Volume management in haemodialysis patients.

Abstract

Accumulating evidence supports the important contribution of volume-related metrics to morbidity and mortality in patients receiving chronic haemodialysis. The purpose of this review is to summarize recent advances in the understanding and management of volume status in this high-risk group. Delivery of optimal volume management involves three key components: accurate estimation of volume status, correction of extracellular fluid overload and prevention of intradialytic instability. The lack of a gold standard for assessing volume status makes accurate estimation difficult to achieve; clinical examination has insufficient sensitivity and specificity, while tools to assist in the objective measurement of extracellular fluid volume require further validation. Hypervolemia is common in patients on chronic haemodialysis and substantially increases the risk of morbidity and mortality. Rapid correction of hypervolemia should be avoided due to the risk of precipitating intradialytic hypotension and hypoperfusion of vital end-organs, including the heart, brain, liver, gut and kidneys. Evidence-based interventions to aid in normalizing extracellular fluid volume are urgently needed; several targeted strategies are currently being evaluated. Many centres have successfully implemented local protocols and programmes to enhance volume management. Achieving normal volume status is a fundamental goal of haemodialysis. Novel methods of assessing and restoring extracellular fluid volume while maintaining intradialytic stability are currently undergoing evaluation. Implementation of volume-related strategies into clinical practice is feasible and may improve patient outcome.