Medical Conditions And Flying ∣ Avoid In-flight Emergencies

I’m sure you, the patient, hate the idea of an in-flight medical emergency as much as doctors do. 

Most doctors dread the “Is there a doctor on board?” call and feel uncomfortable about being put on the spot. We are only human, after all.

• The emergency might be out of our scope of practice. Patients have the impression that a doctor knows everything. The last time I delivered a baby was 20 years ago. Although I am trained in CPR and AED use, I am not an emergency specialist.
• The environment is unfavorable. It is noisy and cramped, and there is no privacy. The equipment and medication we need might not be available. I have a personal example. Recently, my partner had a severe allergic skin reaction on board a 10-hour international flight. Staff had not replaced the antihistamine tablets in both medical kits. Luckily, it was not a life-threatening allergy.
• Backup might not be accessible.
• Doctors are off duty, not expecting to work, and might have had alcohol or taken a sleeping tablet.

It’s not ideal; you don’t want to receive emergency care at 36,000 feet.

So, how can patients help doctors to avoid this call to action? 

Read this post on medical conditions and flying and reduce the chances of this happening to you.

Medical conditions and flying

I will cover the two topics.

• General reasons why flying might affect your body. Try to make sure you know how to keep yourself healthy on board. 
• Specific health conditions that need special attention. Understand the relationship between your existing medical conditions and flying.

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General reasons why flying might affect your body.

1. Cabin pressure

Cabin pressure is kept relatively low. It is the same as 1,800 to 2,500 meters (6,000 to 8,000 feet). Most healthy people cope with this altitude, but it has subtle changes that might affect some patients.

∗ Drop in O₂

Patients with heart failure and lung disease might battle. ² If you are short of breath or your oxygen level is relatively low at rest, you might have an issue if you fly. ^1,3,4

∗ Gas expansion

Air trapped in a body cavity expands and can increase up to 30%. ² 

Site Affected	Symptoms	How To Avoid Problems
Sinuses & middle ears	Facial pain, headache or earache	During take-off and landing: -Swallow (particularly while holding the nose closed) frequently -Yawn -Spray decongestants into the nose 30 minutes before -Chew gum or suck on hard candies (bottle or breastfeed or pacifier for infants)
Bowel	Flatulence, bloating, or abdominal pain.	-Avoid eating: Beans, lentils, cabbage, broccoli, cauliflower, bok choy, brussels sprouts, bran, peanuts, or anything that makes you gassy -Avoid fizzy drinks or beer -Wear loose trousers with stretchy waists

There are situations when you should not fly because of the gas expansion. ^1,2 

Reasons not to fly because of the cabin pressure
-Sinus or middle ear infections
-Within two weeks after significant surgery 1,2
-Within 7 to 10 days after diverticulitis 1
-Within 7 to 10 days after a bowel obstruction 1
-Within 12 hours after diving once per day without decompression 1
-Within 24 hours for divers participating in several dives per day, or a dive requiring decompression 1

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2. Low cabin humidity

Cabin humidity is about 10 to 20%, a third of our physiological comfort zone. 

∗ Dry body surfaces

Everything exposed to air will dry out and cause medical problems. This includes skin, eyes, throat, and lungs. ⁴ 

• Nose bleeds
• Sore throat
• Coughing
• Asthma attack

Use eye drops, saline nasal spray, lip balm, and moisturizing skin cream to keep yourself comfortable.

∗ Dehydration

You also lose fluid in cells and blood volume.

An estimated 250 ml/hour, according to Bob Bacheler, managing director at Flying Angels, in a CNN article.

That means up to 2 liters during an 8-hour flight. This dehydration can result in serious consequences.

• Light-headedness, fainting, or collapse
• Headaches
• Confusion

Try to drink 250 ml of water /hour to maintain balance.

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3. Immobility

Stuck in the plane, we have nowhere to go and not much to do for hours. It might be worse if you’re sitting in a middle or window seat.

This can cause the most life-threatening medical condition of all.

