Fly Well: Is your wiring firing correctly?

Neurology knowledge for the pilot

August 5, 2014

Jonathan Sackier

During preflight we check switches; inoperative systems may be caused by defective items, blown fuses, or dodgy wiring. But what if your wiring is the problem? Don’t blow a fuse from overload; let’s explore a few common and interesting human wiring issues.

Our nervous system is astounding. Stimulating one of our senses, electrical nerve impulses travel at light speed, jumping across synapses—relays ensuring messages are delivered appropriately. The brain processes information instantaneously, colored by prior experience, intellect, and instinct; appropriate action is taken.

This complex, elegant mechanism can be adversely affected by internal problems or from adjacent or supporting systems; the aviation corollary would be a burned-out bulb for the former, or an exhaust hole blowing hot gas onto a wiring bundle for the latter.

The brain is our flight computer and relies on a good supply of well-oxygenated blood, otherwise neurological problems ensue. Referring to that great movie, as we magnificent men (and women) in our flying machines go up, tiddly up, and hopefully come down, tiddly down in organized and not chaotic fashion, ensuring there is oxygen for our blood to carry is key. With age, heart function deteriorates, blood vessels narrow, and lungs lose efficiency; all are exacerbated by being overweight, unfit, or smoking. So even if you do not routinely use supplemental oxygen, reconsider with each passing year, especially at night. When tired or at altitude, if you notice narrowed visual field, pins and needles, headache, or other sensations, breathe oxygen, descend, and get examined for a precipitating cause. If symptoms recur or manifest on the ground, get to a doctor “FAST”—Facial drooping, arm weakness, speech difficulty—signs of a stroke, which is brain damage from impaired blood supply.

Backache is common; a sedentary lifestyle, obesity, and age all contribute. Spinal bony vertebrae are bound together by tough, fibrous ligaments and separated by spongy, resilient discs acting as shock absorbers. If a disc outer core pops, its gelatin-like interior presses on nerves traveling to and from the spinal cord. Disc intrusion nerve damage produces symptoms in the area served by that nerve such as numbness or a weak foot. Such symptoms merit urgent attention, or damage might become permanent.

Diabetes is caused by glucose-processing issues, but may induce wiring worries. For instance, diabetes is a frequent cause of blindness, and nerve damage elsewhere may cause neuropathy—“sick nerves”—experienced as severe, unremitting pain; loss of bladder, bowel, or sexual function; and inability to register touch. None of these is commensurate with a long and happy flying career, so avoid diabetes like the plague it is; eat well, exercise, watch your weight, and have regular checkups.

Infections also can cause nerve nightmares. A common example is Lyme disease, caused by a black-legged deer tick, which carries a bacteria, Borrelia burgdorferi. Soon after a bite, a red, migrating “bulls-eye” rash may appear. We doctors call that erythema migrans, which is medispeak for “a red rash that migrates around the body.” Known for causing muscle and joint pains, Lyme also produces Bell’s palsy, facial nerve paralysis where one side of the face droops. In regions and seasons where ticks abound, wear long pants and shirts; apply bug spray; and check for ticks after a walk, carefully removing any with fine tweezers. If a fever or rash develops, see your doctor for treatment.

Montel Williams, well known as a TV personality, was a decorated officer who considered a military aviation career, but visual field disturbance issues precluded him from flying. Eventually confirmed as having multiple sclerosis (MS), he now deals with gait and neuropathy symptoms. A disease usually associated with Caucasian women, Montel’s delayed diagnosis was partly because as an African-American male he did not fit the profile; his vision issues probably were an early indicator. The condition need not preclude flight. Currently there are 49 first class, 15 second, and two third class medicals issued to pilots with MS. Some MS drugs are allowable, although the FAA does require documentation—a perfect place for Pilot Protection Services to be helpful.

Prevention always is preferable; leading a healthy lifestyle is paramount. If problems arise, seek help early, deal with the problem, and then address how it will impact flying—but do not give up. Montel said it best: “I have MS but MS does not have me.”

Dr. Jonathan Sackier is a British-trained medical professional and private pilot who now lives in Virginia.

Email jonathan.sackier@aopa.org

Jonathan Sackier