DSA respiratory adaptations

Question 1

what is hypoxia, anoxia, hypoxemia

Answer 1

hypoxia: refers to inadequate oxygen available for use by the tissues

Anoxia: then refers to the total absence of oxygen being delivered to the tissue

Hypoxemia: is the proper term for low oxygen content in the blood

Question 2

Hypoxix Hypoxia

Answer 2

the PaO2 is below normal because either the alveolar PO2 is reduced (altitude) or the blood is unable to equilibrate fully with the alveolar air (diffusion impairments)

Question 3

Anemic hypoxia

Answer 3

lungs are in perfect working conditions but the oxygen carrying capacity of the blood has been reduced

carbon dioxide can cause the anemia since it binds to hb with such high affinity and reduces the oxygen carrying capacity making it so the tissues do not get sufficient oxygen to maintain their metabolic needs

Question 4

Circulatory hypoxia

Answer 4

lungs are working fine and the blood can carry sufficient oxygen, however, the tissue is not recieving sufficient oxygen because the heart cannot pump the blood to the tissue (or the arteries are blocked)

sickle cell anemia can lead to circulatory hypoxia since the RBC can get stuck in blood vessels

Question 5

Histotoxic hypoxia

Answer 5

histotoxic literally means that the cells have been poisoned

there is no problem getting the oxygen to the tissue - the lungs and circulatory system are just fine

however the tissue is unable to used the oxygen

cyanide leads to histotoxic hypoxia by poisoning the systems that utilize oxygen to create energy and prevent them from using the oxygen

lots of oxygen there but cant be used

Question 6

what level does the chemoreceptor monitor?

Answer 6

they are responsible for detecting changes in the arterial carbon dioxide levels by measuring the changes in hydrogen ion concentration of the CSF

this is because the carbonic anhydrase in the CSF is near the chemoreceptors

Question 7

in the early stages of COPD do patients have issues with CO2 levels or O2 levels?

Answer 7

O2 because the diffusion constant for CO2 is much higher

Question 8

Resetting the central chemoreceptors

Answer 8

since an individual will try to increase ventilation to compensate for lack of Oxygen which will lower the levels of paCO2 the neurons will accept the PaCO2 levels of 30 as normal

it does because the composition of CSF is going to compensate for the altered CO2 and pH, since there is lower CO2 and more basic pH the CSF is going to bring the pH back to normal so the CSF will have a more acidic pH than blood

Question 9

Chronic hypercapnia

Answer 9

now retaining CO2 leads to respiratory acidosis as well as acidifying the CSF

acidification of CSF will stimulate breathing but this will lead to an acidic pH in the CSF so choroid plexus will have to adjust CSF back to normal and then accept a higher PaCO2

more bicarbonate in the CSF

Question 10

physiological effects of altitude

Answer 10

decrease in pressure of the atmosphere leads to a decrease in the PiO2 therefore a decrease in the PAO2

therefore the percent of saturation of the oxygen decreases as well

Question 11

what is the acute response to altitude

Answer 11

Increase in ventilation in response to the hypoxia

increase in ventilation is a decrease in CO2 if the metabolic production doesnt change

Decreased in PaCO2 causes a decrease in firing of the central chemoreceptors leading to an increase in ventilation

Question 12

what is the process of acclimatization

Answer 12

long term affects of being at a hypoxia/hypocapina environment

CSF pumps more H+ or decrease HCO3- to decrease pH to allow peripheral chemoreceptors to fire to increase ventilation, therefore central chemoreceptors maintain a lower PaCO2

kidney increase in production of erythropoietin to produce more red blood cells to increase hemocrit nd Hb content and increasing oxygen carrying capacity

cells also increase number and size of the mitochondria

Question 13

altitude sickness

Answer 13

sympotms include headache, irritabillity, insomnia, dyspnea, nauseam and vomitting for a week to become acclimatized

leads to cerebral edema due to the cerebral vasculature dilating from the hypoxia

pulmonary edema is another side effect due to increase in pulmonary vascular permeabillity and an increase in pulmonary hypertension due to the hypoxic vasoconstriction

Question 14

Physiologic effects of diving

Answer 14

increase in barometric pressure by every 10 m of water you increase by 1 atm plus 1 atm for the air

run into problem of getting too much gas in our systems

Question 15

effects of hyperbaric pressure: oxygen

Answer 15

too much oxygen leads to irritation of the respiratory pathway, ringing of the ears due to large amounts of superoxide anion and peroxide

these related to the FiO2 and the total pressure you are exposed to 100 percent vs the 21percent

can affect infants in growth especially retina and lungs,

Question 16

Effects of hyperbaric Pressure: nitrogen

Answer 16

nitrogen also gets to equilibrium in our alveoli at PaN2
(makes up 79 percent of the air)

increased pressure more nitrogen dissolves in our plasma and can lead to nitrogen narcosis which similar effects as alcohol on neurons

in ascension must go slow so that the nitrogen that is dissolved can get to the lungs and be converted to gas

if go to quick the nitrogen becomes a gas in our body fluids and vessels resulting in the bends or decompression sickness

severe pain and neurological issues and will appear within 30 minutes of surfacing

can also happen if there is rapid decompression

Question 17

hyperbaric pressure: Air embolism

Answer 17

during ascent the diver must have the glottis open so that expanding air can leave the lungs

if not allowed to leave then the air goes into the blood and can rupture the pulmonary veins