(uro-renal) dialysis & kidney transplant Flashcards
what are the two types of dialysis?
haemodialysis
peritoneal dialysis
explain how haemodialysis occurs
two compartments: one for patient’s blood and the other for the dialysate (separated by a semi-permeable membrane)
1) extracorporeal removal of waste products – urea and freely filtered creatinine from the blood (small enough to pass the semi-permeable membrane barrier)
2) filtration occurs between the semi-permeable membrane to regulate levels in the plasma again
3) concentration gradients maintained due to removal of used dialysate and replenishing of fresh dialysate
- counter-current motion between the blood and dialysate
- specific components of diastyle are determined by the nephrologist, dependent on the individual & monitored
explain how peritoneal dialysis occurs
the peritoneum acts as the semi-permeable membrane with the dialysate being pumped into the peritoneal cavity (bw visceral and parietal peritoneum)
here, the exchange of waste substances and dissolved substances w the blood occurs and circulation ensures a concentration gradient is maintained and once dialysis is complete, the used dialysate is pumped out
(removes excess fluid – correct electrolyte problems and removes toxins in individuals with renal failure)
where is haemodialysis carried out?
generally, requires dialysis centre visits (BUT can also be performed at home)
where is peritoneal dialysis carried out?
performed at home, generally overnight
= saves journey time and travel requirement
how often does haemodialysis need to be carried out?
approx 3-4.5 hours of treatment 3 times per week
= allows for 4 treatment-free days per week
how often does peritoneal dialysis need to be carried out?
normally 7 days a week but can often have a weekend off if needed
to what extent is the diet constricted with haemodialysis?
strict dietary constraints and salt/water intake restrictions
(stricter than peritoneal dialysis)
to what extent is the diet constricted with peritoneal dialysis?
comparatively fewer constraints for food and water intake (less compared to haemodialysis, but still present)
what are the access needs for haemodialysis?
ideally an arteriovenous fistula (needs an operation under local anaesthetic) OR a central venous line (risk of bacterial infection)
why is peritoneal dialysis usually preferred by people with busy schedules?
can travel easily – machine packs into a wheelie suitcase and fluids delivered by the companies internationally
day time exchanges of fluid can be done anywhere as long as you can wash hands (reduced infection risk!)
what are the possible chances of infection with peritoneal dialysis?
due to catheter or such as peritonitis
what factors must be considered when selecting a live kidney donor?
- age
- family history of kidney disease
- comorbidities
- two healthy kidneys (USS for size, GFR for function, assess haematuria and proteinuria)
- financial stability
- mental health history
- future pregnancy
- kidney match (HLA typing, blood typing, serum crossmatch)
what is HLA typing?
HLA (proteins/antigens found on cell surfaces) typing
= procedure in which the tissues of a prospective donor and recipient are tested for compatibility prior to transplantation
where is the donor kidney transplanted to?
different anatomical location to native kidneys
