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Stage 2: Inflammation > Dialysis > Flashcards

Flashcards in Dialysis Deck (18)
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1
Q

What are indications for dialysis?

A

1) Hyperkalaemia resistant to medical treatment (insulin dextrose) - can’t get rid of potassium in kidneys
2) Pulmonary oedema/fluid overload resistant to diuretics
3) Symptoms of uraemia (most common reason)
4) Acidosis

2
Q

What are uraemic symptoms (symptoms relating to toxins building up in the body, non specific)?

A

1) Poor appetite
2) Vomiting
3) Weight loss
4) Lethargy and fatigue
5) Itching (build up of phosphate)
6) Malaise

3
Q

What are the goals of dialysis?

A

1) Remove waste products (toxins, potassium)
2) Remove excess water
3) Maintain electrolyte and acid-base balance

4
Q

What are the two types of dialysis?

A

1) Haemodialysis

2) Peritoneal dialysis

5
Q

Describe haemodialysis

A
  • Attached to a machine and blood is removed from the body
  • It is put through a specific filter and then returned back to the body in a clean state
  • The machine makes a fluid which runs in a countercurrent system with the blood across a semi-permeable membrane so need v pure water
  • 3 times a week for 4 hours (what patient will tolerate, not medically best spacing of time)
  • Need a fistula
  • Flow of blood usually 200-300 ml/min
  • Water requirement is 120L per session
6
Q

Where can haemodialysis take place?

A

1) Hospital
2) Satellite unit
3) Home - good bc can do overnight every day instead of coming in 3 times a week however need lots of pure water so need to special plumbing and water supply

7
Q

What do you need to put into the haemodialysis circuit tubing to prevent blood clotting?

A

Heparin

8
Q

Describe the AV fistula

A
  • Connecting vein directly to artery to give blood at a pressure between artery and vein
  • Don’t want vein to collapse
  • Two needles in artery is bad bc continuous puncturing of arteries causes problems with bleeding due to high pressures
  • e.g. radiocephalic, brachiocephalic, brachiobasilic
  • Needs to mature for 4-8 weeks after it is constructed
  • Benefit = all natural, no plastic
9
Q

What are potential complications of AV fistula?

A

1) Blows - blood leaks out of vein when needle goes in (instead of up needle) and moves to surrounding tissue causing bruising
2) Stenoses - narrowings form where joins have been made which can impinge on blood flow and where have lack of blood flow through the fistula it can clot or thrombose

10
Q

Describe use of a graft in haemodialysis

A
  • If a patient doesn’t have good vessels, can put bit of plastic inside (PTFE) which connects a native artery and vein
  • Can be used immediately
  • Same complications
  • Plus risk of infection
11
Q

Describe use of catheters in haemodialysis

A
  • Used if patient doesn’t have weeks to wait and if high levels of toxins so can’t have anaesthetic (needed with graft)
  • Instead dialyse them via a catheter until fistula has matured or graft is safe to do
  • Inserted into big vein e.g. L/R internal jugular or femoral
  • Can be temporary if someone needs emergency dialysis (high K, fluid overload) but after a week move on bc infection risk
  • Use a tunnelled catheter which goes through skin tunnel reducing risk of it falling out and infection risk (gives time to spot it)
  • Have two lumens - one for getting blood out and other for putting it back in
12
Q

Describe the contents of dialysate

A
  • Low in potassium and phosphate (but still need to follow specific diet)
  • Neutral sodium
  • High in bicarbonate
13
Q

Why are dialysis patients usually restricted to 0.5L of fluid a day?

A

To avoid hypotension bc can’t remove more than 2-3L of water a session

14
Q

What are potential complications of dialysis?

A

1) Hypotension bc of fluid removal
2) Septicaemia
3) Bleeding
4) Clotting in fistula and line (can lose fistula)
5) Dialyser reaction - inflammation in blood
6) Air embolus - can mimic PE in lungs

15
Q

Describe peritoneal dialysis

A
  • Home based done by patient
  • Continuous ambulatory peritoneal dialysis
  • Makes use of peritoneal membrane as semi-permeable membrane
  • Creation of an osmotic gradient by addition of an osmotic agent (glucose)
  • Fluid is removed by ultrafiltration caused by the osmotic gradient
  • Solutes are transported by diffusion across a concentration gradient
  • Membrane characteristics vary between patients
  • Need to replace fluid and waste bags
  • Should not be continued for > 5 years
16
Q

What are the benefits of peritoneal dialysis?

A

1) Done by patient at home/work
2) No need to attend hospital/dialysis centre
3) More likely to be able to lead a normal life/travel

17
Q

What are the requirements for peritoneal dialysis?

A

1) Physical → patient has to be able to lift 2kg bags
2) Storage space
3) Hygiene
4) Some residual kidney function

18
Q

What are potential complications of peritoneal dialysis?

A

1) Peritonitis
2) Compliance
3) Leak of fluid outside peritoneal cavity e.g. thoracic cavity, scrotum
4) Inadequate clearance
5) EPS → encapsulating sclerosing peritonitis