada 8 guidelines for chronic lung disease, textbooks for Aviation Medicine, and 9 additional materials from the Journal of Aviation, space and environment Medicine10-12 and other publications on air travel.
However, doctors may not always have easy access to these references, and not all of them provide consistent, practical or comprehensive coverage.
In particular, there are differences between guidelines in Europe and North America, uncertainties in the assessment methods, and other respiratory causes that do not take into account hypoxia, such as lung biopsy.
In order to meet the needs of consistent, practical and comprehensive advice, the British chest Association (BTS) committee on standards of care has set up a working group to develop national proposals for managing air travel for patients with lung diseases.
There is not enough evidence to develop formal guidelines.
The following suggestions are from a literature review designed to provide practical advice for respiratory physicians.
They are for commercial flights only and do not include emergency air medical evacuation.
The purpose of the recommendation is to improve the safety of passengers with lung disease by plane and reduce the number of passengers
Flight medical accidents caused by respiratory diseases.
In order to improve the recognition of health care professionals that patients with respiratory diseases may need clinical evaluation and advice before traveling in the air.
Provide an authoritative and up-to-date literature review of existing evidence.
Provide consistent, practical and comprehensive advice to healthcare professionals managing such patients.
Develop key research issues to lead to further investigations.
This should result in a strengthened, high-quality evidence base from which clearer evidence can be obtained
Guidelines can be developed.
Promote the development of methods to monitor the scale of problems.
The working group identified the objectives and objectives of the proposal.
The members of the working group conducted an independent literature search, resulting in a draft document summarizing the current evidence and containing information on (1) the flight environment, (2) (3) clinical assessment exposed to altitude, (4) respiratory diseases that may be at risk for potential air travelers, (month) oxygen supplements.
The working group reviewed and redrafted the document.
It is then distributed to the reviewers listed in the Appendix care standards committee and Appendix 1 and then made available to the BTS members in the member-specific section of the BTS website.
After discussion and further review by the BTS care standards committee, a final draft with feedback was prepared.
The strength of the evidence was agreed and it was recommended to be graded according to the Inter-University of Scotland Guidelines Network (SIGN) standard shown in Appendix 2.
Summary of key points and suggestions for AHCPR grading flight environments and impacts of modern aircraft are pressurized to cabin heights up to 2438 m (8000 m), although this maximum may be
The cabin height of the Concorde aircraft is about 1829 (6000) lower.
At 2438 m (8000 m), the fractional pressure of oxygen will drop to the equivalent of breathing 15.
1% oxygen at sea level.
Among healthy passengers, arterial oxygen tension (pa02) of 2438 (8000) is affected by age and minute ventilation but is reduced to 7. 0–8.
5 kPa (53-64mm Hg, sp02 85-91% ).
Therefore, there is concern that altitude exposure may aggravate the lack of oxygen in patients with lung disease, and it seems reasonable for those who lack oxygen at sea level to be particularly careful.
Physiological compensation for acute hypoxia at rest is mild to moderate over-ventilation (reducing arterial CO 2 tension (PaCO 2) relieving over-ventilation) and moderate over-speed. Pre-
The following groups should be assessed for adult flight assessment: severe chronic pulmonary or asthma;
[B] severe restricted diseases (including chest wall and respiratory muscle diseases), especially those with hypoxia and/or high carbon dioxide;
[C] Patients with cystic fibrosis;
[C] a history of air travel intolerance with respiratory symptoms (breathing difficulties, chest pain, confusion or fainting; [C]co-
Incidence of other diseases aggravated by hypoxia (cardiovascular disease, coronary artery disease, heart failure;
[C] Tuberculosis;
[C] acute respiratory disease within 6 weeks of discharge from hospital;
[C] The recent occurrence of the chest;
[B] the risk of venous thrombosis or the previous risk; [B]pre-
Existing requirements for oxygen or ventilator support.
[C] It is recommended that the following assessments be conducted: in particular, the history and examination of heart and lung disease, difficulty breathing, and previous flight experience;
[C] lung capacity test (non-
Patients with tuberculosis only );
[C] spo 2 was measured with pulse oximeter.
