Physiology of gas transport Flashcards
What is the typical amount of O2 dissolved in blood?
0.3 mL O2/100 mL blood
How does PaO2 affect O2 binding with hgb?
High PaO2 increases O2 binding to hgb, while low PaO2 causes release of O2 from hgb
When does the oxygen dissociation curve normally flatten out?
When PO2 is above 70 mmHg
What is the normal O2 capacity of hgb?
20.1 mL O2/100 mL of blood
What can cause the oxygen dissociation curve to shift to the right?
Decreased pH
Increased PaCO2
Increased 2,3-DPG
Increased temperature
What can cause the oxygen dissociation curve to shift to the left?
Increased pH
Decreased PaCO2
Decreased 2,3-DPG
Decreased temp
About how much CO2 is dissolved in blood?
10%
About how much CO2 is converted to bicarbonate?
60%
About how much CO2 is bound to Hgb?
30%
What is the Bohr effect?
Decreased PCO2 at the lungs increases Hgb affinity for O2, enhancing the uptake of O2. Increased PCO2 in the tissues causes release of the O2.
What is the Haldene effect?
Increased release of O2 results in increases pick up of CO2
What defines hypoxic hypoxia?
Low PaO2
What defines anemic hypoxia?
Decreased total amount of O2 bound to Hgb
What defines ischemic hypoxia?
Reduced blood flow
What defines histotoxic hypoxia?
Failure of cells to use O2 because of poisoning –> cyanide
