Chapter 23 respiratory part 3 Flashcards
optimal gas exchange requires the coupling of _______ and _______
ventilation and perfusion
What the relationship between alveolar ventilation and blood flow to the alveoli called
ventilation perfusion coupling
What is the amount of gas reaching alveoli
ventilation
What is the blood flow in pulmonary capillaries
perfusion
What is blood that is not completely oxygenated called
shunted blood
What occurs due to deoxygenated blood from bronchi/bronchioles mixing blood in pulmonary veins
anatomical shunt
What occurs from a combo of anatomical shunt and incompletely oxygenated blood from alveoli (1-2% of CO)
physiological shunt
What can occur is there is insufficient blood flood to the alveoli and insufficient air flow
disruption
Disruption from less blood flow can occur from (2)
Post MI (decrease CO)
body position
(standing = increase gas exchange)
Disruption from less ventilation can occur from (2)
pulmonary capillaries not fully oxygenated (asthma attack)
pneumonia/pulmonary edema (fluid build up)
Ventilation-perfusion coupling is controlled by what mechanism
local autoregulatory mechanism
Partial pressure of oxygen, the amount of O2 dissolved in the blood controls perfusion via change in __________
arterial diameter
partial pressure of CO2, amount of CO2 within arterial or venous blood controls ventilation via change in __________
bronchiole diameter
What is used by cells to make ATP from glucose
O2
What percentage of O2 is bound to Hgb within RBCs (heme portion =carry up to 4 O2 molecules)
98.5%
What percentage of O2 is dissolved in plasma?
1.5%
What is formed as a by-product of breakdown of glucose when cells use O2 to produce ATP
CO2
What percentage of CO2 is converted to bicarbonate ion (HCO3)
70%
What percent of CO2 is bound is Hgb within RBCs
23%
What percent of CO2 is dissolved in plasma
7%
What is a protein in the RBC that transports O2 and CO2 in the blood
hemoglobin
There is tight regulation of CO2 in the blood because excessive CO2 can lead to what?
acidic blood (low pH)
What binds to alpha and beta globin chains of Hgb
CO2
What effect describes the relationship between the amount of oxygen bound to Hgb and the amount of CO2 bound
(less O2 bound means more CO2 can bind)
Haldane effect
In the tissue, CO2 diffuses into the ______ and into the _____ cells
plasma
blood cells
In the tissue, In RBC, CO2 reacts with water to form what?
carbonic acid (H2CO3)
In the tissue, What enzyme catalyzes the carbonic acid formation
carbonic anhydrase
In the tissue, Carbonic acid will dissociate to form what two ions
HCO3- and H+
In the tissue, HCO3- floats out of RBC, but the electrical neutrality is kept from the diffusion of what ion into the RBC
Cl-
In the tissue, What Ion combines with Hgb to promote O2 release
H+
In the lungs, CO2 diffuses from RBC and plasma into the ______
alveoli
In the lungs, carbonic anhydrase catalyzes the formation of ______ and ______ from H2CO3-
CO2 and H2O
In the lungs, bicarb ions and H+ combine to replace
H2CO3-
In the lungs, as HCO3- diffuses into the RBC, electrical neutrality is kept by ______ flowing out
Cl-
In the lungs, H+ ions are released from the Hgb, promoting the binding of ______
O2
What condition is inadequate oxygen delivery to the body tissues called?
hypoxia
Hypoxia is viewed as a _______ when Hgb saturation is <75% (see in nails and mucosa)
cyanotic hue
what classification of hypoxia is due to decreased RBCs or decreased/abnormal Hgb
anemic
what classification of hypoxia is due to impaired/blocked blood circulation
ischemic
what classification of hypoxia is due to reduced arterial PO2, abnormal V-Q coupling, pulmonary diseases, or air with decreased O2
hypoxemic
What is an odorless colorless gas that is the leading cause of death from fire
carbon monoxide poisoning
Hgb has a ____ greater affinity for CO than Oxygen
200x
Sx of CO poisoning (3)
confusion, HA, Skin cherry red
Tx for CO poisoning (2)
Hyperbaric therapy or 100% oxygen until CO cleared from body
What is true or normal Respiratory rate and rhythm
EUPNEA
What is the increase in rate and depth of breathing that exceeds the body’s need to remove CO2, anxiety attack
hyperventilation
You should never hyperventilate prior to swimming or you will
drown
What is low CO2 levels in the blood as blow off CO2 leads to constriction of brain BVs, which leads to low brain perfusion, which leads to cerebral ischemia, which leads to dizziness/fainting
hypocapnea
what are Sx of hypocapnea
tingling
tetany of face and hands from hypocalcemia as pH rises
How do you counteract hypocapnea
breathe in paper bag
what means breathing cessation
apnea
Ventilation increases 10-20 fold during vigorous ______
exercise
What is increased ventilation to match metabolic needs (not alter O2 and CO2 levels)
hyperapnea
Sudden increase in altitude from sea level to >8000 feet lowers what 2 things
PO2 and Atm pressure
high altitude sickness is also called …
acute mountain sickness
Sx of AMS
HA
SOB
Nausea
Dizzy
Severe AMS can cuase edema where (2)
cerebral and pulmonary
Long term AMS acclimates via increased ____ and less O2 available
ventilation
long term AMScauses the kidneys to preoduce ________ and bone marrow to produce ________
erythropoietin
RBCS
Tx for AMS (3)
dexamethasone (diamox)
O2
lower altitude
