Dialysis and Transplantation Flashcards
Which toxins can dialysis remove that build up in end-stage kidney disease?
Urea
Potassium
Sodium
Creatinine
Which ion can be infused using dialysis?
Bicarbonate
List the components of dialysate
Pure water Sodium Bicarbonate Potassium Glucose
How is water removed from the body in dialysis?
Create negative pressure across membrane to suck water out (filtration)
Dialysis is very efficient. True/False?
False
Not very efficient; longer treatment equals better efficiency
What is the time schedule for haemodialysis?
4 hours, 3 times a week
How much fluid, salt, potassium and phosphate is allowed during dialysis?
1 litre water a day
Low salt diet
Low potassium diet
Low phosphate diet
What is the gold standard for dialysis access?
Arteriovenous fistula, usually in arm
What are the drawbacks of an AV fistula?
Requires maturation of 3-6 months before use
Can limit blood flow to distal arm
What is the alternative access for dialysis whilst the AV fistula is maturing?
Tunnelled venous catheter inserted into jugular/subclavian/femoral vein
What are the drawbacks of tunnelled venous catheters?
High risk of infection
Damage vein
What can go wrong with dialysis?
Fluid overload/oedema
Blood leaks
Hypokalaemia - cardiac arrest
What is the alternative to haemodialysis and how does it work?
Peritoneal dialysis
Use peritoneal membrane for diffusion of entering dialysate fluid in abdomen, which drains into bag afterwards
What is the time schedule for peritoneal dialysis?
4 times a day
OR
Overnight (1 bag a day)
What is the advantage of peritoneal dialysis over haemodialysis?
Portable - less restrictive
What are the disadvantages of peritoneal dialysis?
Infection - peritonitis
Membrane failure
Hernias
When is dialysis started based on bloods?
Resistant hyperkalaemia
GFR less than 5 (following preparation!)
Unresponsive acidosis
Which syndrome can result in the short-term following haemodialysis?
Disequilibrium syndrome involving cerebral oedema and seizures
In end-stage kidney disease, survival with dialysis decreases with increasing age. True/False?
True
Kidney is taken out in transplant. True/False?
False
Leave kidneys and put new kidney in lower iliac fossa/pelvis
Which donor blood groups are compatible with recipient with blood group O?
O
Which donor blood groups are compatible with recipient with blood group A?
O
A
Which donor blood groups are compatible with recipient with blood group B?
O
B
Which donor blood groups are compatible with recipient with blood group AB?
O
AB
People with blood group O have which antibodies? What is the effect of this?
Anti-A and anti-B antibodies, so can only receive donor from person with blood group O
What are HLA proteins? List the main types
Cell surface proteins that activate the immune system in graft rejection
HLA A, B and DR
Which HLA are class 1?
HLA A
HLA B
Which HLA are class 2?
HLA DR
1 HLA is inherited from each parent. True/False?
True
A patient who has been exposed to non-self HLA Ag forms antibody to it and this leads to rejection. What are the main ways HLA Ag exposure can occur?
Blood transfusion
Pregnancy
Previous transplants
Outline the process of graft rejection
HLA antigen binds to dendritic cell which expresses MHCII that activates CD4 cells, which enable B cell proliferation (produce antibodies to graft) and CD8/NK production which directly attack graft
Describe the 3 forms of graft rejection
Hyperacute: preformed Ab to transplant, minutes
Acute: T/B-cell mediated, early on
Chronic: immune/vascular deterioration of transplant
Acute graft rejection may be treatable with immunosuppression. List some medication
Steroids
MMF
Cyclosporin
Tacrolimus
Which class of drug includes cyclosporin and tacrolimus? How do they work?
Calcineurin inhibors
Inhibit activation of CD4 cells (thus reduce NK/CD8/B-cell proliferation)
List some side effects of calcineurin inhibitors
Renal dysfunction Hypertension Diabetes Tremors Drug interactions
How do azathioprine and mycophenolate help in immunosuppression?
Block purine synthesis - suppress proliferation of B and T cells
Can cause oversuppression
Which drug does azathioprine notably, infamously, dangerously interact with?
Allopurinol
List the main types of donor kidney
Brain dead patient
Cardiac dead patient
Live donor (familial)
Kidney-pancreas dual transplant (diabetics)
Allocation of kidneys in UK is based on tissue typing and then time on donor list. True/False?
True
List absolute contraindications to transplantation of kidney
Malignancy Untreated TB Severe IHD (not treatable) Severe airway disease Active vasculitis Severe PVD
