Understanding the continuous renal replacement therapy circuit for acute renal failure support: a quality issue in the intensive care unit.

Delivery of renal replacement therapy is now a core competency of intensive care nursing. The safe and effective delivery of this form of therapy is a quality issue for intensive care, requiring an understanding of the principles underlying therapy and the functioning of machines used. Continuous hemofiltration, first described in 1977, used a system where blood flowed from arterial to venous cannulas through a small-volume, low-resistance, and high-flux filter. Monitoring of these early systems was limited, and without a machine interface, less nursing expertise was required. Current continuous renal replacement therapy machines offer user-friendly interfaces, cassette-style circuits, and comprehensive circuit diagnostics and monitoring. Although these machines conceal complexity behind a user-friendly interface, it remains important that nurses have sufficient knowledge for their use and the ability to compare and contrast circuit setups and functions for optimal and efficient treatment.