Written by: Andra Farcas, MD (PGY-3) Edited by: Phil Jackson, MD (PGY-4) Expert commentary by: William Brady, MD
In-Flight Medical Emergencies
You’re at 35,000 feet reclining in your tiny seat sipping your free ginger ale when suddenly: “Is there a medical professional on board?”
How often can you expect to encounter this?
The incidence of in-flight medical emergencies (IMEs) is difficult to accurately assess, as there is no mandated reporting and most studies gather data from ground medical support, which is not always contacted in flight. Studies estimate 1 in 604 flights will have an IME. Others report anywhere from 24-130 per 1 million passengers; since roughly 4 billion passengers fly annually, this means anywhere from 260-1420 emergencies daily worldwide. Thus, depending on how often you fly, there’s a good chance you’ll be called upon to volunteer.
What will you most commonly see?
The most common reason for an IME is syncope/pre-syncope, which make up about 33-37% of all IMEs. Other common complaints include GI symptoms (15%), respiratory symptoms (10-12%), cardiovascular complaints (7-8%), seizure or post-ictal state (6%), psychiatric (4%), allergic reaction (2%), suspected stroke (2%), diabetes complications (2%), obstetric emergencies (0.7%), and cardiac arrest (0.2-0.3%). About 4% of IMEs require a diversion of the flight.
How is the environment different?
Commercial air travel cabins are pressurized at 5000-8000ft elevation. At this pressure, gas expands by about 30%. Anatomical spaces containing gas, such as sinuses and middle ear, may be affected, as well as non-physiologic gas collections like a pneumothorax or post-operative air collections.
The partial pressure of oxygen is also low at this elevation so even a healthy individual will be mildly hypoxic to 90-93%.
The air is re-circulated, so passengers may be exposed to allergens even if they are many rows away. The re-circulated air is de-humidified so dehydration is also more likely.
Do you have to volunteer? Are you protected if you do?
Ethical obligation aside, do you have a legal obligation to volunteer? In the United States (as well as in Canada, England, and Singapore), physicians have no legal obligation to assist in an IME. In Australia, some European countries, and the Quebec province of Canada, however, they do.
If you do decide to volunteer, you are usually not required to have proof of your credentials in US flights but that may differ based on airline.
In the US, medical professionals who volunteer in IMEs are protected from liability by the Good Samaritan provision of the Aviation Medical Assistance Act except in cases of gross negligence or willful misconduct (such as intoxication, willfully harmful behavior, etc.). Note that if you seek compensation for helping, such as miles, seat upgrade, monetary, etc., you may jeopardize your standing under these immunity laws.
While airlines can get sued for conduct during IMEs, there has only been one reported case in the US of a medical professional being sued for volunteering to assist, and the case was dismissed without hearing.
What equipment and medications do you have?
In the US, all airlines must have the minimum required equipment, which includes basic supplies for assessment, airway/breathing, and intravenous access. Depending on the airline, you may find additional supplies as well.
Internationally, the International Civil Aviation Organization (ICAO), a United Nations agency, regulates international flight safety and recommends that “adequate” medical supplies be on board. While they have recommendations for what those supplies should be, these are non-mandatory and therefore the supplies will vary from country to country and airline to airline.
There are also minimum requirements for on board medications, and additional meds will vary based on airline and internationally.
What support do you have?
Flight attendants in the US are trained in CPR and operating the AED every 2 years. They are familiar with the supplies on board and can be a valuable resource.
If the IME is significant, you can also get assistance from medical ground support. These are medical professionals employed by companies who are contracted by airlines to help with IMEs. They are familiar with the equipment available on the flight, as well as medical resources at nearby airports. The flight crew will tell the pilot, who will contact the med support center and the airline operations center. The crew will then be your communication to ground med support. Since 45% of IMEs are responded to by flight crew alone (with the rest split between doctors and nurses/paramedics), the crew will likely consult ground med support before any interventions (meds, procedures) are taken.
What do you need to know about some specific scenarios?
Cardiac Arrest
Cardiac arrests are rarely the cause of IMEs (0.2-0.3%) but account for 86% of in-flight deaths. The crew should be trained in CPR and operating the AED so your time will be best spent on tasks like IV access and medication administration. Compression-only CPR is a reasonable option, although there are CPR masks on board if there are enough assistants. Terminating a resuscitation effort is tricky in an IME, but some authors suggest it is reasonable after 20-30 minutes of resuscitative effort without return of spontaneous circulation. Only a physician can pronounce death in flight.
Respiratory Compromise
Aircraft are not required to have oximeters. While there are oxygen tanks on US planes, they can only be set to low (2L/min) or high (4L/min) flow and the supply is limited.
COPD exacerbations are not uncommon and there should be bronchodilators on board.
It may be possible to request a descent to a lower altitude to improve oxygenation, although this is complicated given that lower altitude flight uses more fuel.
Pneumothoraces have been reported. If significant, there should be needles on board to perform needle thoracostomy. Descending to a lower altitude may also help in this instance with oxygenation and gas expansion.
Acute Coronary Syndrome
If ACS is suspected, there is aspirin 325mg on board which may be administered if no active bleeding or true allergy. While there is sublingual nitrogen on board, it should be used with caution, as there is no way to rule out an RV infarct.
Altered mental status
Glucometer availability may vary depending on the airline. A solution could be to ask other passengers, though this could compromise sterility and threaten patient privacy.
