Delivery of Oxygen | Hemodynamics (Part 2) Flashcards
What is the primary goal of hemodynamics?
Delivery of oxygen and nutrients to tissues
What secondary function does hemodynamics serve?
Removal of waste products from metabolism
What is the equation for oxygen delivery (DO2)?
DO2 = Cardiac Output * Concentration of Oxygen in Arteries * 10
Why is the factor of 10 used in the oxygen delivery equation?
To align the units of cardiac output and concentration of oxygen
What does cardiac output represent in the oxygen delivery equation?
The amount of blood circulating through the body
What does concentration of arterial oxygen represent?
How concentrated the oxygen is in the blood
What are the three factors determining the concentration of arterial oxygen (CaO2)?
- Hemoglobin
- Oxygen saturation
- Partial pressure of oxygen
Which factors have a larger impact on the concentration of arterial oxygen?
- Hemoglobin
- Oxygen saturation
What is the equation for concentration of arterial oxygen (CaO2)?
CaO2 = (Hemoglobin * 1.39 * Arterial Oxygen Saturation) + (Partial Pressure of Arterial Oxygen * 0.003)
What is the equation for cardiac output?
Cardiac Output = Heart Rate * Stroke Volume
What does stroke volume represent?
The amount of blood ejected with each beat
In what units is cardiac output measured?
Liters per minute
What is the normal range for stroke volume?
60-120 milliliters per beat
What is the normal range for heart rate?
60-100 beats per minute
What is the normal range for cardiac output?
4-8 liters per minute
Why is cardiac index used instead of cardiac output in some cases?
It accounts for patient size
What two factors does cardiac index use?
- Cardiac output
- Body surface area
What is the normal range for cardiac index?
2.5 to 4 liters per minute per meter squared
What are the three factors that determine stroke volume?
- Preload
- Contractility
- Afterload
