title: Renal replacement therapy in the intensive care unit.
abstract: OBJECTIVE
  To present an overview of the principles of renal replacement therapy, its application in the critically ill patient, and an update of recent research in this area.
  
  
  METHODS
  Articles and published peer-review abstracts on the beneficial effects of continuous renal replacement therapy (CCRT) in the critically ill patient.
  
  
  RESULTS
  Renal replacement therapy utilizes dialysers that enable solute and solvent to move across semipermeable membranes in either a convective or diffusive fashion. In the critically ill patient, percutaneous vascular access and improvement in dialysis machines, have facilitated the intensive care unit management of acute renal failure in these patients. Currently, CCRT is most often used to manage the critically ill patient with acute renal failure, as it is less likely to produce hypotension when compared with intermittent haemodialysis. However, CCRT has been expanded to manage critically ill patients with multiple organ failure, with the demonstration that it is able to remove or adsorb putative mediators of organ dysfunction. While there are experimental and uncontrolled clinical data that have suggested that this form of therapy is beneficial, currently there are no prospective randomised, controlled trials that have confirmed this benefit when used in these patients.
  
  
  CONCLUSIONS
  Continuous renal replacement therapy has become commonplace in the management of critically ill patients with acute renal failure. It has the advantage of causing less hypotension and a more gradual return of the fluid and electrolyte status, when compared with intermittent haemodialysis. Recent evidence suggests that it may also be a useful immunomodulator and may be beneficial in the management of patients with multiple organ failure.
authors.affiliation: Intensive Care Unit, Austin & Repatriation Medical Centre, Melbourne, Victoria. rb@austin.unimelb.edu.au
authors.forename: R
authors.initials: R
authors.lastname: Bellomo
authors.forename: C
authors.initials: C
authors.lastname: Ronco