Up to 70% of patients require renal replacement therapy or dialysis. Dialysis is renal therapy via diffusion of small solutes, whereas filtration is the convection of large solutes. Early treatment is better, obviously…
- intermittent hemodialysis: is easier to implement, more practical, better solute clearance and fewer bleeding complications
- continuous dialysis: better for hemodynamically unstable patients, if have renal and hepatic failure, or acute brain injury
- requires continuous anticoagulation with heparin or UFH
- citrate may cause electrolyte issues (chelates ionized Ca)
- CVVHDF=continuous venovenous hemodiafiltration=dialysis +filtration. The #1 modality in the ICU. Large volume, requires fluid replacement.
- CAVHD or AVHDF requires arterial cannulation, and is unreliable in pts with low BP, PVD. More risky.
- peritoneal dialysis
- SLEDD (hybrid of intermittent and continuous): more flexible than continuous, less need for anticoagulation, but has the same efficacy as continuous