Renal Replacement Therapy - Dialysis Flashcards
What is ESRD?
End stage renal disease = irreversible damage to a persons kidney’s so severe that to maintain life they must have either dialysis or a transplant
What stage will CKD patient start showing symptoms?
Until stage 4 or 5 patient may be asymptomatic
What is the syndrome of advanced CKD called?
Uraemia
What are uraemic symptoms?
Symptoms can involve almost any organ system
Earliest cardinal symptoms are malaise and fatigue
When is renal replacement therapy indicated?
When eGFR reaches <10 ml/min
What is eGFR?
Estimated GFR based on serum creatinine, age, sex and race.
Types of renal replacement therapy?
Transplants
Haemodialysis
Peritoneal dialysis
Conservative kidney management
What is dialysis?
a process where the solute composition of a solution, A, is altered by exposing solution A to a second solution, B, through a semipermeable membrane
Pre-requisites for dialysis?
A semi-permeable membrane
Adequate blood exposure to the membrane
Dialysis access
Anticoaglation
What is the semi-permeable membrane used in dialysis?
Artificial kidney in haemo
Peritoneal membrane in PD
Where is the blood needed for adequate blood exposure to the membrane taken from?
Haemo - extra-corporeal blood
PD - Mesenteric circulation
Where is dialysis access taken from?
Haemo - vascular
PD - peritoneum
When is anti-coagulation used?
haemodialysis only
Describe the types of vascular access taken in haemodialysis.
Permanent - Arteriovenous fistula or a AV prosthetic graft
Temporary - Tunnel venous catheter or a temporary venous catheter
What 2 things should you restrict from dialysis patients?
Fluids and diet
How is fluid restriction dictated?
By residual urine output and interdialytic weight gain
what is restricted in the diet of a dialysis patient?
Potassium
Sodium
Phosphate
Why is a patient on haemodialysis given heparin?
To prevent coagulation
Give a brief explanation of how PD works?
Dialysis solution is inserted into peritoneal cavity and uses the peritoneal mesothelium as a dialysis membrane
Types of PD?
CAPD - continuous ambulatory peritoneal dialysis
APD - Automated PD
Hybrid of both
When is a CAPD or APD done usually?
CAPD - day
APD - night
PD complications?
Exit site infection
PD peritonitis
Ultra-filtration failure
Encapsulating peritoneal sclerosis
If PD peritonitis is caused by a skin containment then what type of bacteria causes it?
Gram pos
If PD peritonitis is caused by bacteria of bowel origin then what type of bacteria causes it?
Gram neg
If there is a mix of gram pos and neg then what would be the cause of PD peritonitis?
A suspected complicated peritonitis - example perforation
What are the indications for dialysis in ESRD?
Advanced uraemia - GFR 5-10 ml/min
Severe acidosis - bicarb at <10 mmol/l
Treatment resistant hyperkalaemia - >6.5 mmol/l
Treatment resistant fluid overload
REVISION - what is the mnemonic used for remembering indications for dialysis in AKI?
AEIOU
A - acidosis E - electrolyte balance (K) I - intoxication O - overload U - uraemia
What is fluid overload? How is it treated?
Hypervolemia - treated via diuretics
Explain fluid balance in a haemodialysis patient.
restricted to 500-800 ml/ day
The intake allowed is calculated by - urine output+ insensible loss
What is fluid balance like in a PD patient?
Usually more liberal as continuous ultra-filtration is often achieved using this method
What is used to treat dialysis related anaemia?
Erythropoitein injections
IV iron supplements
What is used to treat dialysis related/renal bone disease?
Activated vitamin D - Calcitriol
Phosphate binders with meals
Complications of haemoD?
CV issues - intra-dialytic hypotension. cramps, arrythmia’s
Coagulation - clotting of vascular access, heparin issues
Allergic reactions to fialysis
Dialysis accidents = death (rare)
How is a dialysis modality chosen?
Patient choice via education and shared decision making
Perceptions of effectiveness
Cost
Limitations of dialysis?
Not the best substitute for a kidney
BUT
Only one available to keep ESRD patients alive
What is conservative kidney management?
Supportive care focusing on symptomatic management and anticipatory care planning
Involves a multi-professional approach
