kidney failure, treatment and urinalysis

Question 1

what are possible causes of kidney failure and what does it mean

Answer 1

-diabetes
-heart disease
-hypertension (persistently high arterial blood pressure)
-infection

-failure of the body to remove excess water and waste products from the blood such as urea and excess salts, rapidly leads to death

Question 2

what can be used to asses kidney function

Answer 2

-estimating GFR (glomerular filtration rate)= measures how much fluid passes into nephrons per minute

-urine analysis e.g proteins in the urine indicate that filtration mechanism has been damaged

Question 3

what are the different treatment options for kidney failure

Answer 3

-renal dialysis (haemodialysis and peritoneal dialysis)
-kidney transplant

Question 4

explain how renal dialysis works

Answer 4

-blood is passed over a partially permeable membrane allowing exchange of substances between the patients blood and dialysis fluid
-dialysis fluid contains the correct concentration of slats, urea, glucose and other substances in blood plasma
-substances in excess in the blood diffuse out into the dialysis fluid, substances found in low concentration in the patients blood will be topped up by diffusion from the dialysis fluid
-patient must also carefully regulate their diet

Question 5

explain haemodialysis

Answer 5

-blood from the artery or vein is passed into the machine
-to stop the blood clotting Heparin is added
-the apparatus includes an air trap and detector to remove air bubbles before the blood is returned to the body
-needed 3 times a week for several hours and is carried out in a clinic or at home

Question 6

explain what happens when blood enters the dialyser in haemodialysis

Answer 6

-blood is pumped in at a higher pressure than dialysis fluid (helps with diffusion)
-dialyser contains fine capillary tubes of dialysis membrane
-blood flows through artificial capillaries while dialysis fluid along the outside in opposite direction = countercurrent system to maintain con grad through out

Question 7

explain the concept of peritoneal dialysis

Answer 7

uses peritoneum as partially permeable membrane with transport proteins in abdominal cavity, the dialysis fluid is drained in and out

Question 8

explain kidney transplant and what is needed for it to occur

Answer 8

-one functional donated kidney will restore a patients health
-donor and recipinet must have closely matched tissue type and blood group to prevent rejection
-patient must take immunosuppressant drugs for the rest of their life to prevent organ rejection
-harvested donor kidney must be transplanted within 48h of removal

Question 9

compare dialysis vs kidney transplant

Answer 9

dialysis:
-patient must be carefully monitoring their diet
-expensive in longterm
-haemodialysis and PD are readily available
-no drugs are required
-patient must undergo dialysis several times a week for the rest of life

transplant:
-patient can eat normally
-expensive in short term
-kidney must be carefully matched and there are long waiting lists
-patients must take immunosuppressant drugs forever
-kidney transplant patients are cured

Question 10

what are the advantages and disadvantages of kidney transplant

Answer 10

advantages:
-no longer need dialysis
-fell better
-able to travel and lead a normal life without restrictions of dialysis
-diet less limited
-no longer perceived as ill

disadvantages:
-immunosuppressant drugs for life
-major surgery under general anasthetic
-risk of infection/ bleeding/ damage to other organs during surgery
-frequent monitoring for signs of organ rejection
-side effects from immunosuppressants e.g increased chance of infection, fluid retention, high blood pressure

Question 11

what are the characteristics of healthy urine

Answer 11

-pH 6 (4.5-8)
-pale to dark yellow or amber
-normal urine volume 750-2000ml / 24h
-no glucose, excessive cellular material or protein in urine are possible signs of infection or kidney failure

Question 12

explain how urine analysis can be used to test for pregnancy using monoclonal antibodies

Answer 12

1. urine poured onto test stick
2. hCG binds to mobile monoclonal antibodies attached to a blue head
3. mobile antibodies move down the stick
4. if hCG is present, it binds to fixed antibodies holding bead in place= blue line forms
5. mobile antibodies with no hCG attached bind to another fixed site to show the test is working (control)

Question 13

how are anabolic steroids tested and what for

Answer 13

-increase protein synthesis and are banned in competitive sports

-detected in urine using gas chromatography or mass spectrometry