∗ Deep vein thrombosis (DVT)

Even healthy people are at risk of clots on a flight longer than 8 hours. Four times higher than their home baseline. Why is this?

Two factors contribute. ¹ 

• Dehydration
• Immobility

Most of us know how difficult it is to get your shoes back on after a long flight.

Reducing your risk of clotting while flying. ¹

• Drink 250 ml of water per hour
• Avoid alcohol
• Avoid caffeine
• Get an aisle seat
• Get up and walk every 1 to 2 hours
• Avoid crossing your legs
• Wear loose trousers with stretch waists
• Do simple calf exercises while seated 
• Wear compression stockings

I highly recommend compression stockings as they decrease the risk of swelling and blood clots. It is essential to have them fitted by a professional to ensure the stockings work; if they are too loose, they won’t work, and if they are too tight, they can be uncomfortable and restrict blood flow.

Unfortunately, business-class versus economy-class travel does not reduce venous thromboembolism incidence. ¹

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Specific medical conditions that need attention when flying ⁵

Always ensure you take enough chronic medication and medical devices for your trip. Keep it with you in your carry-on luggage.

If you are going away for a long time or taking a flight longer than 8 hours, consider visiting your doctor for a checkup.

1. Heart disease

2. Lung conditions

∗ Asthma

Carry a rescue inhaler, and consider taking emergency cortisone with you.

∗ COPD/Emphysema

If your home baseline oxygen saturation is low, it will drop more on the flight. Consult your doctor before you leave if you might be at risk.

∗ Recent or history of lung collapse

Always ask your specialist for an action plan and be prepared.

3. Diabetes

Always carry your glucometer and sweets in case of an emergency sugar low.

Contact the airline ahead of time to enquire about their medical device policies. Check your transit airport rules, as you must clear injectables and lancets at security.

4. Pregnancy

Always check with your doctor if it is safe for you to fly. Tell them where you are traveling to and how long the flights are. 

Check with the airline before you book tickets, as policies differ.

“For instance, an airline may require that a woman in her 9th month of pregnancy who wants to fly must have a doctor’s written approval letter dated within 72 hours of departure that states her expected delivery date.” ⁵

Bear in mind that the DVT risk increases during pregnancy. Your Ob-Gyn will advise you on your situation and how to minimize risk.

References

1. Silverman, D., & Gendreau, M. (2009). Medical issues associated with commercial flights. Lancet (London, England), 373(9680), 2067–2077. https://doi.org/10.1016/S0140-6736(09)60209-9; https://www.thelancet.com/journals/lancet/article/PIIS0140673609602099/fulltext
2. Nable, J. V., Tupe, C. L., Gehle, B. D., & Brady, W. J. (2017). Is there a doctor on board? In-flight medical emergencies. Cleveland Clinic journal of medicine, 84(6), 457–462. https://doi.org/10.3949/ccjm.84a.16072
3. Chandra, A., & Conry, S. (2013). In-flight Medical Emergencies. Western Journal of Emergency Medicine, 14(5), 499-504. https://doi.org/10.5811/westjem.2013.4.16052
4. Ho, S. F., Thirumoorthy, T., & Lui Ng, B. B. (2016). What to do during inflight medical emergencies? Practice pointers from a medical ethicist and an aviation medicine specialist. Singapore Medical Journal, 58(1), 14-17. https://doi.org/10.11622/smedj.2016145
5. Sanford, C., & Lindley, A. (2022b, December 1). Specific medical conditions and travel – special subjects. MSD Manual Consumer Version. https://www.msdmanuals.com/home/special-subjects/travel-and-health/specific-medical-conditions-and-travel 
6. Sanford, C., & Lindley, A. (2022a, December 1). Problems in transit – special subjects. MSD Manual Consumer Version. https://www.msdmanuals.com/home/special-subjects/travel-and-health/problems-in-transit 
7. Zubac, D., Stella, A. B., & Morrison, S. A. (2020). Up in the Air: Evidence of Dehydration Risk and Long-Haul Flight on Athletic Performance. Nutrients, 12(9). https://doi.org/10.3390/nu12092574