Losing consciousness [at 35,000 feet]
Years ago, before I was a physician, I visited my Alma Mater in Baltimore. Took in some of the sights with my (then) girlfriend at the time. We were in the Inner Harbor, kind of a touristy spot. Had just gotten some crabcakes at the Lexington Market, and we were exploring some of the sites. It was about 11am, and we came upon a guy laying down on a bench who was just passed out. Not moving. We walked a little closer to see if he was breathing. Just barely. It was a little surreal. The middle-aged man looked homeless, dirty clothes, unkempt beard. And tourists were just walking around him. Like river water passing around a rock. Half a dozen people walked around his bench as we got closer, nobody paying him any attention at all. I wanted to go over to at least shake him to see if he would wake up. But when I did, there was no response. I felt for a pulse, and by this time one of the workers on the dock came by to see what was going on. Eventually, one of the dock hands gave him a sternal rub, and he aroused a little bit. What else could I have done at the time? In this week’s episode, Dr. Ramani Balu shares his experience in dealing with situations like this–where there are limited resources, and an environment that puts an unusual type of pressure on the body. Take a listen.
This week’s episode is delivered in a clinical case format. I constructed a hypothetical scenario for Dr. Balu and he walks me through it. In my alternate reality, Dr. Balu is on an airplane, traveling at 400 miles per hour at 35,000 feet, and the flight attendant calls out, “Is there a doctor on board?!” Ram, being the gentleman he is, answers the call and rushes to seat 19F. The patient is a middle aged woman who is suddenly unresponsive. What does he do?
ABCs. That’s where Ram starts. Airway. Breathing. Circulation. The 3 tenets of critical care medicine. Does the patient have an intact airway? Nothing obstructing it (no peanuts), no airway edema from a potential anaphylactic reaction, no head/neck trauma with compression of the trachea… Is the patient breathing? Do you hear breath sounds or see a chest rise? Look for signs of oxygenation or hypoxemia–is there cyanosis? Then check for a pulse–I typically go for the carotid in an unconscious patient, but the radial should be fine too. Is the pulse normal and regular? Rapid and faint? And if it’s not there, ACLS and ENLS recommend immediate chest compressions (100-120 per minute, and if you can’t count this in your head, pick a song) with preparation for cardiac defibrillation.
While this is going on, if you happen to be doing CPR or not, it’s a good idea to determine the underlying cause of the loss of consciousness. The most common cause of syncope on an airplane is vasovagal syncope (37% of cases). Other considerations, in no particular order:
- Cardiac arrest
- Pulmonary embolism
Figuring this out on a plane, with limited resources, may not be so simple when you’re panicking at 35,000 feet. Lucky for you, almost 3/4 of flights have at least one medical professional among the passengers. 50% are doctors, 20% of flights have at least one nurse, 4% have a paramedic, and 4% other providers. And not only is there a good chance you’re not alone in the air, the captain can also establish a direct line of communication with an on-call physician from the ground–STAT MD. (We also included an excerpt from this CNN story in the podcast to give you a little more info.
After the airway and pulse have been confirmed, Ram checks the vitals in 19F. The in-flight medical kit comes with a standard stethoscope and blood pressure cuff, but no pulse oximeter. So you’ll have to determine oxygenation based on your good ole fashioned physical exam. If you need to establish an airway, the kit will contain a simple airway device—which you can use if you feel comfortable placing it—along with 3 sizes of a bag-valve mask so you can ventilate someone. The plane will also have dextrose, a 50% intravenous ampule, and some other IV formulations along with a single IV starter kit. (So I hope you’ve brushed up on your peripheral IV skills.)
The hypothetical patient in question eventually arouses as Ram examines her. She is flushed and diaphoretic. His differential diagnosis shifts toward more of a cardiovascular or vasovagal event, and he is able to take a detailed history of the patient. No major cardiac risk factors, no antecedent chest pain. She’s felt a bit dehydrated from that day, and the flight has been a long one. She stood to get some water and that’s when she lost consciousness. To Ram, it felt more like a vasovagal event, which is not uncommon during flights for various reasons. During commercial air travel, the lowered cabin pressure reduces the partial pressure of oxygen from your normal ground-level partial pressure of 95 mmHg to 60 mmHg (at the worst), which corresponds to a 2-3% drop in SpO2. Luckily, most healthy adults tolerate this very well with only minor complaints of headache, fatigue, or lightheadedness. However, for some who have a tenuous oxygen status to begin with, this might tip them over. Additionally, for longer flights, the dry cabin environment may also increase your chances of dehydration, leading to orthostasis and syncope. So, that’s how Ram treated the patient.
When it comes to treatment, are there legal concerns? The simple answer is yes. While you can always call out for help, and recommend flight diversion in emergency scenarios, it will be up to the captain and the on-call physician from the ground who works with the FAA to decide on whether the plane should be rerouted to land emergently or if it is safe to continue the flight to its final destination. As far as potential malpractice is concerned, healthcare professionals are strongly supported by the Aerospace Medical Association as long as they don’t do anything horribly egregious. The Aviation Medical Assistance Act of 1998 protects medically-trained providers in the event of a medical emergency during flight–but only for medical emergencies. To be covered by the AMAA, the provider does not need to be asked for his or her assistance. Nor is the provider liable for any harm done to a patient because of a lack of medical equipment in the standard in-flight medical kit. But the AMAA does have some limitations worth mentioning. And you should remember them if you ever plan to respond to an emergency. The AMAA does NOT cover medical providers for nonemergent medical care that is delivered during commercial flights. If someone develops a nasty rash because you recommended they take ibuprofen for a headache, I know it sounds crazy, but that could be on you. Also providers are not absolved of any gross negligence during their emergent medical care. So if you’ve had a few drinks in flight and they have impaired your judgment, it’s probably not a good idea to offer help. Lastly, providers are not forced to respond to a medical emergency, nor should you feel obligated to help out when it comes to an issue that is beyond your scope of practice.
Who should fly? Because of the risks of hypoxemia and limited available medical resources, certain conditions are contraindicated for commercial air travel. See below:
And with that, I think we’ll call it a day. Remember to travel safely, and to always talk to your doctor about medical concerns and your fitness for air travel. What we talked about in the show today is by no means a recommendation to do or not do anything when it comes to using commercial airliners. Flying should be fun, not frightful.
BrainWaves’ podcasts and online content are intended for medical education and (hopefully) entertainment purposes only. Do not use this as instructions for how to respond to an in-flight medical emergency. Use common sense. Featured image adapted from https://www.flickr.com/photos/jseita/16058572733/ under a CC license.
- Gendreau MA and DeJohn C. Responding to medical events during commercial airline flights. The New England journal of medicine. 2002;346:1067-73.
- Nable JV, Tupe CL, Gehle BD and Brady WJ. In-Flight Medical Emergencies during Commercial Travel. The New England journal of medicine. 2015;373:939-45.
- Silverman D and Gendreau M. Medical issues associated with commercial flights. Lancet. 2009;373:2067-77.