Blood as a Fluid 1 Flashcards
How is flow rate calculated?
Q = delta(P)/R
What is Pascal’s Principle?
If external pressure is applied to confined fluid, pressure at all points of the fluid increase by amount applied
How is hydrostatic pressure calculated?
P = density * gravity * distance below surface
What is the requirement for flow to occur?
A positive change in pressure
How is pressure calculated?
P = F/A
Why is an IV drip bag elevated?
It relies on hydrostatic pressure for the fluid to flow into the patient’s body
Why doesn’t atmospheric pressure (101.3 kPa) crush you?
The internal body pressure acting outwards at a similar magnitude
How does a pressure gauge work?
It measures the difference between pressure inside a vessel and atmospheric pressure
Example: Pressure gauge measure mean blood pressure at 13 kPa, meaning that is it 13 kPa higher than the atmospheric pressure
What is systolic pressure?
The highest pressure at which blood can flow at all (maximum pressure)
What is diastolic pressure?
The highest pressure at which blood flows at a steady rate (minimum pressure)
