Explain the Principle of Dialysis Flashcards

Removing wastes from the blood Removes excess fluid from the blood Keeping electrolytes in balance

A mixture of a solvent and a solute

Fluid

Any substance that can be dissolved into the solvent

The solution that is used during dialysis Solvent: Water Solute: Electrolytes (potassium, calcium, sodium, magnesium, and chloride ions) and glucose

Closely match the levels in the human blood. This reduced the loss of these electrolytes out of the blood and into the dialysate during dialysis.

Can be controlled by changing the dialysate. Adding an electrolyte to the dialysate at a level higher than in the blood will allow the electrolyte to enter the pts blood during a treatment.

A type of thin, flexible filter- a barrier that allows only particles smaller than a certain size to pass through it.

In dialysis, the semipermeable membrane's holes allow small molecules, such as water and urea, to pass through easily. Middle molecules can also pass through, but more slowly. The small size of the pores keeps larger molecules and blood cells from passing through the membrane.

The process by which atoms, molecules, and/or other particles move from an area where they are in high concentration to an area where they are in low concentration.

Energy for the movement comes from the molecules themselves, and does not depend on outside forces.

Concentration Gradients Molecular weight of the solutes Temperature

Solutes move through a semipermeable membrane from an area of greater concentration to an area of lesser concentration. Solutes can move through a membrane in either direction, but always toward the area of lesser concentration. As the difference in solute concentration increases, solute movement increases to. Diffusion stops when the concentrations on both sides of the membrane are equal.

Smaller molecules diffuse more easily and quickly than larger ones. Large blood components such as RBC, WBC, albumin, and platelets diffuse more slowly because they are bigger. Small molecules, such as urea and salts, diffuse faster. Middle molecules may pass through, but more slowly.

Molecules move faster at higher temperatures, so warmer fluids allow faster diffusion. Dialysate temperature is controlled during dialysis for pt safety, comfort and faster diffusion.