Intradialytic hypertension: it is time to act.

Intradialytic hypertension (IDH) is defined by blood pressure (BP) values during and at the end of the dialysis session exceeding BP values at dialysis onset. It occurs in around 10% of hemodialysis (HD) patients. It is associated with HD patients' hospitalization and increased risk of death. Many hypotheses have been proposed to explain this phenomenon. Recent studies and reports highlight the important role of fluid overload, hemodynamic changes, and increased endothelin level. The importance of other hypotheses such as the renin-angiotensin system activation, sympathetic overactivity and ionic variations seems secondary but it deserves to be confirmed. Fluid removal remains the key point for treating IDH. Several important unanswered questions remain and the need for further research is highlighted. Copyright 2010 S. Karger AG, Basel.