Haemodynamics Flashcards
What does blood separate out into when centrifuged WITH anticoagulent
Plasma, buffy coat, rbcs
What is the name of the layer that forms when blood is centrifuged without anti coagulent and what is the difference?
Serum instead of plasma
Serum is plasma but without the clotting factors. The clotting factors have been used to coagulate the blood
What’s the most common cause of an increase in blood viscosity?
Multiple Myeloma- a cancer of the plasma cells where you get an increase in number, resulting in the increase in blood viscosity
Define Flow and Pressure
Flow- the volume of fluid passing a point per unit time
Pressure- The Force exerted on the walls of the blood vessels per unit area
Whats the difference between laminar and turbulent flow, and when can turbulent flow occur? (4)
Laminar flow is flow in one direction (ie in a straight line)
Turbulent flow is when the flow of blood is in multiple directions.
Turbulent flow can take place
After passing an obstruction in the vessel
When the flow of blood becomes too great
When blood makes a sharp turn
With increased resistance in the resistance vessels
What happens to the pressure after a stenosis
Increases. Results in post stenotic dilation
What’s the name given to the sound heard with turbulent blood flow
Bruit
What is in the buffy coat
Contains the most WBCs and platelets
What are the consequences of an increase in blood viscosity?
You get sludging–>Decreased flow in the peripheries–>Decreased concentration gradient–>Less oxygen diffusion into tissue–>cell death
You see a minor change in the whole blood viscosity. What could be the cause?
Inflammation. You would get an increase in C-reactive proteins, Acute phase proteins etcs.. that can increase the visocity (Minorly)
Label the aortic pressure tracing and explain the blood velocity graph
See word doc
Session 1- Capillaries, Pericardium, Surface Anatomy, Haemodynamics
Final page
What determines the strength of a pulse
Pulse pressure
Strength of ventricular contraction
Name 3 reasons for a weak pulse
Hypovolaemia, Left ventricular heart failure, Aortic valve stenosis
Name 2 reasons (explained) for a bounding pulse
Bradycardia–>Increased time for diastolic run off–>Decreased end diastolic pressure–>Increased pulse pressure
Low peripheral resistance–>Blood emptying faster–>Sharper diastolic run off–>Lower end diastolic pressure–>Increased pulse pressure
Pulse Pressure=?
Pulse pressure=Peak systolic pressure-End diatolic pressure
Mean aterial pressure=
End diatolic pressure + 1/3 pulse pressure
