Hemodialysis

DIALYSIS THERAPY

DIALYSISMEANING Is a movement of

fluid and molecules across a semipermeable membrane from one compartment to another.

PURPOSE /USE/GOALS OF DIALYSIS THERAPY

To correct fluid and electrolyte imbalances and to remove waste products of protein metabolism.

To correct acidosis and replenish the bicarbonate levels in blood.

To treat drug overdoses To control uremia and to physically prepare

the patient to revive a transplanted kidney.

PRINCIPLES OF DIALYSIS Solutes and water move across

the semipermeable membrane from the blood to the dialysate or from the dialysate to the blood according to the concentration gradient.

THREE PRINCIPLES1. Diffusion

Is the movement of solute from an area of higher concentration to the area of lower concentration.

2. Osmosis Is the movement of fluid from an

area of lower concentration to an area of higher concentration of solutes.

3. Ultrafiltration Results when there is an osmotic gradient or pressure gradient across the membrane.

In peritoneal dialysis excess fluid is removed by increasing the osmolality of the dialysate with the addition of glucose.

In hemodialysis the gradient is created by increasing pressure in the blood compartment (positive pressure) or decreasing pressure in the dialysate compartment (negative pressure).

HAEMODIALYSIS MEANING Is movement substances from

blood through a semi permeable membrane and into a dialysis solution (dialysate –bath) (synethetic membrane).

Is a procedure in which patient’s toxin laden blood is diverted in to a dialyser, cleaned and then returned to the patient.

VASCULAR ACCESS

• Types of vascular access

1. Shunts, (telfon, external)

2. Internal Arteriovenous fistulas

3. Internal Arteriovenous grafts (AV)

4. Temporary vascular access

Dialyzer

Dialysis procedure

Dialysis procedure

COMPLICATIONS OF HAEMODIALYSIS

HypotensionMuscle CrampsLoss of BloodHepatitisSepsisDisequilibrium Syndrome