Camels and Airplanes Part Two

With the understanding from last month of how our inner ears, eyes, and brain gang up on us to cause motion sickness, it’s time to answer the questions of who gets motion sickness, what you can do about it in the air, and some things to prevent it. 

Whether you were riding a camel thousands of years ago or you’re up in space today, motion sickness is another one of those sensory illusions we’ve been talking about for the last few months. It’s simply a discrepancy between what you see and what you feel when the information you get from your eyes and the information from the vestibular organs of your inner ears don’t match up. As we all know, nausea is the primary symptom and it’s no wonder that the word “nausea” comes from the Greek word naus, meaning “ship.”

The answer to the first question is that everyone gets motion sickness, some very easily while others are more fortunate and almost never feel sick. Most studies of pilots show that airsickness occurs, at least occasionally, in about 25-30% of airline pilots. Motion sickness is even more common when using a flight simulator, and up to 70 percent of pilots can be affected. The military has studied this extensively and the FAA even has a name for it, “simulator sickness.” It’s so common that the FAA has specific recommendations discouraging driving and flying within 12 hours of sim sessions. Surprisingly, the most experienced pilots are the most susceptible to motion sickness in a simulator. It’s probably because they are more familiar with what the sight pictures of flight should look like, and when the simulator motion doesn’t agree, the difference between visual and vestibular senses is more egregious. Commonly, but not always, the frequency of motion sickness symptoms diminishes as flight time and exposure to motion increases, since your brain can get “used” to the sensations of the eye/ear discrepancy.

Kids usually get motion sickness fairly frequently starting at about two, peaking in adolescence, and generally improving with passing years. Women are more susceptible than men due to estrogen, which has been shown to contribute to motion sickness. Monthly menstrual cycles worsen motion sickness risk and frequency, as do birth control pills that contain estrogen, and estrogen supplements that treat the symptoms of menopause. Athletes tend to be more susceptible probably because people who are fit have highly tuned proprioceptive senses (check back last month for details) and are more likely to be affected by eye/ear sensory conflicts. Other factors that make symptoms more frequent and severe are things like anxiety and stress, large meals (especially ones high in salt, protein, or dairy products), alcohol, smoking, and bad odors. Unfortunately, once you get motion sickness you’re much more likely to get it again. It’s a little bit like a premonition; when you start to get that uncomfortable sensation your stress levels go up knowing what’s coming next, then there’s no stopping it. Similarly, anxiety about getting motion sickness brings on just the symptoms that you dread so much and is related to nausea brought on by the release of stress hormones we detailed last month. Motion sickness has also been shown to be “contagious” due to the same suggestibility and anxiety among a group of travelers.

The key to treating airsickness when it strikes is to remember the details we covered last month on how you get it in the first place. The hardest thing to do is to relax, but it’s important since it will reduce those stress hormones of anxiety that are adding to the symptoms you’re already having. Take a few slow, deep breaths and try to deal with any anxiety about the flight or other conditions by concentrating on resolving problems. Additionally, you have to try to reverse the sensory conflict process by getting your eyes and inner ears to register similar inputs, minimizing the sensory disagreements going to your head. If you’re reading a map or fixing your eyes inside the cabin, look out and focus on the horizon so your eyes send the same message your ears feel. If symptoms come on during maneuvers, slow it down, keep the aircraft straight and level or in a steady rate turn, and keep pitch and vertical changes to a minimum to let the feelings ease up.

Dealing with motion symptoms is different and unfortunately harder if you’re in the weather in IFR conditions. Start off by concentrating on your flying tasks and pay even more attention than usual to the Attitude Indicator and the artificial horizon. It’s the same principle as looking out at the horizon, except there’s nothing to see outside so you have to get your eye/ear orientation from your instruments. Open the vents to get some fresh cool air on your face and breathe supplemental oxygen if it’s available, but make sure there are no foul odors in the mask. Dealing with airsick passengers in the weather is tough too. Make sure they’re not trying to read emails or a book. Also, if they’re in the middle row facing backwards turn them around to face the direction of flight, as that will help get their ears and eyes sensing the same things. If you have a sick passenger and can switch people around, bring them forward and show them the AI and have them focus on the instruments with you. It also might help if they rest their hands on the yoke; just be careful and don’t let them get a death grip and fight you for control of the aircraft.

