Flashcards in Ultrafiltration- Final Exam Deck (94)
What is hemoconcentration?
Increase in the number of red blood cells resulting from a decrease in plasma volume
What does hemoconcentration increase?
Why is it important to know if it's whole blood or PRBCs?
Whole blood has normal HCT.
Conventional Ultrafiltration (CUF)
removes plasma water and low molecular weight solutes by a convective process using hydrostatic pressure forces across a semipermeable membrane
Zero Balance Ultrafiltration (ZBUF)
technique utilizing a hemoconcentrator to maintain a controlled equalized input and output over the CPB pump run
Slow Continuous Ultrafiltration (SCUF)
technique utilizing a slow, steady ultrafiltration during the CPB pump run; slow rate over time
Modified Ultrafiltration (MUF)
ultrafiltration occuring after the separation from CPB
When were the first concepts related to the use of ultrafiltration in hospital practice?
Where do modern hospitals incorporate ultrafiltration?
In many areas of surgical and medical therapy
What are two areas constantly requiring ultrafiltration as a significant part of their respective protocols of patient's management?
Medicine and surgery
What does ultrafiltration allow?
filtration of body water across a semi-permeable membrane utilizing a hydrostatic pressure gradient
What are 4 hemoconcentrator companies?
Where is the blood flow path in a hemoconcentrator?
Inside the hollow fibers
Where is the effluent path in a hemoconcentator?
Outside the hollow fibers
How does water get to the effluent side in a hemoconcentrator?
Letting the pressure gradient "pushes" body water to the effluent side (can be used with or without vacuum)
What does dialysis use?
Dialysate solution on the effluent side to control precise solute excretion
exchange of things dissolved in fluid (solutes) across a membrane due to differences in amount of the solutes on the two sides (concentration gradient)
What will happen if a higher concentration of a given solute is on one side?
Diffusion will try to make the concentrations the same on both sides
What else is ultrafiltration referred to as?
What is ultrafiltration?
Fluid flow through the membrane, forced by a difference in pressure on two sides of the membrane
net movement of water across a selectively permeable membrane
What drives osmosis?
Difference in the amounts of solute on the two sides of the membrane
What does osmosis refer to in dialysis?
Water movement across cell membranes (not across hemodialyzer membrane)
Achieving filtration across a membrane requires __________ and ____________.
Blood flow; hydrostatic pressure gradient
The ability of a solute to be filtered through the membrane depends on what?
The molecular weight compared to the pore size of the filter (sieving coefficient)
The rate of solute removal through the membrane depends on ________ and ___________.
Flow rate; transmembrane pressure (TMP)
What is pore size measured in?
Where are pore size and transmembrane pressure (TMP) limites noted?
What does a dalton quantitate?