Aeromedical Factors

Some drugs that are classified as neither stimulants nor everyone metabolizes medications differently. However, depressants have adverse effects on flying. For example, five times the dosing interval is a reasonable rule of thumb. some antibiotics can produce dangerous side effects, such as balance disorders, hearing loss, nausea, and vomiting. Altitude-Induced Decompression Sickness (DCS) While many antibiotics are safe for use while flying, the Decompression sickness (DCS) describes a condition infection requiring the antibiotic may prohibit flying. In characterized by a variety of symptoms resulting from addition, unless specifically prescribed by a physician, do exposure to low barometric pressures that cause inert gases not take more than one drug at a time, and never mix drugs (mainly nitrogen), normally dissolved in body fluids and with alcohol because the effects are often unpredictable. tissues, to come out of physical solution and form bubbles. Nitrogen is an inert gas normally stored throughout the The dangers of illegal drugs also are well documented. human body (tissues and fluids) in physical solution. When Certain illegal drugs can have hallucinatory effects that occur the body is exposed to decreased barometric pressures (as in days or weeks after the drug is taken. Obviously, these drugs flying an unpressurized aircraft to altitude or during a rapid have no place in the aviation community. decompression), the nitrogen dissolved in the body comes out of solution. If the nitrogen is forced to leave the solution too 14 CFR prohibits pilots from performing crewmember rapidly, bubbles form in different areas of the body causing a duties while using any medication that affects the body in variety of signs and symptoms. The most common symptom any way contrary to safety. The safest rule is not to fly as a is joint pain, which is known as “the bends.” [Figure 17-10] crewmember while taking any medication, unless approved to do so by the FAA. If there is any doubt regarding the effects What to do when altitude-induced DCS occurs: of any medication, consult an AME before flying. • Put on oxygen mask immediately and switch the regulator to 100 percent oxygen. Prior to each and every flight, all pilots must do a proper physical self-assessment to ensure safety. A great mnemonic, • Begin an emergency descent and land as soon as covered in Chapter 2 on Aeronautical Decision-Making, possible. Even if the symptoms disappear during is IMSAFE, which stands for Illness, Medication, Stress, descent, land and seek medical evaluation while Alcohol, Fatigue, and Emotion. continuing to breathe oxygen. • If one of the symptoms is joint pain, keep the affected For the medication component of IMSAFE, pilots need to area still; do not try to work pain out by moving the ask themselves, “Am I taking any medicines that might affect joint around. my judgment or make me drowsy? For any new medication, • Upon landing, seek medical assistance from an FAA OTC or prescribed, you should wait at least 48 hours after medical officer, AME, military flight surgeon, or the first dose before flying to determine you do not have any a hyperbaric medicine specialist. Be aware that a adverse side effects that would make it unsafe to operate an physician not specialized in aviation or hypobaric aircraft. In addition to medication questions, pilots should medicine may not be familiar with this type of medical also consider the following – problem. • Do not take any unnecessary or elective medications; • Definitive medical treatment may involve the use of • Make sure you eat regular balanced meals; a hyperbaric chamber operated by specially-trained • Bring a snack for both you and your passengers for personnel. the flight; • Delayed signs and symptoms of altitude-induced DCS • Maintain good hydration - bring plenty of water; can occur after return to ground level regardless of presence during flight. • Ensure adequate sleep the night prior to the flight; and • Stay physically fit. DCS After Scuba Diving Scuba diving subjects the body to increased pressure, which Additionally, you should wait at least five maximal dosing allows more nitrogen to dissolve in body tissues and fluids. intervals, the time between recommended or prescribed [Figure 17-11] The reduction of atmospheric pressure that dosing, (e.g., a dosing interval of 5 to 6 hours would require accompanies flying can produce physical problems for scuba you to wait 30 hours) before flying after taking any medication divers. A pilot or passenger who intends to fly after scuba that has potentially adverse side effects (e.g., sedating or diving should allow the body sufficient time to rid itself of dizziness). Observing the recommended dosing interval excess nitrogen absorbed during diving. If not, DCS due to doesn’t eliminate the risk for adverse side effects because 17-18