Does the Response to a Mini-fluid Challenge of 3ml/kg in 2 Minutes Predict Fluid Responsiveness for Pediatric Patient? (PEDIFLUID)

The main objective is to determine whether the new test "the stroke volume variation after fluid challenge of 3ml/Kg" provides information about fluid responsiveness namely increased cardiac output. This new test will be compared to "gold standard" that is, "the stroke volume variation after standard fluid challenge of 15ml/Kg". It is the evaluation of the diagnostic accuracy of a diagnostic test based on an index obtained by transthoracic cardiac echocardiography for diagnosing fluid responsiveness. This index is the stroke volume variation measured by transthoracic cardiac echography.

The study will include anesthetized patients undergoing scheduled surgery. For hemodynamic optimization, these patients will benefit, early after anaesthetic induction, before the surgical procedure has started, from a fluid challenge of 15ml/kg achieved in two stages (3 ml/Kg then 12 ml/kg) separated by an interval of one minute. Three-time hemodynamic will be analyzed.

• T0: basal
• T1: one minute after first vascular filling with 3ml/Kg in 2 minutes
• T2: one minute after second vascular filling with 12 ml/Kg in 8 minutes which is performed one minute after the end of the first filling (a total of 15 ml/kg)

At each time, we will retrieve a collection of hemodynamic data (stroke volume, cardiac output) obtained by transthoracic echocardiography, standard method to assess fluid responsiveness. And at the same times, the PVI and hemodynamic parameters obtained by esophageal Doppler will be noted.