Continuous Renal Replacement in the Critically Ill

Key Words: KIDNEY: acute renal failure, continuous renal replacement, critical care Acute renal failure (ARF) occurring in critically ill patients in the intensive care unit (ICU) is a common problem.It is associated with a high mortality, particularly when it forms part of a syndrome of multi-organ failure.l • 5 Acute renal failure complicates the management of such patients because the resultant inability to remove toxic metabolites and to correct acid-base and electrolyte abnormalities is frequently associated with fluid overload.This may lead to pulmonary oedema and hypoxia and also to an increase in peripheral interstitial water with consequent decreased tissue perfusion.6 Adequate enteral or parenteral nutritional support then becomes difficult because of the risk of further exacerbating fluid overload.In the past, the standard methods of renal replacement therapy in such patients have been either intermittent machine-driven haemodialysis (HD) or peritoneal dialysis (PD), both of which have significant disadvantages in this group of patients.More recently, a wide variety of continuous renal replacement therapies (CRRT) have been introduced, which involve an extra-corporeal blood circuit and some kind of haemofilter.•StafT Specialist.tDirector of Anaesthetics, Intensive Care and Coronary Care.