Cause of movement of gas from one point to another?
partial pressure difference
pO2 of alveolar and pulmonary arterial blood and blood leaving the aorta
104 and 40 and 95
Two reasons for increase in oxygen diffusion capacity during exercise?
- increase in open pulmonary capillaries, more ideal retaliation perfusion ratio
- blood is fully oxygenated about 1/3 of the way through the capillary
ejection volume of rt ventricle to lt
- left ejects 2-3% more volume due to addition of bronchial circulation
- shunt flow
an increase in blood flow through a tissue will increase the tissues pO2
vita B deficiency that affects cell oxygen utilization
disables cytochrome oxidase activity, cell can not utilize oxygen
what two factors determine tissue pO2?
delivery and use of oxygen
pCO2 intracellular, interstitial, arterial blood, venous blood
46, 45, 40, 45
End effect of an increase in tissue metabolism on interstitial pCO2
as pO2 rises so does the saturation of Hb
amount of oxygen 1g of Hb can combine with?
amount of O2 (ml) in 100ml of blood
under normal conditions how much oxygen is delivered to the tissues per 100 ml of blood?
5ml, can increase to 15ml during heavy exercise
What factors cause muscle pO2 to stay constantly at 40mmHg during exercise
- increase in cardiac output
- decrease in affinity for Hb, raise in temp CO2, 2.3DPG and decrease in pH
percentage of blood that gives up its oxygen as it passes through the capillaries
as oxygen is delivered to the tissue Hb releases more oxygen into the blood
chronic hypoxic condition increase what?
2,3, DPG (poor tissue blood flow)
What is the main limiting factor what blood pO2 is greater then one for tissue metabolism?
effects of oxygen poisoning?
brain convolutions and death
What binds to the same site on Hb and oxygen but with a high affinity?
CO, partial pressure of 0.4 will allow CO to equally compete with O2 for binding to Hb. 0.6 is lethal
In CO poisoning what is the affect on blood pO2?
- normal, no obvious signs of hypoxia
- since pO2 is not depressed there is no low O2 feedback mechanism to increase respiration
- can treat with pure oxygen and CO2 in the blood to increase breathing
amount of CO2 transported from the tissues to the lungs in the blood per 100ml blood
- CO2 is higher in the venous blood causing an increase in production of H2CO3, this then dissociates and the H is buffered by Hb and the bicarb is exchanged for Cl. The chloride content of venous blood is less then arterial blood
- Water moves into the cell to maintain the osmotic equilibrium and causes the cell to swell.
- carbonic anhydrase inhibitor, can cause tissue pCO2 to reach 80
what is carbaminohemaglobin?
- CO2 bound to the terminal amine group of Hb
- pKa is around 7 so 50% is available at blood pH
volume percent change for CO2
52in venous blood to 48 in arterial, 4ml/100ml blood
What is the Haldane effect?
- the binding of oxygen to Hb displaces CO2 from the blood in the lungs
- The combination of oxygen with Hb causes Hb to become a stronger acid
- The more acidic Hb has less affinity for CO2 at the terminal amine group
- The increased acidity of Hb causes it to release more H that in turn bind with bicarb and form water and CO2, the CO2 is released from the lungs
- This effect doubles the amount of CO2 released from the blood in the lungs and double the amount picked up in the tissues. from 2ml to 4ml.
Normal pH of arterial and venous blood?
7.41 and 7.37
Respiratory exchange ratio?
- volume percent of CO2 over the volume percent of O2
- Usually in the range of 82 %
- using mainly carbohydrates for metabolism increases
- using fates for metabolism decreases
- Decreases in the fasting and starved states