Kidney Failure

Question 1

What is the glomerular filtration rate (GFR)?

Answer 1

The rate at which fluid enters the nephrons.

Question 2

What are monoclonal antibodies?

Answer 2

Antibodies made from one type of cell - they are specific to one complementary molecule.

Question 3

What is renal dialysis?

Answer 3

A mechanism used to artificially regulate the concentration the concentration of solutes in the body.

Question 4

What can kidney failure be caused by?

Answer 4

It can be caused by diabetes mellitus (type 1 and type2), heart disease, hypertension and infection.

Question 5

What happens if the kidneys fail completely?

Answer 5

They are unable to regulate the levels of water and electrolytes in the body or to remove waste products such as urea from the blood.

Question 6

What are electrolytes?

Answer 6

Substances that form charged particles in water

Question 7

How is kidney function assessed?

Answer 7

Can be assessed by estimating the GFR and by analysing the urine for substances such as proteins. Proteins in the urine indicate the filtration mechanism has been damaged.

Question 8

What is a normal/abnormal reading of the GFR?

Answer 8

Normal = 90-120cm3/min-1

Abnormal = anything less than 60cm3/min-1

Question 9

What figure of GFR indicates kidney failure?

Answer 9

15cm3/min-1

Question 10

What is the first step of renal dialysis?

Answer 10

Waste products, excess fluid, and mineral ions are removed from the blood by passing it over a partially permeable dialysis membrane that allows the exchange of substances between the blood and the dialysis fluid.

Question 11

What does the dialysis fluid contain?

Answer 11

The correct concentrations of mineral ions, urea, water and other substances found in the blood plasma.

Question 12

What diffuses at the membrane into the dialysis fluid?

Answer 12

Any substances in excess in the blood.

Question 13

What are the two different types of renal dialysis?

Answer 13

Haemodialysis

Peritoneal dialysis

Question 14

What is haemodialysis?

Answer 14

Blood from an artery/ vein is passed into a machine that contain many artificial capillaries to increase the surface area. The artificial capillaries are surrounded by dialysis fluid which flows in the opposite direction (a countercurrent system) - this improves the efficiency of the exchange.

Question 15

Why is heparin added in haemodialysis?

Answer 15

To avoid clotting

Question 16

Where is haemodialysis usually performed?

Answer 16

In a clinic two or three times a week for several hours at each session. Some patients learn to carry it out at home.

Question 17

Describe peritoneal dialysis.

Answer 17

The dialysis membrane is the body’s own abdominal membrane (peritoneum). A surgeon implants a permanent tube in the abdomen. Dialysis solution is poured through the tube and fills the space between the abdominal wall and the organs. After several hours, the solution is drained from the abdomen.

Question 18

Where can PD (peritoneal dialysis) be carried out?

Answer 18

Can be carried out at home or at work. The patient can walk around while having dialysis, the method is sometimes called ambulatory PD.

Question 19

What must dialysis be combined with to ensure healthy kidneys?

Answer 19

A carefully monitored diet.

Question 20

How does a kidney transplant occur?

Answer 20

Patient is under anaesthesia.
Surgeon implants the new organ into the lower abdomen and attaches it to the blood supply and the bladder.
Patients are given immunosuppressant drugs to prevent rejection of the new organ.

Question 21

What are the advantages of a kidney transplant?

Answer 21

Freedom from time consuming renal dialysis.
Feeling physically fitter
Improved quality of life - able to travel
Improved self-image - no longer have a feeling of being chronically ill.

Question 22

What are the disadvantages of a kidney transplant?

Answer 22

Need to take immunosuppressant drugs
Need for major surgery under general anaesthetic
Need for regular checks for signs of rejection
Side effects off immunosuppressant drugs - fluid retention, high blood pressure, susceptibility to infections.

Question 23

Give reasons for urine testing.

Answer 23

Glucose in the diagnosis of diabetes
Alcohol to determine blood alcohol levels in drivers
To test for recreational drugs
Human chorionic gonadotropin (hCG) in pregnancy test
Anabolic steroids, to detect improper use in sporting comps.

Question 24

What must the relative molecular mass be less than for it to be tested through urine analysis?

Answer 24

69,000

Question 25

What are the five steps to how pregnancy testing is done?

Answer 25

1) Urine poured onto a test stick
2) hCG binds to mobile antibodies attached to a blue bead
3) Mobile antibodies move down test stick
4) If hCG is present, it binds to fixed antibodies holding the bead in place - a blue line forms
5) Mobile antibodies with no hCG attached bind to another fixed site to show the test is working

Question 26

How can anabolic steroids be tested for?

Answer 26

Through taking a urine sample and doing a test called gas chromatography.