Urgent RRT are initiated in certain critically ill patients with AKI and has been shown to reduce mortality rate. It is usually started in patients with severe metabolic acidosis, severe hyperkalemia, symptomatic uremia, refractory volume overload, elevated creatinine, oliguria or anuria, intractable pulmonary oedema, certain alcohol and drug intoxications.
There are multiple RRT options that are available in intensive care units. In general, continuous RRT (CRRT) are better tolerated and preferred in patients with hemodynamic instability due to slower rate of solute and fluid removal as compared to intermittent haemodialysis (IHD) where a higher risk of systemic hypotension is
present.
CRRT is also preferred for patients at risk of increased intracranial pressure and cerebral oedema.
IHD is used when patient is hemodynamically stable and require rapid removal of solute and volume. Even so, current studies are unable to support the superiority of either CRRT or IHD. The less commonly used sustained low efficiency dialysis (SLED) combines the modality of both IHD and CRRT but there is limited data on its drug dialysis clearance.