As I said above, repeated exposure to turbulence will help you get used to and adapt to the sensations from ear/eye conflicts. Getting familiar with the sensations and what works to ease the feelings brings you confidence and blunts anxiety and stress hormone release. There are some things you can do on the ground to avoid getting airsick in the first place. If you anticipate turbulence, be sure you’re familiar with the flight plan, where the weather is, and how long you’ll have to be in it. If you intend to practice unusual attitude flight or aerobatics, be sure to brief the maneuvers in advance to anticipate the motion of the aircraft. Eat light and have a snack 2-3 hours before you plan to fly, since an empty stomach is more prone to be upset in motion, but avoid large or spicy meals. Stay well hydrated but don’t have any alcohol in your system and don’t smoke. Practice making only slow, purposeful head movements in the cockpit without abrupt twisting or turning that sends more conflicting signals from your ears and throws your eyes off the horizon or instruments during flight.

More complicated methods that help people prone to motion sickness are called “visuospatial training.” The vocabulary has way too many syllables for me but data from clinical research shows that this type of training reduces the incidence and severity of motion sickness in about half of participants. It’s a program of mental and visual exercises ranging from pen and paper sessions requiring mental image manipulations and simulator sessions over a two-week period. Adding high-fidelity video gaming and using CAD (computer-aided design) image manipulation programs enhances the benefits of this type of training and benefits about two out of three of participants. The military uses a program called “G Awareness Maneuvers“ to prepare candidates for aerobatics and dogfighting. They do this with a series of brief flight maneuvers, gradually increasing in intensity, never progressing until the pilot is comfortable with the easier maneuvers. This can be useful in GA spin and stall training also, since it allows the pilot to get to a steady accommodation to the motion sensations.

The FAA doesn’t allow pilots to use standard motion sickness medications since they all cause drowsiness, impair thinking and problem solving, and cause visual disturbances. Your passengers can use these meds and the most effective is scopolamine, which can be taken as a skin patch or pill or both in bad cases. Scopolamine has the worst side effects, and that’s why pilots are prohibited from using it, but there are some more homeopathic treatments that have shown benefits without any side effects. Oncologists have used ginger root derivatives to prevent nausea from chemotherapy and anesthesiologists have found some benefits using ginger to reduce postoperative nausea that’s supported in clinical studies. The ship I was on recently had ginger candies on every deck for the same purpose and it seemed to help a lot of the passengers. There’s also some medical literature that elastic wristbands can have some benefit to reduce nausea after chemotherapy. This simple solution is based on traditional Chinese acupressure therapy to a specific pressure point in the wrist. The target is on the front of the forearm, about 1.5 inches from the wrist crease, called the P6 point in acupuncture. Lots of people use them but some of the benefit might be just placebo. Still it certainly causes no harm and wouldn’t hurt to try it out in the air.

If motion sickness is a recurrent problem for you it might be best to avoid flights into known turbulent conditions, which you can check in advance with PIREPS and on the Aviation Weather Center graphic turbulence charts. The safest thing to do if you get really sick in the air or you have a passenger who becomes incapacitated is to land, get on solid ground, and let the feelings pass and the weather clear. Just be sure to play lots of video games, eat light, chew ginger candies, and fly safe!

Kenneth Stahl, MD, FACS
Kenneth Stahl, MD, FACS is an expert in principles of aviation safety and has adapted those lessons to healthcare and industry for maximizing patient safety and minimizing human error. He also writes and teaches pilot and patient safety principles and error avoidance. He is triple board-certified in cardiac surgery, trauma surgery/surgical critical care and general surgery. Dr. Stahl holds an active ATP certification and a 25-year member of the AOPA with thousands of hours as pilot in command in multiple airframes. He serves on the AOPA Board of Aviation Medical Advisors and is a published author with numerous peer reviewed journal and medical textbook contributions. Dr. Stahl practices surgery and is active in writing and industry consulting. He can be reached at [email protected].

Related Articles