packet 16 Flashcards
normal quiet breathing
eupnea
temporary cessation of breathing
apnea
difficult or labored breathing
dyspnea
rapid breathing
tachypnea
descent of diaphragm causes stomach to bulge during inspiration
diaphragmatic breathing
just rib activity involved
costal breathing
in and out
amount air moved during quiet breathing
tidal volume
minute ventilation is amount of air moved in a minute
MVR
amount you can breathe either in or out above that amount of tidal volume
reserve volume
permanently trapped
1200 mL permanently trapped air in system
residual volume
21% O2, 79% N2 and .04% CO2 (methane????)
air
14% O2, 79% N2 and 5.2% CO2
alveolar air
16% O2, 79% N2 and 4.5% CO2
expired air
alveolar air has less O2 since absorbed by blood
mystery—–expired air has more O2 & less CO2 than alveolar air?
Anatomical dead space = 150 ml of 500 ml of tidal volume
observations of composition of ari
Quantity of a gas that will dissolve in a liquid depends upon the amount of gas present and its solubility coefficient
Breathing O2 under pressure dissolves more O2 in blood
Henry’s law
Clinical application of Henry’s law
Use of pressure to dissolve more O2 in the blood
treatment for patients with anaerobic bacterial infections (tetanus and gangrene)
anaerobic bacteria die in the presence of O2
Hyperbaric chamber pressure raised to 3 to 4 atmospheres so that tissues absorb more O2
Used to treat heart disorders, carbon monoxide poisoning, cerebral edema, gas embolisms
hyperbaric oxygenation
Gases diffuse from areas of high partial pressure to areas of low partial pressure
Exchange of gas between air & blood
Deoxygenated blood becomes saturated
Compare gas movements in pulmonary capillaries to tissue capillaries
external respiration
Depends upon partial pressure of gases in air
p O2 at sea level is 160 mm Hg
10,000 feet is 110 mm Hg / 50,000 feet is 18 mm Hg
Large surface area of our alveoli
Diffusion distance is very small
Solubility & molecular weight of gases
O2 smaller molecule diffuses somewhat faster
CO2 dissolves 24X more easily in water so net outward diffusion of CO2 is much faster
disease produces hypoxia before hypercapnia
lack of O2 before too much CO2
rate of diffusion of gases
Exchange of gases between blood & tissues
Conversion of oxygenated blood into deoxygenated
Observe diffusion of O2 inward
at rest 25% of available O2 enters cells
during exercise more O2 is absorbed
Observe diffusion of CO2 outward
internal respiration
more exhalation because greater CO2 levels which leading to lower pH or acidosis
hyperventilation
less exhalation because lower CO2 level which leads to alkalosis or pH high
hypoventilation
Oxyhemoglobin contains 98.5% chemically combined oxygen and hemoglobin
inside red blood cells
Does not dissolve easily in water
only 1.5% transported dissolved in blood
Only the dissolved O2 can diffuse into tissues
Factors affecting dissociation of O2 from hemoglobin are important
Oxygen dissociation curve shows levels of saturation and oxygen partial pressures
oxygen transport in blood
Blood is almost fully saturated at pO2 of 60mm
people OK at high altitudes & with some disease
Between 40 & 20 mm Hg, large amounts of O2 are released as in areas of need like contracting muscle
hemoglobin and oxygen partial pressure
As acidity increases, O2 affinity for Hb decreases =
Bohr effect
H+ binds to hemoglobin & alters it
O2 left behind in needy tissues
acidity and oxygen affinity for Hb
As temperature increases, more O2 is released
Metabolic activity & heat
More biphosphoglycerate (BPG), more O2 released
RBC activity
hormones like thyroxine & growth hormone
temperature and oxygen release
100 ml of blood carries 55 ml of CO2
Is carried by the blood in 3 ways
dissolved in plasma
combined with the globin part of Hb molecule forming carbaminohemoglobin
as part of bicarbonate ion
CO2 + H2O combine to form carbonic acid that dissociates into H+ and bicarbonate ion
carbon dioxide transport
carbon dioxide transport by blood in 3 ways
- dissolved in plasma (7%)
- combined with globin part of hemoglobin molecule formation carbaminohemoglobin
- bicarbonate ion
primary buffer ion
