Dialysis- Final Exam Flashcards
Dialysis
filtering metabolic waste products from blood; separation of dissolved substances from a solution by allowing the solution to diffuse through a semipermeable membrane
Hemodialysis
Removing waste products such as creatinine and urea, as well as free water from the blood when the kidneys are in renal failure
Peritoneal Dialysis (PD)
a Tx for patients with severe chronic kidney disease; uses patient’s peritoneum as a membrane across which fluids and dissolved substances are exchanged
What substances are exchanged with peritoneal dialysis?
Electrolytes, urea, glucose, albumin and other small molcules
Continuous Ambulatory Peritoneal Dialysis (CAPD)
Fluid is introduced through a tube in the abdomen and flushed out either every night while the patient sleeps or via regular exchanges throughout the day
What is used as an alternative to hemodialysis, especially in kids?
Peritoneal dialysis (PD)
Dialysate solution
dialysis solution in the dialyzer helps remove wastes/fluid from blood.
Dialyzer
artificial kidney filter designed to provide controllable transfer of solutes and water across a semi-permeable membrane separating flowing blood and dialysate streams
What does a dialysate solution contain?
Chemicals in concentrations similar to blood, a mixture of purified water and measured chemicals, which flows countercurrent on the outside.
What substances that must remain in the blood stream?
Glucose sodium calcium magnesium
Substances that must remain the in blood stream are in what concentrations in the dialysate solution?
Concentrations similar to blood
What does the composition of dialysate determine?
Which solutes pass out of and which stay in teh blood during dialysis
What transfer processes occur in a dialyzer?
Diffusion (dialysis) and convection (ultrafiltration)
What are the three basic dialyzer designs?
Coil, parallel plate, hollow fiber configurations
What is one of the major modes of mass transfer?
Convection (diffusion is another; diffusive transport)
What type of kidney failure do we create on bypass?
Acute renal failure
Acute renal failure (ARF)
A sudden loss of kidney function caused by an illness, an injury, or a toxin that stresses the kidneys (kidney function may recover)
Chronic Kidney Disease (CKD)
A long and usually slow process where the kidneys lose their ability to function
Why type of kidney failure will you get with stenosis in the renal artery?
CKD
End-stage renal disease (ESRD)
When the kidneys have completely and permanently shut down
Would we give mannitol for ESRD?
no because it’s cleared in the kidneys
Renal failure defintiion
decrease in GFR
How is renal failure detected biochemically?
Elevated serum creatinine level
How do we characterize ARF?
- Rapid loss of kidney function (hypovolemia)
- Causes include low blood volume
- Exposure to harmful substances
- Obstruction of urinary tract
What lab findings help us diagnose acute kidney injury?
Elevated blood urea nitrogen level (BUN)
Elevated creatinine
Inability of the kidneys to produce sufficient amounts of urine
What are some complications of ARF?
Metabolic acidosis High K+ levels Uremia Changes in body fluid balance (big shift) Effects to other organ systems
How is chronic kidney disease identified?
Significantly elevated creatinine
What do higher levels of creatinine indicate?
Falling GFR; and as a result decreased capability of the kidneys to excrete waste products
What are creatinine levels in early stages of chronic kidney disease?
may be normal
Problems frequently encountered in kidney malfunction
- Abnormal fluid levels in body
- deranged acid levels
- Abnormal potassium, calcium, phosphate
- anemia
- hematuria (blood loss in urine)
- proteinuria (protein loss in urine)
Long-term kidneys problems have significant repercussions on other diseases such as what?
Cardiovascular disease
Ultrafilters/ Hemoconcentrators
Removed total body water on the principle of hydrostatic pressure gradients
What is used to treat renal failure?
Dialysis; removal of diffusable solutes based on the principle of concentration gradient and solute drag established by dialysate solution