Those "Moments"

From our earliest days practicing to become pilots we learned all about fog. The private pilot syllabus lists eight different types of fog, everything from advection fog to valley fog and a bunch in between. 

We learned about the weather conditions when fog would likely form and how to avoid it and all for good reason; it’s dangerous. Just searching the NTSB accident database over the last few years I found over 770 accident reports that list fog as a contributing factor. One of the most recent tragedies was the helicopter crash that killed Kobe Bryant, his daughter, and their friends in January.

Prussian General Carl von Clausewitz popularized another kind of fog way back in 1800; the “fog of war” has been proven in a number of military encounters and updated into more modern lingo as an “uncertainty in situational awareness.” There’s still another kind of fog, “brain fog.” We all have a haze descend over our brains every once in a while that we tend to just write off as one of those “moments.” Even though it feels like your head is wrapped up in cotton, brain fog is a real thing and not just a passing “mistiness” in your thinking and a momentary “uncertainty” of your own SA. We’ve spent a lot of time in these pages looking into William’s Error Producing Conditions. Brain fog can make every one of those factors more risky to aviators, and it can be as dangerous to our flight safety as any weather condition.

Brain fog symptoms are a bit vague, but it’s more than looking all over the house for your reading glasses that you just pushed back on top of your head a minute ago. Generally the symptoms include things like decreased ability to maintain focus, decreased problem-solving capacity, forgetfulness, and an inability to understand your surroundings or even momentarily not knowing where you are and what you’re doing. It sounds a lot like the normal age-related cognitive changes that we covered a while back in the post on “Who Will Guard the Guardians?” but there is a difference. It turns out that brain fog is a real medical entity and psychologists have a name for it, the “Syndrome of Brain Fogginess” (BF). They define it as a “transient cognitive impairment manifesting slow thinking, difficulty focusing, confusion, lack of concentration, forgetfulness, or a haziness in thought processes, slurred speech and possible gait or coordination disturbances.” Whatever you call it, all of it sounds bad for aviators.

There are lots of reasons our pilot heads might be in the clouds even when the sky is crystal clear. Some are easily understood and controllable, but some reasons are not well understood and can be an indication of very real medical problems. The easy ones for pilots are covered in the pages of the AOPA and this blog site such as hypoxia (wear your O2 mask), fatigue (don’t fly tired), stress (learn to relax), medications (don’t use cold medication and check the labels on others), hangover (no explanation needed), and distraction (concentrate). But if you’re experiencing these types of symptoms that are not related to the simple things, especially more frequently now, it’s time to see your doctor.

Several medical conditions can be associated with BF, including chronic fatigue syndrome, postural tachycardia syndrome, side effects of a bunch of drugs or toxins, metabolic or hormonal factors, neurological conditions like Parkinsonism, dementia, ischemic brain disease, carotid artery narrowing, and post-concussion syndrome. Another group of medical conditions linked to BF are inflammatory diseases, specifically Sjo╠łgren syndrome, lupus, multiple sclerosis, arthritis, and fibromyalgia. Diabetes (probably related to transient hypoglycemia), migraine headaches, hypothyroid states, anemia, depression, and Alzheimer’s disease are other known medical causes. With all of these possibilities for BF, a complete medical exam is in order. Along with a good physical exam, your doctor will likely order some blood tests to assess your glucose, liver, kidney, and thyroid functions, as well as check markers of inflammatory diseases, possible infection, and nutritional deficiency.

Once you and your doc have ruled out any underlying medical conditions, look for other causes. BF symptoms can be linked to factors in your diet like fad diets and probiotic use. Investigators at the Medical College of Georgia studied some common dietary fads and probiotics and found that a few of these fads could lead to large colonies of bacteria that overtake the small intestines. Bacteria are always found in the large intestines, but significant accumulation of bacteria in the small intestine is more rare and can be dangerous as it causes high levels of D-lactic acid production. D-lactic acid is known to be temporarily toxic to brain cells and interferes with cognition, problem solving, and sense of time. Some diets lead to two or three times the normal amount of D-lactic acid in the blood that can scramble your thinking for half an hour to many hours after eating. It is also possible to ramp up bacterial production of lactic acid by over eating sweet snacks with lots of sugar or drinking a lot of sugar-containing soft drinks.

Another common link to BF is a high homocysteine level in your blood. Homocysteine is an amino acid you get mostly from eating too much red meat. Also a bad thing about high levels of homocysteine is that it is linked to early development of heart disease. Some food allergies or sensitivities may cause brain fog that comes on after eating things like MSG (found in some spicy Asian food), aspartame, peanuts, and certain dairy products. There are a few dietary deficiencies that can also play a role in brain fog, specifically vitamin B-12 that supports healthy brain function, and several studies have linked vitamin B-12 deficiency to the syndrome.

So the good news is that there are a bunch of things to do for the occasional BF that are pretty simple. A good smart diet can reduce lots of the risks of developing BF; start by removing these possible trigger foods from your diet and see if the symptoms improve. While you are identifying and getting rid of the bad things in your diet, add a well-balanced vitamin supplement to your daily routine. Pilots also need to pay close attention to hydration, so when flying add an additional 6-8 ounces of water for every hour up in the air to compensate for the fluid you lose at altitude in low-humidity cockpit environments. This helps get lots of blood up to your head. Among other things you can control is smoking. Plenty of studies show that smokers are more likely to suffer from brain fog since smoking reduces the amount of oxygen reaching the brain. That is an even bigger risk to GA pilots who fly unpressurized airplanes. Smoking also increases risks of cardiovascular disease that cause BF symptoms due to brain infarcts (like stroke or transient ischemia known as TIAs), heart disease, and high blood pressure, which are all grouped into a basket known as “vascular dementia.”

Recognizing that you’re having momentary lapses like BF can be hard, so check yourself out with a really critical self-assessment right here on the ground and don’t even fly if you’re getting a bit foggy more often down here. While you’re doing your self-assessment, remember that exercise is critical. There are multiple benefits from exercise that not only builds up muscles and improves heart health but also benefits brain function and circulation. It also reduces the stress and anxiety that are rampant for all of us in these pandemic days. Managing stress helps reduce distractions and increase your focus. Sleep is crucial and a good workout also helps you get a restful night’s sleep. Be smart and be self-critical. Tune up your physical health like your diet, exercise, and sleep habits just like you tune up your airplane. That way your head will always function perfectly, help you avoid those moments of “uncertainty in situational awareness,” and keep you just as safe as your airplane will after a good tune-up.

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].
Topics: Pilot Health and Medical Certification, Pilot Health and Medical Certification

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