ESRD: Dialysis & Transplantation Flashcards
1
Q
Indications for dialysis
A
- general: life-threatening conditions (e.g. severe hyperkalemia, severe volume overload, etc)
- uremic encephalopathy/neuropathy
- pericarditis or pleuritis
- bleeding due to uremia
- fluid overload despite diuretics
- unresponsive HTN
- persitent hyperkalemia, met acidosis, hyper/hypocalcemia or hypophosphatemia unresponsive to therapy
- malnutrition/weight loss
- persisent nausea/vomiting
2
Q
Major types of dialysis
A
- hemodialysis
- peritoneal dialysis
3
Q
Characteristics of hemodialysis
A
- outpatient unit or @ home
- 3x/week
- blood is moved through an extracorporeal circuit via needle or catheter port and enters semi-permeable membrane
- dialysate moves counter-currently on opposite side of membrane
- solutes move into dialysate by diffusion
- blood returned via needle or separate port
- must have access to blood
4
Q
Types of dialysis access
A
- preferred: arteriovenous fistula (AVF) = surgically made artery-vein anastamosis; usually @ arm
- pro: lowest infection rate, last longest
- con: take time to form, may not work
- arteriovenous graft (AVG) = synthetic graft anastamosis
- pro: quicker, more initial success
- con: fail more quickly, more infections
- Dual lumen catheters=@ IJ vein
- pro: can be used immeadiately
- con: highest rate of infection, high rate of dysfxn
5
Q
Conventional dialysis advantages/disadvantages
A
- Advantages:
- rapid, good at removing small mlx
- control fluid removal
- w/health care professionals
- Disadvantages:
- not physiologic, usually remove large volumes
- not good at removing large mlx
- complications
6
Q
Complications of dialysis
A
- infections/sepsis
- hypotension, angina, myocardial ischemia
- disequilibrium syndrome:
- headache
- somnolence
- seizures, coma (rare)
- rare/dangerous:
- air emboli
- anaphylaxis
7
Q
Characteristics of peritoneal dialysis
A
- coiled catheter @ peritoneal cavity w/exit site
- dialysate infused into peritoneal cavity => fluid + solutes move into peritoneal cavity by osmosis => fluid drained and replaced
- continuous ambulatory peritoneal dialysis (CAPD)
- manual exchange of dialysate daily
- continuous cycling peritoneal dialysis (CCPD)
- automatic: noctural cycling by machine
8
Q
Peritoneal dialysis advantages/disadvantages
A
- advantages:
- cheaper
- more freedom, easier to continue job
- gradual, continous fluid removal
- no vascular access
- disadvantages/complications
- hernias
- difficult in large patients
- peritonitis
- additional carb load from dextrose
- catheter problems
9
Q
Kidney Transplant vs. Dialysis
A
- transplant improves patient survival vs. dialysis (not compared to general population)
- more risk/mortality in peri-operative/immediate post-operative period
- significant quality of life improvements + financial benefit (cheaper)
10
Q
HLA characteristics
A
- HLA = products of MHC genes
- Class I HLA antigents = HLA-A, HLA-B, HLA-C
- all nucleated cells
- present cytosolic peptides to CD8+ cytotoxic T cells
- Class II HLA antigens = HLA-DR, HLA-DP, HLA-DQ
- on antigen presenting cells
- present extracellular proteins to CD4+ helper T cells
- Donor HLA antigens will be recognized by recepient as “non-self” => rejection w/out immunosuppresion
11
Q
HLA matching in kidney transplants
A
- 6 HLA matches taken into account
- HLA-A, HLA-B, HLA-DR loci
- matching does not impact actue rejection, but does impact long term graft survival
12
Q
Standard pharmacologic approach to kidney transplantation
A
- calcineurin inhibitor
- proliferation signal inhibitor
- prednisone
13
Q
Clacineurin inhibitors
A
- e.g. cyclosporine and tacrolimus
- inhibits cytokine production/helps prevent graft rejection
- dose: 2x/day w/variations based on transplant timing and immunologic risk
14
Q
Characteristics of proliferation inhibitors
A
- mycophenolate mofetil
- MOA: inhibits purine synthesis
- mTOR inhibitors
- MOA: inhibits mTOR proliferation signlaing
15
Q
Characteristics of prednisone
A
- MOA: multiple, including reduced inflammation