After sufficient delay, the reading should be taken from warm ears or fingers so that the blood oxygen meter shows a stable reading.
If high CO 2 is known or suspected, blood gas tension is preferred.
[C] in those who were screened out with a static sea level oximeter with additional risk factors between 92% and 95% (table 1,293), it is recommended to conduct a hypoxia challenge test 293 ).
[C] Note that the following groups should not fly: patients with infectious tuberculosis are not allowed to travel by public air transport until they have not flowninfectious.
In effective TB treatment, three Smear negative sputum tests performed by a person on different days indicated that the probability of transmission was extremely low, and the negative culture results actually ruled out the possibility of transmission;
[B] those who have now closed their chests should avoid commercial air travel.
[C] patients who have undergone major chest surgery are better off delaying the flight for 6 weeks after a simple procedure.
[C] The patient should fly only if necessary, and a formal medical assessment is required before departure.
In fact, some airlines are prepared to receive patients within 2 weeks after a big chest surgery.
The relative risk of both approaches is not clear, but either approach requires careful medical assessment in advance.
Lung cancer itself is not a taboo in flight.
However, the associated respiratory diseases should be considered on their own.
[C] Additional precautions for all passengers: prior to flight and during flight, especially those with the risk of blocking sleep apunoah and venous thrombosis, excessive drinking should be avoided;
[C] individuals who do not receive oxygen during the flight should keep moving;
[C] The exercise of not Supplementing oxygen may aggravate the lack of oxygen;
For the most compromised, it may be prudent to use oxygen while the plane is on the way and let the flight attendants know how long they expect to leave their seats;
[C] preventive measures should be initiated at the risk of thrombosis, as detailed in the summary below;
[B] prevention and mitigation of inhalation should be carried in the patient\'s hand luggage;
[C] A portable nebulizer may be used at the discretion of the crew, but there is sufficient evidence that the spacers are as effective as nebulizers in the treatment of asthma;
[A] The patient shall verify with the local or hospital pharmacist whether there is any medication that will be adversely affected by the extreme temperature of the baggage compartment;
[C] apnoea patients with sleep blocking on long flights may require continuous gas channel positive pressure (pap) machines powered by dry batteries, but they must be turned off before landing;
[C] patients on ventilator-dependent shall inform the airline of their requirements at the time of booking and ask the doctor\'s letter to outline medical diagnosis, necessary equipment, recent blood gas results, and ventilator settings.
A medical staff is likely to be needed.
Must be arranged to pass the air station before and after the flight.
[C] air transport logistics of oxygen: Supplement-
Flying oxygen is usually opened at a speed of 2 liters/minute and should be given by a nasal catheter. In-
Before the aircraft is at cruising altitude, flying oxygen does not need to be turned on and can be turned off at the beginning of the descent.
For patients with oxygen at sea level, the rate should only increase when cruising altitude.
[B] in complex cases, patients can be tested in a low-pressure chamber.
The center is listed in Appendix 3. Even with in-
Flying oxygen is not safe to travel.
Air travel is almost always possible with proper medical support, but in individual cases logistics and economic costs may outweigh the benefits. Pre-
The child flight assessment is prudent to wait 1 week after birth before allowing the baby to fly to ensure the baby\'s health.
[C] if the baby has any neonatal respiratory problems, the proposed journey should be discussed with the pediatrician and the hypoxia challenge test should be considered.
[B] oxygen dependent children, including ex-children
Premature infants with chronic lung disease (lung dysplasia), if flying is essential, the oxygen demand should be titration in the body box of [B, placed in a body box in the company of a parent or caregiver as shown below and monitored spo 2.
Then dilute the air in the body box to 15% oxygen with nitrogen.
The flow of oxygen was measured by the nasal catheter, and any drop in spo 2 could be restored to the original value.
This oxygen flow should then be provided during flight.
As mentioned above, a disease-specific recommendation assessment is recommended.
Prevention and Mitigation of inhalation should be carried in hand luggage.
