Flight Physiology Flashcards Preview

A+ Test Prep > Flight Physiology > Flashcards

Flashcards in Flight Physiology Deck (31)
Loading flashcards...
1
Q

Barotitis Media

A

Boyles law, air in middle ear expands on ascent, escapes via Eustachian tube (dumps into nasopharynx).

  • on descent, atmospheric pressure increases on ear drum, air is drawn back into ear. If tube is blocked, air cannot get back in,
  • descent problem.
2
Q

Barodontalgia

A

Air trapped beneath dental work. (New or foreign)

  • expanding air cannot escape. Pushed down on nerve.
  • Ascent problem
  • Slow ascent. Analgesics.
3
Q

Barosinusitis

A

Boyles law.
-air trapped in sinuses.
Ascent / Descent problem. Expanding air cannot escape.
Pressure in sinus tissues,
-slow climb out, nasal decongestions (neosynephrine), analgesics

4
Q

Barobariatrauma

A

Boyles law

  • nitrogen absorbed in adipose tissue, expands on rapid ascent.
  • attempts to release into plasma then to lungs.
  • cannot blow off quickly enough = nitrogen toxicity, bends
  • FiO2 to 100%
5
Q

ETT considerations for Boyles law.

A

ETT cuff not typically an issue in RW

  • 30,000 ft plus requires replacement w/ water
  • cabin decompression = cuff rupture.
6
Q

Boyle law Cast considerations

A

Tissue under cast is rich with air, can expand.

  • casts less than 7 days old require bi-valve
  • cut on medial and radial aspect, wrap with ace bandage.
7
Q

Chest tube considerations concerning Boyle’s law

A

Has moving through tube into collection device.

  • needs vented to atmospheric air so it can equalize.
  • otherwise gas will expand on ascent - escapes into chest.
  • pop hemilick valve in line with the atrium.
8
Q

Charles law

A

At constant pressure, volume of a gas is directly proportionate to the absolute temperature of the gas.

  • heat a gas, volume expands,
  • cool a gas, volume contracts
  • V1/T1 = V2/T2
9
Q

Celsius temp drops 1 degree for q meters climbed.

A

100 m

10
Q

Boyle’s Law

A

Volume of a gas is inversely proportionate to its pressure under constant temp.
-P1V1=P2V2

11
Q

Gay-Lussac’s Law

A

Same as Charles law only vessel is fixed container
-directly proportional between temp and pressure.
Aeromedical application: O2 tank, cools on climb, O2 pressure drops

12
Q

Henry’s law

A

At constant temp: the amount of a given gas dissolved in a type and volume of liquid is directly proportional to the partial pressure if that gas in equilibrium with that liquid.

13
Q

Henry’s law aeromedical application, cabin decompression

A

Leer jet at 30k feet- explosive decompression
-partial pressure of plasma O2 is greater than that of lungs
-O2 will not dissolve for, lungs into plasma
-O2 will reverse from plasma into lungs
-Results in sudden LOC
(Another application is decompression sickness)

14
Q

Graham’s law

A

Law of gaseous diffusion.
-diffusion rate of a gas through a liquid medium is directly related to the solubility of the gas and inversely related to the square root of its density.
-at equal pressures/temps, gases with smaller mass diffuse faster,
O2 smaller than CO2, but CO2 more soluble.
-CO2 diffuses across fluid faster than O2

15
Q

Factors that influence Graham’s law

A

Surface area, diffusion gradient, diffusion distance, molecular size, solubility.

16
Q

Dalton’s Law

A

The total pressure of a gas mixture is the sum of the partial pressures of all gases in the mixture.
Pt=P1+P2+P3…
P1 = fractional [P1] x barometric pressure.

17
Q

DEATH - factors effecting flight stressors

A
Drugs
Exhaustion (predisposes spatial disorientation)
Alcohol
Tobacco
Hypoglycemia
18
Q

Night vision loss, smokers considerations

A

Loss of night vision: 5000 msl

Smokers loose 4000 ft of night vision capabilities

19
Q

Rods vs cones

A

Rods: night vision, periphery of eye
Cones: day vision, center of eye.

20
Q

What is most susceptible to hypoxia?

A

Eyes, eyesight.

21
Q

1 ATM weighs

A
  1. 7 pounds, or 760 Hg (torr)
    - per square inch
    - on perfect day: 59 degrees F
22
Q

Atmospheric change

A

Greater atmospheric change noted as sea level with ascent than starting at higher elevation.

  • ascent, pressure becomes less (0.5 ATM or 389 Hg at 18,000 ft)
  • as you dive, 1 ATM = 33 feet under water..
23
Q

Diver has dove 66 feet, how many atmospheres are in him?

A

3 atmospheres:

  • 2 atmospheres of water
  • 1 atmosphere of air
24
Q

Physiological Zone

A

Sea level to 10,000 ft.

Great compensation unless ailments exist

25
Q

Physiological Deficient zone

A

10k to 50k ft

  • healthy individuals notices compensatory attempts
  • most would not experience significant symptoms
26
Q

Space-equivalent Zone

A

50k-250k ft

-requires assistance

27
Q

Space

A

250k or higher

28
Q

Hypoxia hypoxia

A

Deficiency in alveolar O2 exchange (aka altitude hypoxia)

-drop in available O2, apnea, altitude, venous mixing

29
Q

Histotoxic Hypoxia

A

Failure of the tissues ability to use presented O2

  • commonly results of poisoning, or metabolic disorders
  • cyanide (not only displaces O2 from Hgb, also interferes with mitochondrial ability to utilize O2) interferes wi electron transport chain in cellular respiration.
30
Q

Stagnant hypoxia

A

Reduced cardiac output, or pooling of blood

  • heart failure, PE, Shock
  • able to get O2 from lungs, blood is not going anywhere.
  • localized stagnant hypoxia: compartment syndrome
31
Q

Hypemic Hypoxia

A

Reduction in the O2 carrying capacity in the blood