Aeromedical Factors Flashcards
What is Hypoxia?
State of oxygen deficiency in the body sufficient to impair functions of the brain and other organs.
Where does Hypoxia usually occur?
Most significant effects of altitude hypoxia usually do not occur in the normal, healthy pilot below 12,000 ft. From 12-15k ft, judgment, memory, alertness, coordination, and ability to make calculations are impaired. Headache, drowsiness, dizziness and either a sense of well-being or belligerence occur. Effects worsen over 15,000 ft.
How can Hypoxia be avoided?
Heed factors that reduce tolerance to altitude, enrich the air with oxygen from an appropriate oxygen system and maintain a comfortable, safe cabin pressure altitude. Optimum - use supplemental O2 above 10k feet during day and above 5k feet at night.
What factors can make a pilot more susceptible to Hypoxia?
The altitude at which significant effects occur can lower by a number of factors. Carbon monoxide, anemia and certain meds can reduce the capacity of your blood to carry O2. Small amounts of alcohol & low doses of certain drugs (antihistamines, tranquilizers, sedatives and analgesics via their depressant action.) Extreme heat/cold, fever and anxiety increase the body’s demand for oxygen, an hence its susceptibility to hypoxia. Cyanosis of skin.
What is Hyperventilation?
(Abnormal increase in the volume of air breathed in and out of the lungs.) Can occur subconsciously when a stressful situation is encountered in flight. Results in a significant decrease in the carbon dioxide content of the blood.
What symptoms can a pilot expect from Hyperventilation?
Light-headedness, suffocation, drowsiness, tingling in the extremities, and coolness. Incapacitation can eventually result from uncoordination, disorientation, and painful muscle spasms. Unconsciousness.
How can a Hyperventilating condition be reversed?
Symptoms will subside within a few minutes after rate and depth of breathing are consciously brought back to normal. The buildup of C02 can be hastened by controlled breathing in and out of a paper bag.
What is Carbon Monoxide Poisoning?
Colorless, odorless, tasteless gas contained in exhaust fumes. When inhaled, even in small quantities over a period of time, it can significantly reduce the ability of the body to carry oxygen. Effects of hypoxia can occur.
How does Carbon Monoxide Poisoning occur? What symptoms should a pilot be alert for?
Leaked exhaust fumes coming into cockpit.
Odor of exhaust, headache, drowsiness or dizziness while using the heater should suspect this.
What action should be taken if a pilot suspects Carbon Monoxide Poisoning?
Immediately shut off heater and open all air vents. If symptoms are severe or continue after landing, medical treatment should be sought.
What is the cause of Motion Sickness? Symptoms?
Cause by continued stimulation of the inner ear which controls the sense of balance. Symptoms are progressive - loss of appetite, saliva collecting, perspiration, nausea, disorientation, headaches and possible vomiting. Pilot could become incapacitated.
What action should be taken if a pilot or his passenger suffers from motion sickness?
If piloting, open air vents, loosen clothing, use supplemental oxygen and keep the eyes on a point outside the airplane. Avoid unnecessary head movements. Terminate flight ASAP.
What is Ear Block?
As cabin pressure decreases during ascent, expanding air in the middle ear pushes the Eustachian tube open. Air escapes down the nasal passages and equalizes in pressure with the cabin pressure. During descent, pilot must periodically open the tube to equalize pressure. Upper respiratory conditions, nasal allergies, etc can produce enough congestion to make equalization difficult. Consequently the pressure difference could cause a block which produces severe pain and loss of hearing that can last from several hours to several days.
What action can be taken to prevent Ear Block from occurring in flight?
Swallowing, yawning, tensing muscles in the throat or closed mouth/nose pinch and blow thru nose. Also - don’t fly with an upper respiratory infection or nasal allergic condition!
What regulations apply and what common sense should prevail concerning the use of alcohol?
No flight for 8 hours after any alcoholic beverage.
Under 0.04 % blood/alcohol level.