The crew can use the portable nebulizer at their own discretion.
They may be connected to some but not all airline aircraft power supply.
Some airlines can do it for in-
At the time of booking, the use of the flight and the patient should check with the carrier.
The capsule is as effective as the nebulizer.
As mentioned above, COPDAssessment is recommended.
Passengers should take Nonsmoking flight.
Prevention and Mitigation of inhalation should be carried in hand luggage.
The crew can use the portable nebulizer at their own discretion.
They may be connected to some but not all airline aircraft power supply.
Some airlines can do it for in-
At the time of booking, the use of the flight and the patient should check with the carrier.
The capsule is as effective as the nebulizer.
In-
Flying oxygen should receive oxygen when visiting a high altitude destination (see Appendix 4 ).
Many airports offer wheelchairs to and from aircraft.
As mentioned above, it is recommended that a cystic fiber assessment be performed by a cystic fiber degeneration physician.
To allow for delays and stopovers, the drug should be separated between hand luggage and hand luggage.
The portable nebulizer can be used at the discretion of the crew and can be connected to some but not all aircraft power supplies.
Some airlines can do it for in-
At the time of booking, the use of the flight and the patient should check with the carrier.
The capsule is as effective as the nebulizer.
During the stopover, passengers should have physical therapy. In-
Atomization antibiotics and DNase are not required.
Passengers should check with the pharmacist if there is any medication that will be adversely affected by the extreme temperature in the baggage compartment.
Many airports offer wheelchairs to and from aircraft.
As mentioned above, infection assessment is recommended.
People who are known to have infectious tuberculosis should refuse to board the plane.
Patients with infectious tuberculosis are not allowed to travel by public air transportinfectious.
WHO guidelines point out that in effective TB treatment, three Smear negative sputum tests performed by a person on different days indicate that the probability of transmission is extremely low, and the negative sputum culture results actually exclude transmission
This is probably over. cautious.
While this remains a policy for HIV-positive patients, in practice, HIV-negative patients who have completed 2 weeks of effective TB treatment are generally considered No. infectious.
As mentioned above, it is recommended to conduct a fiber tissue check.
As mentioned above, it is recommended to evaluate neuromuscular diseases and spinal lateral processes.
Ventilator dependent patients for all patients: Airlines must be consulted before booking.
A doctor\'s letter is required outlining medical diagnosis, necessary equipment, recent blood gas results, and ventilator settings.
It should indicate that the ventilator must travel in the cabin as an additional hand luggage.
It\'s best to avoid long flights.
It is recommended to use the dual 110/240 v function so that the ventilator is compatible with the voltage of the intended destination.
Dry battery pack is critical for the back
It is carried out by air terminal before and after flight.
Patients with permanent (24 hours) ventilation: patients who rely on the ventilator need medical escort.
If arranged in advance, the power supply can be provided on the flight.
Wet acid batteries are prohibited.
In the event of a power failure, medical escorts must have the ability to replace pipes, operate suction devices and ambu bags that provide emergency ventilation to patients.
A spare air pipe and a battery-driven suction device must be used.
Due to the decrease in air pressure at high altitude, patients with tracheal surgery should replace the air in the tube sleeve with equal volume of salt water before boarding.
As mentioned above, it is recommended to conduct a blocking sleep apnoea (OSA) assessment.
Airlines must be consulted before booking.
A doctor\'s letter is required outlining medical diagnosis and necessary equipment.
It should indicate that the ventilator should travel in the cabin as an additional hand luggage.
It\'s best to avoid long flights.
It is recommended to use the dual 110/240 V voltage function so that the ventilator is compatible with the voltage of the intended destination.
A dry battery powered ventilator can be used during flight, but must be turned off before landing.
Patients should avoid drinking alcohol before and during flight.
Patients with mild snoring and excessive sleep are unlikely to need a ventilator during flight.
Patients who intend to sleep significantly less saturated during flight should consider using their ventilator.
Patients who are significantly less saturated during sleep when traveling to high altitude destinations should use a ventilator (see Appendix 4 ).
