105 Flashcards
Define boyles, charles, dalton’s, fick’s, henry’s, Universal, Gay-Lussac’s and Graham’s Laws - give example of each
Boyle - Constant T, increase in volume with decrease in pressure -pneumoCharles - Constant P, increase in temp, increase in volume - helicopters fly in winterDalton - Total pressure of gas is the sum of all the partial pressuresFick’s law - rate of diffusion of gas is proportional to its partial pressure gradient, proportional to the surface area it is diffusing across and inversely proportional to the thickness of the membraneHenry - Concentration of gas in solution is proportional to its partial pressureUniversal gas law - PV = nRTGay-Lussac’s = increase in pressure, increase in temperatureGraham Law = diffusion of gas is inversely proportional to the square root of its molar mass
What is the definition of dysbarism?
Medical conditions arising from changes in pressure
Define the four types of hypoxia
Hypoxic hypoxia - inadequate PO2 (lack of O2 entering the blood) - no one getting on the train (reduce atmosphere is primary cause)
Histotoxic hypoxia - Cells can’t use O2 delivered (cyanide, alcohol, narcotics) - People get off the train, but they don’t know what to do when they get there
Stagnant hypoxia - No forward flow - train isn’t working - heart failure, MI, in flight enviroment - G Force
Hypemic hypoxia - Less train cars - (anemic hypoxia) - lack of hemaglobin molecules or lack of RBCs - most common forms are blood loss or anemia
At what altitude do pneumo’s double?
18,000 feet
Describe the four stages of hypoxia as they relate to altitude?
1) Indifferent stage - sea level to 10,000 - minor physiological changes, decrease night vision
2) Compensatory stage - 10,000 to 15,000 ft - drowsiness, poor judegement, impaired coordination, sounds drunk
3) Disturbance stage - 15,000 to 20,000 ft - Impaired flight control, impaired handwriting, impaired speech
4) Critical stage - above 20,000 - Circulatory failure
What are effective performance time and time of useful consciousness?
Effective performance time is the amount of time an individiual is able to perform useful duties in an environment of inadequate oxygen (20-30 mins at 18,000 feet)
Time of useful consciousness is the time between when oxygen is suddenly removed and when the person can no longer deliberately function - person can no longer take corrective or protective actions. (10 - 15 mins at 18,000 feet)
Effective performance time is less by about a 1/3
Discuss the unique layers of the earth’s atmosphere
Troposphere - sea level to 26000 (poles) 52000 (equator) - most weather occurs here
Tropopause - 26000 - 30000 (poles) 52000 - 60000 (equator)
Statosphere (above tropopause)
What are the 3 distinct zones of the atmosphere with relation to human physiology? What are the pressures in those zones?
Physiologic zone (sea level to 10000 ft),
Physiologic deficient zone (10,000 to 50000 ft)
Space equivalent zone (above 50,000 ft)
Physiologic zone 760 - 523 mm Hg
Physiologic deficient zone 523 - 87 mm Hg
In which physiological zone of the atmosphere are pressure suits required and why?
Space equivalent zone becuase of the decreased barometric pressure
What are aircraft usually pressurized to? (What method is used to do this?)
5,000 to 8000 feet (Isobaric control system)
Explain the four primary forces that enable the aircraft to perform all facets of flight
1) Lift
2) Thrust
3) Drag
4) Gravity
What are the modifiable factors affecting tolerance of the physiological stressors of flght?
IMSAFE + TH
Illness
Medication
Stress
Alcohol
Fatigure
Emotions
Tobacco
Hypoglycemia
What are the weight limits of the clam shell, back board, manta mat, stair chair, no 9, 35A (helijet), 35X and powercot?
Clam - 500
Backboard - 600
Manta - 800
Stairchair 500
No 9 350
35A 500
35X - 700/1100
PowerCot 700/1000
