Flashcards in F214:02:08 Kidney Failure Deck (57):
What is dialysis?
the use of a partially permeable membrane to filter the blood
What is the dialysis membrane?
the partially permeable membrane that separates the dialysis fluid from the patients blood in a dialysis machine
What is dialysis fluid?
a complex solution that matches the composition of body fluids
What is haemodialysis?
Where blood is taken from the vein, passed through a dialysis machine so that exchange can occur across an artifically partially permeable membrane
What is peritoneal dialysis?
where dialysis fluid is pumped into the body cavity so that exchange can occur across the peritonial membrane
What are the three most common causes of kidney failure?
What is diabetes mellitus?
both type 1 and type II sugar diabetes
What happens to the body once complete kidney failure has occured?
the body is unable to remove excess water and certain waste products from the blood (salts and urea)
It is therefore unable to regulate the levels of water and salts in the body
So this rapidly leads to death.
What are the two main types of treatment for kidney failure?
dialysis and transplant
What is the most common treatment for kidney failure?
What does dialysis actually do?
removes wastes, excess fluid and salt from the blood by passing the blood over a dialysis machine
What does dialysis fluid contain?
the correct concentrations of salts, urea, water and other substances in blood plasma
Why is it important that dialysis fluid contained the correct concentration of substances for blood plasma?
So that any substances that are of excess in the blood can diffuse across the membrane into the dialysis fluid
And any substances that are too low in the blood diffuse into the blood from the dialysis fluid
What must dialysis be combined with?
a carefully monitored diet
What kind of blood is passed from the vein into the membrane that contains the artificial dialysis membrane?
What is added to the dialysis membrane to avoid clotting ?
What is it important to remove from the blood before it reenters the body after dialysis?
any bubbles that have formed in the machine
How often is haemodialysis usually performed
3 times a week
How long does haemodialysis usually take?
What is the key difference of peritoneal dialysis compared to normal dialysis'?
The filter is the bodys own abdominal membrane
What is the name of the bodys abdominal membrane
How is peritoneal dialysis carried out?
The surgeon implants a permanent tube into the abdomen and dialysis solution is poured through the tube and fills the space between the abdominal walls and organs
When is PD usually performed?
in several consecutive sessions daily
Why is PD sometimes known as ambulatory PD?
as you can walk around while it is being carried out
What happens to the old kidneys when someone has a transplant?
They are left in place unless they are likely to cause infection or are cancerous
Where can donor kidneys come from?
a living relative who is willing to donate one of their healthy kidneys or from someone who has died
Describe a kidney transplant
- major surgery
- patient goes under anaesthesia
- surgeon implants the new organ into the lower abdomen and attaches it to the blood supply and the bladder
How long does it take for the patent of a kidney transplant to feel better?
immediately feel better
What is the best life-extending treatment for kidney failure?
a kidney transplant
What can sometimes happen as a negative side effect to kidney failure?
The body will recognise the organ as a foreign object and may reject it so produce a reaction
What are patients given after a kidney transplant to prevent rejection?
Name 5 advantages of a kidney transplant
1. freedom from time consuming dialysis
2. diet is less limited
3. feeling physically better
4. a better quality of life (eg able to travel)
5. No longer seeing oneself as chronically ill
Name 5 disadvantages of a kidney transplant
1. Need immunosuppressants for the life of the kidney
2. Need major surgery under a general anaesthetic
3. There are risks of surgery
4. You have to have frequent checks for organ rejection
5. There can be many side effects
Give some examples of risks of a kidney transplant (in terms of surgery).
damage to surrounding organs
Give some examples of potential side effects of a kidney transplant
anti-rejection medicines may cause fluid retention and high blood pressure
immunosuppressants increase suspectibility to infection
What is the largest molecular mass a substance/molecule can have to enter the nephron?
What is human chrorionic gonadotrophin (hCG)
a hormone released by human embryos
Its presence in the mothers urine confirms pregnancy
What are anaebolic steroids?
drugs that mimic the action of steroid hormones that increase muscle growth
What is gas chromatography?
a technique used to separate substances in the gaseous state
What is a chromatogram?
a chart produced when substances are separated by movement of a solvent along a permeable material such as paper or gel
What does an embryo starts secreting when it has been implanted in the lining of the uterus?
a pregnancy hormone known as human chronic gonatrophin
Describe human chorionic gonadotrophin
relatively small glycoprotein with a molecular mass of 36700
Is found in urine as early as 6 days after conception
What is the molecular size of hCG?
what does hCG stand for?
human chorionic gonadotrophin
How do pregancy tests work?
they are manufactured with monoclonal antibodies, which are specific so only bind to hCG
any hCG-antibody complexes move up the strip until it sticks to a band of immobilised antibodies
meaning any antibodies carrying a blue bead and attached to hCG are held in one place forming a blue line
Why do you not use the first blue line as an indication for pregnancy ona pregnancy test?
As this line is used as a comparison and is always there
What do anaebolic steroids do?
increase protein synthesis within cells
What is the result of using anaebolic steroids?
the build up of cell tissue, particularly muscle
Why are non-medical anaebolic steroids controversial?
As in competitive sport, they can give those who take it an advantage
- they can have dangerous side effects
What is the half life of anaebolic steroids?
about 16 hours
How long do anaebolic steroids remain in the blood?
Why is testing for anaebolic steroids quite simple?
As they are relatively small molecules so can enter the nephron easily
so can be tested in the urine
How do you test for anaebolic steroids?
you analyse a urine sample in a lab using gas chromatography or mass spectrometry
Describe gas chromatography
The urine sample is vaporised in the presence of a gaseous solvent
Passes down a long tube lined with absorption agent
Each substance dissolves differently in the gas and stays there for a unique, specific retention time
Eventually the substance comes out of the gas and is absorbed into the lining
This is then analysed to create a chromatogram
What components of the diet must be carefully monitored in someone who undergoes dialysis?
Explain why haemodialysis fluid has to be sterile and at 37 degrees C
So that it doesnt cause infection to the recipient, as it has a good medium for microorganisms
Kept at 37 degrees so that it is the temp of the body to prevent hypothermia or hyperthermia