title: Respiratory variations in aortic blood flow predict fluid responsiveness in ventilated children.
abstract: OBJECTIVE
  To investigate whether respiratory variations in aortic blood flow velocity (DeltaVpeak ao), systolic arterial pressure (DeltaPS) and pulse pressure (DeltaPP) could accurately predict fluid responsiveness in ventilated children.
  
  
  METHODS
  Prospective study in a 18-bed pediatric intensive care unit.
  
  
  METHODS
  Twenty-six children [median age 28.5 (16-44) months] with preserved left ventricular (LV) function.
  
  
  METHODS
  Standardized volume expansion (VE).
  
  
  RESULTS
  Analysis of aortic blood flow by transthoracic pulsed-Doppler allowed LV stroke volume measurement and on-line DeltaVpeak ao calculation. The VE-induced increase in LV stroke volume was >15% in 18 patients (responders) and <15% in 8 (non-responders). Before VE, the DeltaVpeak ao in responders was higher than that in non-responders [19% (12.1-26.3) vs. 9% (7.3-11.8), p=0.001], whereas DeltaPP and DeltaPS did not significantly differ between groups. The prediction of fluid responsiveness was higher with DeltaVpeak ao [ROC curve area 0.85 (95% IC 0.99-1.8), p=0.001] than with DeltaPS (0.64) or DeltaPP (0.59). The best cut-off for DeltaVpeak ao was 12%, with sensitivity, specificity, and positive and negative predictive values of 81.2%, 85.7%, 93% and 66.6%, respectively. A positive linear correlation was found between baseline DeltaVpeak ao and VE-induced gain in stroke volume (rho=0.68, p=0.001).
  
  
  CONCLUSIONS
  While respiratory variations in aortic blood flow velocity measured by pulsed Doppler before VE accurately predict the effects of VE, DeltaPS and DeltaPP are of little value in ventilated children.
authors.affiliation: Pediatric Intensive Care Unit, Bicêtre Hospital, 78 rue du Gal Leclerc, 94275 Le Kremlin Bicêtre, France. philippe.durand@bct.ap-hop-paris.fr
authors.forename: Philippe
authors.initials: P
authors.lastname: Durand
authors.forename: Laurent
authors.initials: L
authors.lastname: Chevret
authors.forename: Sandrine
authors.initials: S
authors.lastname: Essouri
authors.forename: Vincent
authors.initials: V
authors.lastname: Haas
authors.forename: Denis
authors.initials: D
authors.lastname: Devictor
mesh_terms: D001011:Aorta / Q000000981:diagnostic imaging*; D001783:Blood Flow Velocity; D002675:Child, Preschool; D018619:Echocardiography, Doppler, Pulsed; D005440:Fluid Therapy; D006801:Humans; D020896:Hypovolemia / Q000517:prevention & control; D007223:Infant; D018579:Patient Selection; D019095:Point-of-Care Systems; D011446:Prospective Studies; D012372:ROC Curve; D012121:Respiration, Artificial; D012680:Sensitivity and Specificity; D012772:Shock, Septic / Q000628:therapy*; D013318:Stroke Volume