Indicateurs cliniques du remplissage vasculaire au cours de l'insuffisance circulatoire aiguë

In spite of an improvement of hemodynamic monitoring, the clinical signs remain the usual criteria in the decision for fluid challenge during acute circulatory failure, as well as in the evaluation of the therapeutic efficiency. They have the advantage to be immediately and easily accessible. The decrease of blood flow causes an immediate sympatomimetic stimulation and complex, heterogeneous modifications of blood flow to different organs. The sedation strongly decreases sympatomimetic stimulation and modifies the adaptation of the blood flow decrease. If they are taken separately, clinical signs have a low sensibility and specificity because of multifactorial influences independent of the blood volume. Clinical context and anamnesis are thus, fundamental factors to decide fluid loading. Postural maneuvers, especially passive leg raising, improve the accuracy of static clinical signs. For ventilated patients, when using an usual monitor, noninvasive functional hemodynamic monitoring of fluid, responsiveness is possible with the use of pulse oxymeter plethysmographic wave analysis and the use of end-tidal CO2 monitoring. When replacing clinical signs in their context and associating them, one can have a body of argument allowing to establish an early indication for fluid challenge, before a more sophisticated monitoring can be used to refine therapeutics in second time.