Indications for dialysis:
The threshold for dialysis in a critically ill patient is different from that of an ambulatory ward patient. Mortality in critically ill patients is related to time averaged urea during their stay, so that dialysis should be started earlier with the aim of maintaining a optimal state, rather than cyclical clearance of urea and metabolites.
The presence of two of the following would suggest dialysis should be considered:
Oliguria < 200 ml / 24 hrs
Oliguria < 50 ml / 12 hrs
Sever acidaemia
Hyperkalaemia
Plasma Urea > 30 mmol/L or uraemic syndrome (pericarditis, pnuemonitis, bone marrow suppression)
Plasma creatinine 0.3 mmol/L
Pulmonary oedema
Diuretic resistant cardiac failure
Anasarca (generalised oedema)
Selected overdose (salicylates, methanol, theophylline)
Imminent or ongoing massive blood product administration
The attempted removal of cytokines and inflammatory mediators is not yet proven to reduce mortality in humans.
Modes of Dialytic Therapy in the ICU
Standard intermittent Dialytic therapy: although still used, it is limited by resource availability and is probably not suitable for use in unstable patients.
Continuous veno-venous renal replacement therapy: A growing field of therapy in intensive care, this modality has become the mainstay of renal replacement in Christchurch Intensive Care.