15.8 Kidney failure Flashcards
What are kidney problems caused by high blood pressure?
Protein in the urine
Blood in the urine
How does protein get into the urine?
High blood pressure
Basement membrane or podocytes of Bowman’s capsule damaged
No longer act as filters
Large plasma membranes pass into FILTRATE then into urine
What does blood in the urine show?
Symptom of filtering process not working properly
What happens if the kidneys fail COMPLETELY?
Urea and mineral ion concentration in body builds up
What are effects of the kidneys failing completely?
LEB
TUB (Heartbeat sound)
HBP
WB
PSJ
A
(Welcome Back, Princess Sarah-Jane Anne!)
Loss of electrolyte balance
Toxic urea build-up in blood
High blood pressure
Weakened bones
Pain and stiffness in joints
Anemia
How does kidney failure lead to loss of electrolyte balance?
Kidney failure
Body cannot EXCRETE sodium, potassium and chloride ions
Osmotic imbalances in tissues
Eventual death
How is build-up of toxic urea in the blood an effect kidney failure?
Body cannot get rid of urea
Poison cells
How do the kidneys control blood pressure?
Maintain water balance of blood
What can high blood pressure CAUSED BY kidney failure do?
Blood pressure increases
Heart problems and strokes
How does kidney failure cause bones to weaken?
Calcium/phosphorus balance in blood is lost
Why does kidney failure cause pain and stiffness in the joints?
Abnormal proteins build up in blood
What hormone does the kidneys produce?
Erythropoietin
What is the function of erythropoietin?
Stimulates formation of red blood cells
How does kidney failure cause anaemia?
Less erythropoietin produced
Less red blood cells formed
Tiredness and lethargy
What is GFR?
Glomerular filtration rate
What is the glomerular filtration rate?
Rate at which blood is filtered in Bowman’s capsule of the nephrons
What is GFR used for?
A measure to indicate kidney disease
What is eGFR?
Estimated glomerular filtration rate
What is creatinine?
Breakdown product of muscles
What does measuring the level of creatinine in the blood give?
eGFR
What are the units for eGFR?
cm3/min
What shows the kidneys are not working properly?
Level of creatinine in blood GOES UP
What factors need to be taken into account when calculating the GFR?
GFR decreases steadily with age even in healthy people
Men have more muscle mass and more creatinine
What are he thresholds for GFR?
70 normal
60 for 3 months shows moderate / severe CHRONIC kidney disease
Below 15 kidney failure
What are the two main ways kidney failure is treated?
Renal dialysis
Transplant
What happens in renal dialysis?
Function of kidneys carried out artificially
What are the two main types of dialysis?
Haemodialysis and peritoneal dialysis
What happens to blood in a dialysis machine?
Blood enters dialysis machine from patient’s ARTERY
Flows between partially permeable dialysis membranes
What do the partially permeable dialysis membranes mimic?
Basement membrane of Bowman’s capsule
What is special about the concentrations of the dialysis fluid?
Normal plasma levels of glucose so no net movement out of blood
Normal plasma levels of mineral ions so excess diffuses into dialysis fluid
Restores electrolyte balance of blood
No urea
Steep concentration gradient
Most urea leaves the blood
How is EXCHANGE maximised in a dialysis machine?
Blood and dialysis fluid flow in opposite directions
Maintains countercurrent exchange system
Exchange maximised
What process allows substances to move between the dialysis fluid and the blood?
Diffusion down concentration gradient
What are the disadvantages of haemodialsysis?
DFTW
Don’t Forget To Work!
Diet, Fluid, Time, Weekly
Manage diets carefully
E.g. eat little protein and salt
Monitor fluid intake
Eight hours process
Several times a week
What is peritoneal dialysis?
Dialysis done inside body using peritoneum
What is the peritoneum?
Lining of abdomen
How long is the dialysis fluid left in the peritoneal membranes for?
Several hours
