Respiratory variation in aortic blood flow peak velocity to predict fluid responsiveness in mechanically ventilated children: a systematic review and meta-analysis

BackgroundDynamic indices of preload have been shown to better predict fluid responsiveness than static variables in mechanically ventilated adults. In children, dynamic predictors of fluid responsiveness have not yet been extensively studied. AimTo evaluate the diagnostic accuracy of respiratory variation in aortic blood flow peak velocity (VPeak) for the prediction of fluid responsiveness in mechanically ventilated children. MethodPubMed, Embase, and the Cochrane Database of Systematic Reviews were screened for studies relevant to the use of VPeak to predict fluid responsiveness in children receiving mechanical ventilation. Clinical trials published as full-text articles in indexed journals without language restriction were included. We calculated the pooled values of sensitivity, specificity, diagnostic odds ratio (DOR), and positive and negative likelihood ratio using a random-effects model. ResultsIn total, six studies (163 participants) met the inclusion criteria. Data are reported as point estimate with 95% confidence interval. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and DOR of VPeak to predict fluid responsiveness for the overall population were 92.0% (84.1-96.7), 85.5% (75.6-92.5), 4.89 (2.92-8.18), 0.13 (0.07-0.25), and 50.44 (17.70-143.74), respectively. The area under the summary receiver operating characteristic curve was 0.94. Cutoff values for VPeak to predict fluid responsiveness varied across studies, ranging from 7% to 20%. ConclusionOur results confirm that the VPeak is an accurate predictor of fluid responsiveness in children under mechanical ventilation. However, the question of the optimal cutoff value of VPeak to predict fluid responsiveness remains uncertain, as there are important variations between original publications, and needs to be resolved in further studies. The potential impact of intraoperative cardiac output optimization using goal-directed fluid therapy based on VPeak on the perioperative outcome in the pediatric population should be subsequently evaluated.