Predicting Fluid Responsiveness in Mechanically Ventilated Critically Ill Children Using Transthoracic Echocardiography (PREDIPEN)

Predicting Fluid Responsiveness in Mechanically Ventilated Critically Ill Children Using Transthoracic Echocardiography

Predicting Fluid Responsiveness in Mechanically Ventilated Critically Ill Children and Neonates Using Transthoracic Echocardiography

Initial fluid resuscitation remains the first treatment step for most children experiencing circulatory failure and/or systemic hypotension. Only one-half of these patients respond to fluid administration by a significant increase in cardiac output. A positive fluid balance is a poor prognostic factor that increases mortality. There are few markers validated in children to assess volume reactivity by dynamic ultrasound parameters mainly based on heart-lung interaction. In this work, the investigators propose to investigate whether dynamic parameters validated in adults, such as the superior vena caval collapsibility and the variability of cardiac output during an end-expiratory and end-inspiratory occlusion, are also reliable indicators of volume responsiveness in sedated children under controlled-mode ventilation.

After standardized volume expansion, patients who present an increase of cardiac index measured by transthoracic echocardiography greater than or equal to 15% of baseline measurement will be considered responders . A previous similar study using respiratory variations in aortic blood flow to predict fluid responsiveness in ventilated children reported a ROC curve area 0.85, while the prevalence rate of circulatory failure was 50%. Given these assumptions, a sample size of 38 subjects per group (Responders / No responders) was estimated to provide a AUC equivalent. A total of 76 subjects should be included.

children, critically ill, fluid therapy, fluid responsiveness, hemodynamics, hypovolemia, shock, echocardiography

At baseline before standardized volume expansion, a first set of echocardiographic measurements will be performed. Then, we will perform 15-second end-expiratory and end-inspiratory occlusions. Occlusions will be separated by 1 minute to allow the cardiac index to return to its baseline value. A last set of measurements will be performed after fluid administration. Ventilatory settings and other treatments will remain unchanged during the study period.

At baseline before standardized volume expansion, a first set of echocardiographic measurements will be performed. Then, we will perform 15-second end-expiratory and end-inspiratory occlusions. Occlusions will be separated by 1 minute to allow the cardiac index to return to its baseline value. A last set of measurements will be performed after fluid administration. Ventilatory settings and other treatments will remain unchanged during the study period.

After fluid administration, patients who present an increase of cardiac index measured by transthoracic echocardiography greater than or equal to 15% of baseline measurement will be considered responders .

ETCO2 measurements using sidestream microstream technology before and after fluid administration will be compared to cardiac index measured by transthoracic echocardiography, ETCO2 increment of 5% is expected in responders patients.

Inclusion Criteria : Patient < 18 years (child and neonate) Sedated and mechanically ventilated under controlled-mode ventilation In whom fluid administration was planned by the attending physicians Exclusion Criteria : High-frequency oscillatory ventilation Cardiac arrhythmia Congenital heart defect

Durand P, Chevret L, Essouri S, Haas V, Devictor D. Respiratory variations in aortic blood flow predict fluid responsiveness in ventilated children. Intensive Care Med. 2008 May;34(5):888-94. doi: 10.1007/s00134-008-1021-z. Epub 2008 Feb 8.