S-shaped saturation curve Hematology

What measurement is on the y-axis on the s-shaped hemoglobin dissociation curve?

% saturation of hemoglobin

What measurement is on the x-axis on the s-shaped hemoglobin dissociation curve?

partial pressure of oxygen (mmHg)

In normal conditions, what is the partial pressure of oxygen in the lungs and systemic arterial blood?

Around 104 mmHg

In normal conditions, what is the partial pressure of oxygen in tissues (or resting point)?

Around 40 mmHg

When you take the % saturation of hemoglobin at the lungs minis the % saturation of hemoglobin at tissues, what does difference of the two tell you?

The % of oxygen unloaded to tissues

What type of activity of the body results in low pressure of oxygen (high amount of oxygen inhaled) ?

Exercise

More oxygen being unloaded to tissues results in what type of shift?

right shift

What are the conditions in the blood that can cause a right shift? (5)

- high protons

- high CO2

- High 2,3 DPG

- high temperature

- increased oxygen dissociation

If there is a right shift how does this affect hemoglobin affinity for oxygen? why?

it decreases. higher amounts of oxygen leaving hemoglobins to go to tissues (they don't want to hang onto them)

Less oxygen being unloaded to tissues results in what type of shift?

left shift

What are conditions in the blood that can cause a left shift? (5)

- decreased protons

- decreased 2,3 DPG

- decreased temperature

- decreased CO2

- decreased oxygen dissociation

If there is a left shift how does this affect hemoglobins affinity for oxygen? why?

high affinity. There is more oxygen available, so tissues don't need it as readily so hemoglobin wants to hang on to oxygen

When pO2 is <20mm, what is hemoglobin's affinity for oxygen? Why?

- low affinity

- since the pressure of oxygen is lower the oxygen wants to be released in tissues

When pO2 is > 60mmHg, what is hemoglobin's affinity for oxygen? Why?

- high affinity

- since pressure of oxygen is higher, it forces more oxygen to bind to hemoglobin