Patients with pneumonia who have previously been closed should not travel on commercial flights.
Patients can fly 6 weeks after a clear surgical intervention and treatment.
Careful medical assessment is required in advance.
Patients without surgery must have a chest X-ray to confirm the resolution and have passed at least 6 weeks after the resolution before travel.
Although it is unlikely to recur during flight, the consequences of high altitude may be significant due to the lack of timely medical care.
This is especially true for those with additional cooperation
Existing lung disease
Passengers may want to consider other modes of transport within 1 year of their first event.
Venous thrombosis disease (VTE) all passengers should avoid excessive alcohol and caffeine-containing drinks, preferably to maintain activity or exercise the legs during flight.
Passengers with a slight increase in the risk of VTE include passengers over the age of 40, obese passengers or a wide range of patients with varicose veins, patients with multi-red blood cell disease, and passengers who have undergone minor surgery within the last 72 hours.
In addition to the above precautions, they should avoid alcoholic and caffeine-containing drinks, which require only a short sleep time and avoid taking sleeping pills unless they reach a normal sleep state.
Support tights or non-tights may be recommended by doctors
Stretch stockings.
Passengers with moderate increase in risk of VTE include passengers with a family history of VTE, recent myocardial infarction, pregnancy or estrogen therapy (including hormone replacement therapy and some oral contraceptives), and patients who deliver within 2 weeks after delivery, as well as patients with lower limb paralysis, recent lower limb trauma or recent surgery.
In addition to the above notes, the doctor may wish to recommend the pre-
Fly aspirin and graduated compression stockings.
VTE high-risk passengers include passengers who previously had VTE, passengers who were prone to suppository, passengers who have experienced thromb in the past 6 weeks, passengers with a history of stroke, or patients with currently known malignant tumors.
If flight cannot be avoided or delayed, as an alternative to low-dose aspirin, the international normalized ratio (INR) is recommended) the low molecular weight heparin or the formal anticoagulant may be cautious within the range of treatment before departure (2-3 ).
Depending on the length of time spent abroad, passengers may need to maintain an anti-coagulation status before returning.
Chest surgery assessment is recommended as mentioned above.
After simple chest surgery, air travel should be delayed for at least 2 weeks and it is recommended to confirm the resolution of any chest or collected air by chest angiography.
Careful medical assessment is required before traveling.
Travel logistics to provide oxygen to all patients when a patient makes a reservation with an airline, the demand for oxygen should be disclosed.
The airline Medical Department will issue the MEDIF form (see Appendix 5) or its own medical form.
This requires completion by patients and general practitioners or hospital specialists and requires information on the patient\'s condition and oxygen needs.
The airline\'s medical officer then assessed the patient\'s needs.
The need for oxygen on the ground and when changing flights must be considered.
If the patient wishes to use the humidifying equipment, consult the airline in advance.
The airline does not provide oxygen for use at the airport.
Due to the danger of an explosion, some airports have restricted the use of oxygen at the airport. In-
Flight oxygen flow is usually limited to 2 liters/minute or 4 liters/minute.
Patients cannot use their own cylinders or concentrator, but if they are empty, they can carry these items as luggage with them.
They should check with the airline first.
There may be a charge for this service, in addition to an internal chargeflight oxygen.
Patients are advised to check the fees with several airlines before booking, as there is a big difference in fees and services.
For patients who are completely oxygen dependent, special arrangements must be made with the airline and airport authorities.
It is possible to ship to the plane by ambulance, and some airports have a specially designated medical unit.
Patients should have a copy of all their commonly used medicines, medical forms, and be accompanied.
It is best to direct.
If the transfer is inevitable, oxygen must be arranged separately on the ground during the stopover.
The main oxygen distributors have their own international distribution network and can supply oxygen at their intended destination if active in these areas.
Patients who usually use long-term oxygen therapy (LTOT) should ensure that they have LTOT throughout their stay.
In case of difficulties, major lung charities in the UK may offer advice.
Attention should be drawn to the need for prior arrangements for return and return trips.
