Effects of Fluid Balance Control in Critically Ill Patients
Status:
Completed
Trial end date:
2020-05-25
Target enrollment:
Participant gender:
Summary
Most ICU patients develop a positive fluid balance, mainly during the two first weeks of
their stay. The causes are multifactorial: a reduced urine output subsequent to shock state,
positive pressure mechanical ventilation, acute renal failure, post-operative period of major
surgical procedures, and simultaneous fluid loading to maintain volemia and acceptable
arterial pressure. Additionally, the efficacy of fluid loading is frequently suboptimal, in
relation to severe hypoalbuminemia and inflammatory capillary leakage. This results usually
in a cumulated positive fluid balance of more than 10 litres at the end of the first week of
stay. A high number of studies have showed that such a positive fluid balance was an
independent factor of worse prognosis in selected populations of ICU patients: acute renal
failure, acute respiratory distress syndrome (ARDS), sepsis, post-operative of high risk
surgery. However, little is known about the putative causal role of positive fluid balance by
itself on outcome. However, in two randomized controlled studies in patients with ARDS, a
strategy of fluid balance control has been demonstrated to reduce time under mechanical
ventilation and ICU length of stay with no noticeable adverse effects. Although avoiding
fluid overload is now recommended in ARDS management, there is no evidence that this approach
would be beneficial in a more general population of ICU patients (i.e. with sepsis, acute
renal failure, mechanical ventilation). In addition, fluid restriction -mainly if applied
early could be deleterious in reducing both tissue oxygen delivery and perfusion pressure.
There is a place for a prospective study comparing a "conventional" attitude based on liberal
fluid management throughout the ICU stay with a restrictive approach aiming at controlling
fluid balance, at least as soon as the patient circulatory status is stabilized. The latter
approach would use a simple algorithm using fluid restriction and diuretics based on daily
weighing, a common procedure in the ICU, probably more reliable than cumulative measurement
of fluid movements in patients whose limits have been underlined.