Mean systemic filling pressure to predict the response to forced fluid removal by continuous renal replacement therapy

A positive fluid balance is associated with a significant negative influence on
survival. Continuous renal replacement therapy (CRRT) can, in addition to
removing solutes, also be used to remove large amounts of fluids from the body,
especially in patients with a positive fluid balance. However, some patients do
not tolerate the removal of fluid: they are not able to shift fluid volume from
the interstitial to the intravascular space, leading to a severe decrease in
arterial blood pressure. Other patients are perfectly able to shift extra- to
intravascular volume and they will remain hemodynamically stable. In this study
we want to distinguish these two patient groups by calculating the mean
systemic filling pressure before the start of fluid withdrawal.

To distinguish patients who tolerate fluid removal by CRRT from those who
become hemodynamically instable (hypotensive) during this procedure.

Prospective observational, diagnostic study.

Patients will be subjected to forced fluid removal during continuous renal
replacement therapy.

There is no additional risk for the patients concerning the extra measurements
(non-invasive peripheral perfusion measurements) and data recording. However
there is a possible risk that patients become hypotensive. For this reason we
defined a MAP lower threshold of 60 mmHg. In the situation where MAP decreases
under the lower threshold value, Norepinephrine will be increased to maintain
MAP * 60 mmHg.