Look here: check the preliminary results of inlineView popupTable Assembly View month: the results of the tolerance test for inlineView popupTable monthly hypoxia (monthly score of 15% Fio2) and AHCPR test grade (Appendix of month number) the search engines used are Medline (English) 1966-99 and the Cochrane Library database.
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A summary of the advice given to general practitioners is provided on the Thorax website (www. thoraxjnl.
Com) and the website of the British chest Society (www. brit-thoracic. org. uk).
Background literature review the flight environment in order to understand how the flight environment affects physiology and occasional pathology, it is useful to consider the physical properties of the atmosphere and the changes that occur when rising to high altitude.
The atmosphere consists of several concentric \"shells\" around the Earth.
The innermost shell is the atmosphere, extending from the ground to 9144 m (30 000) at the poles and 18 288 m (60 000) at the equator ).
Regular aircraft operate in this area.
It is characterized by a relatively constant drop in temperature with an increase in altitude and a drop rate of 1.
Up 305 (1000 ).
The air is compressed by gravity.
As a result, the atmospheric pressure at sea level is the largest and is decreasing in numbers with the rise (Figure 1 ).
Small changes in the low altitude, so the same changes in the high altitude cause greater pressure changes.
The table in Appendix 6 shows a conversion chart from foot to meter.
Download the relationship between atmospheric pressure (mm Hg) and height (feet) in Figure 1 of figure open in the new tabDownload powerpoint.
The atmosphere contains 21% oxygen, 78% nitrogen and 1% other gases (including ar and carbon dioxide, which are 0. 03%).
With the decrease of total pressure at the time of rise, the decrease of oxygen pressure will lead to low pressure hypoxia, not a change in the percentage in the air.
Changes in pressure and temperature have other physical effects described by the law of gas.
Boyle\'s law predicts that the increase in gas volume will be inversely proportional as the pressure rises.
This affects the body parts where the gas is captured, including the middle, inner ear, sinus, and intestines.
Although the gas that freely communicates with the surrounding air is easily balanced, the same effect occurs in the lungs.
If any, it is unlikely that the gas trapped in a lung bubble or a closed chest will balance as quickly as it used.
The volume of the gas is also related to temperature, but the temperature of the gas captured in the body remains unchanged at 37 °c.
The cabin pressure of modern aircraft ensures that the effective height of passenger exposure is much lower than the effective height of aircraft flight.
Commercial aircraft are not pressurized at sea level, but at a relatively mild intermediate cabin height.
This allows the aircraft to fly at a higher altitude, which is fuel-efficient for the jet engine, and is more comfortable because it avoids a lot of turbulence.
Therefore, when the aircraft is flying at 11 2438 m (38 000 ft), the height of the cabin can be close to 8000 m (582 ).
As a result, there is a differential pressure on the cabin wall, usually 9 pounds lbs (psi) per square inch ).
International aviation regulation 16 stipulates that the cabin pressure shall not exceed 2438 (8000) at the maximum cruising height of the aircraft ).
This may be exceeded in an emergency.
A study of In-
The cabin height of 204 regular commercial aircraft flights shows a significant change in cabin height.
17 if the cabin pressurizing system fails at high altitude, all passengers need to replenish oxygen to prevent an unacceptable degree of hypoxia.
As a result, commercial aircraft are equipped with emergency oxygen systems for passengers to demonstrate before each flight in accordance with civil aviation regulations.
However, some passengers with impaired breathing function, even at normal cabin height, may be unusually vulnerable to rising.
It is these issues that are discussed here.
These proposals apply only to large commercial aircraft.
They do not apply to small private or stress-free aircraft operating under general aviation regulations.
The physiological effects of exposure to still breathing air at 2438 m (8000) and 1524 m (5000) are equivalent to breathing 15. 1% and 17.
1% oxygen at sea level.
In healthy subjects exposed to these conditions, their pa02 is affected by age and minute ventilation, but the pa02 may drop to 7. 0–8.
5 kPa (53-64mm Hg, sp02 85-91% ).