The seizure threshold may be lowered by in-flight hypoxemia and disturbance in circadian rhythms, and thus a high index of suspicion is advised. Suspected stroke is also one of the common reasons for diversion.
When is diversion reasonable?
The decision to divert a flight for a medical emergency is ultimately made by the captain of the aircraft with recommendations from ground med control and medical volunteers. There are many factors that go into consideration, including cost (anywhere from $20,000 to $725,000 has been reported), fuel amount (planes often take off with more fuel than it would be safe to land with), ability to land at the closest airport, and medical resources available at that airport. One study reported that even when there is a diversion for IME, only 1/3 of patients are actually taken to the hospital by EMS and only 1/3 of those transported are admitted. Most common causes for diversion include cardiac arrest, OB emergencies, cardiac symptoms, suspected stroke or other neuro symptoms, and respiratory symptoms.
Summary
IMEs can be daunting medical encounters to undertake given that you will be faced with limited diagnostic capabilities and a finite arsenal of medications and supplies to treat a wide variety of potentially life-threatening conditions. Regardless, we as emergency physicians are perhaps the most well-equipped medical professionals to handle this strenuous circumstance. If you provide reasonable care that meets your usual standards, then it is extraordinarily unlikely that you will ever be faced with liability. Always, be very cautious when accepting compensation as this may threaten your immunity. Remember that you are never alone and the decision to divert an aircraft will never rest on your shoulders without the support of the ground medical team.
Expert Commentary
Inflight medical emergencies (IME), an unanticipated medical event occurring on a commercial aircraft while in flight, represent a challenge to the volunteer healthcare provider.[1] The challenges are numerous, including the austere environment of the aircraft cabin, the almost complete absence of diagnostic studies, a very limited cache of medical supplies, and the distance from / time to definitive medical care. The aircraft cabin is cramped with little privacy and limited ability to place the patient in a comfortable, supine position; in addition, the ambient noise level is prohibitive to certain physical examination maneuvers, such as auscultation and blood pressure determination.
Diagnostic devices are largely non-existent; the most useful tool is your brain. Medications, basic supplies, and an automatic external defibrillator (AED) are present on all US commercial aircraft and many non-US airlines. While the AED is useful in the happily rare cardiac arrest, other supplies and medications are not particularly useful. In fact, the volunteer healthcare provider should not anticipate the presence of adequate supplies and medications…the aircraft is not an air ambulance or other medical facility. The Table lists required and additional medications and equipment. Please realize that the additional supplies are NOT present on US airlines for a range of reasons, most of which are appropriate and understandable. For example, if diazepam is included in the medical kit, significant risk for the airline is present regarding appropriate storage and use of this potent medication.
The volunteer healthcare provider, at times, may recommend an emergent landing. The volunteer healthcare provider should state his/her case with recommendations in basic, lay terminology. The decision to land the aircraft, however, is made by the captain of the vessel; should the captain disagree with the recommendation to urgently land the aircraft, do not argue. And also realize that during certain flights, there may not be an opportunity to divert and land…for instance, if the flight path is trans-Atlantic.
Lastly, as noted, volunteer healthcare provider on a US aircraft is protected from civil liability, assuming that he/she is not acting negligently in the approach to patient care.
Oddly, as I finished writing this commentary, on a flight to Munich, the announcement “Is there a doctor on board” interrupted my morning coffee. An adult female with a history of epilepsy was having a generalized tonic-clonic seizure. By the time that we (a paramedic and I) responded, she had stopped convulsing; she was post-ictal and gradually awakened over about 15 minutes. Our intervention was placing her in a safety position and maitianing an open airway during her initial posit-ictal period. By the time that we landed, she was alert without complaint. An ambulance met us at the gate; we provided a report on her condition and turned care over to the German medics. Afterwards, I documented the event in my own record and declined the airline’s offer of bonus frequent flyer miles.
References
Nable, J.V., Tupe, C.L., Gehle, B.D., Brady, W.J. In-Flight Medical Emergencies during Commercial Travel. NEJM. 2015;373(10):939-945
William J. Brady, MD
Professor of Emergency Medicine, Medicine, & Nursing
Department of Emergency Medicine
University of Virginia
How To Cite This Post
[Peer-Reviewed, Web Publication] Farcas, A. Jackson, P. (2020, Feb 17). In-Flight Medical Emergencies. [NUEM Blog. Expert Commentary by Brady, W]. Retrieved from http://www.nuemblog.com/blog/in-flight
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References
Aerospace Medical Association Air Transport Medicine Committee. Medical Emergencies: Managing In-flight Medical Events (Guidance materials for health professionals). Aerospace Medical Association. 2016. http://www.asma.org/publications/medical-publications-for-airline-travel/managing-in-flight-medical-events.
Kodama, D., Yanagawa, B., Chung, J., Fryatt, K., Ackery, A.D. “Is there a doctor on board?”: Practical recommendations for managing in-flight medical emergencies. Canadian Medical Association Journal. 2018;26(190):E217-222
Martin-Gill, C., Doyle, T.J., Yealy, D.M. In-Flight Medical Emergencies: A Review. JAMA. 2018;320(24):2580-2590
Nable, J.V., Tupe, C.L., Gehle, B.D., Brady, W.J. In-Flight Medical Emergencies during Commercial Travel. NEJM. 2015;373(10):939-945