Healthy passengers, however, generally do not have symptoms.
Appendix 7 shows the conversion data to baipa and mm Hg. Clinical pre-
There are three procedures in which flight assessment is currently used to assess whether a patient is suitable for flight: (1) a 50-meter walk, (2) a prediction of hypoxia from the equation, and (3) an hypoxia challenge test
50 m walking ability to walk 50 m without pain, traditionally favored by airline medical department due to its simplicity, but it is usually the only subject of inquiry, unverified
There is no evidence to confirm the test.
Although this seems to be a rough assessment, the ability to increase the volume of minutes of ventilation and cardiac discharge under exercise load is a good test of heart and lung reserves.
This is also a common method that can simulate the extra hypoxia pressure that patients will encounter during the flight at rest.
Respiratory physicians have the value of a walking test in other cases, including a 6 to 12 minute walk and a shuttle walk test.
21-23 this test is increasingly being used as part of the assessment of patients with lung volume reduction surgery and lung transplant.
The walking test used should be the test used in the laboratory in which the assessment was conducted.
Failure to complete the task (in terms of distance or time) or moderate to severe respiratory distress (recorded with a visual analog scale) will remind doctors and patients that they may need to be hospitalizedflight oxygen.
For people with arthritis of the lower limbs or weak nerves, the walking test is obviously not suitable.
Use one of several equations to predict carbon dioxide or carbon dioxide measured at sea level (see Appendix 8 ).
24-28 these equations are almost entirely derived from patients with chronic lung obstruction who measure carbon dioxide in low-pressure chambers, or before and during exposure to simulated elevations, breathe 15% of the oxygen from the reservoir bag.
Measuring the amount of forced breath (v1) within 1 second can improve the accuracy of the predicted value.
A weakness of 25,26 is that the 90% confidence limit is ± 1 kPa (± 2-4% spo ).
However, these predictions are reliable enough to establish up and down thresholds for \"no input\"
Flying Oxygen \"(spo> 95%) or\" in-
(Spo 9 at rest.
Therefore, 3 kPa or spo> 94% does not rule out highly severe hypoxia in patients with severe chronic lung obstruction.
A slight movement, equivalent to a slow walk along the aisle of the plane, may aggravate the lack of oxygen.
The risk of re-emergence of large bubbles is discussed separately, but it should be noted here that patients with chronic obstruction of lung with large bubbles theoretically increased due to volume expansion under reduced cabin pressure.
Volume of non-medium gas
Communication bulla will increase by 30% when rising from sea level to 2438 (8000.
One case reported a fatal air embolism in a patient with a giant pulmonary airway cyst.
46 however, there is no data to be sure as to what the maximum volume of bulla should be or air embolism before bulla reaches an unacceptable level of risk of rupture
The UK\'s recent guidelines on oxygen prescriptions 47 cited evidence from two studies 24, 48, which suggest that the best predictor of pa02 in high altitude areas is the former
Fly on the ground.
In a study, the authors measured pa02 and Paco2 in 13 patients with chronic lung obstruction at 1650 and 2250.
Although pa02 decreased from 9, no symptoms caused by hypoxia were recorded. 1 kPa (68.
2mm Hg) at sea level to 6.
6 hundred PA (51mm Hg) at 1650 m and 6. 0 kPa (44.
7mm Hg) at 2250 m.
Carbon dioxide measured at sea level a few weeks ago was not related to carbon dioxide measured at high altitude, but measured carbon dioxide within 2 hours of flight time was not relevant.
In the second study, 18 retired soldiers with severe chronic lung obstruction were exposed to altitude of 2438 (8000) above sea level in the low-pressure chamber.
Pa02 dropped from 9. 6 kPa to 6.
After 45 minutes in a stable state, 3 hundred PA.
The authors describe a predictive equation and recommend the use of pre-
Fly fe1 to limit the change of pa02 results at altitude.
In a review of acute responses to altitude in patients with heart and lung, Gong et al suggested in-
Oxygen before flight
Flight pa02 for breathing 15% oxygen at sea level