Aortic Peak Flow Velocity As a Predictor of Fluid Responsiveness in Mechanically Ventilated Children: A Systematic Review and Meta-Analysis

Abstract

Objectives: This meta-analysis aimed to determine the accuracy of the respiratory variations in aortic peak flow velocity (delta Vpeak) in predicting fluid responsiveness and the moderators of that accuracy. Data Sources: We performed searches for studies that used delta Vpeak as a predictor of fluid responsiveness in mechanically ventilated children in PubMed, Embase, Scopus, and CINAHL from inception to June 20, 2022. Study Selection and Data Extraction: Fifteen studies (n = 452) were included in this meta-analysis. The diagnostic test data of the included studies were synthesized as pooled sensitivity, specificity, and diagnostic odds ratio (DOR) and the area under the curve (AUC) of the summary receiver operating characteristic of delta Vpeak. Data Synthesis: The delta Vpeak cutoff values applied in these studies had a median of 12.3% (interquartile range, 11.50–13.25%). The pooled sensitivity and specificity of delta Vpeak were 0.80 (95% CI, 0.71–0.87) and 0.82 (95% CI, 0.75–0.87), respectively. The DOR of delta Vpeak was 23.41 (95% CI, 11.61–47.20). The AUC of delta Vpeak was 0.87. Subgroup analyses revealed that the accuracy of delta Vpeak was not moderated by ventilator settings, measures of delta Vpeak, gold standard index, the cutoff gold standard value of responders, type and volume of fluid, duration of fluid challenge, use of vasoactive drugs, general anesthesia, and cardiopulmonary bypass. Conclusions: By using the cutoff of approximately 12.3%, the delta Vpeak appears to have good accuracy in predicting fluid responsiveness in mechanically ventilated children. The moderators of delta Vpeak predictability are not found.

Aortic peak flow variation as a predictor of fluid responsiveness in pediatric septic shock patients under mechanical ventilation

“…Another Meta-analysis from Sethasathien et al (7) incorporated a broader dataset of 452 cases across 15 studies, found a median delta Vpeak cutoff of 12,3 % with a pooled sensitivity of 80 % and specificity of 82 %, closely paralleling our study's findings.…”

“…Aortic Peak Flow Variation (APFV) derived from echocardiography has emerged as a potential predictor of fluid responsiveness in mechanically ventilated patients with septic shock. (7,8) Children present a distinct physiological and hemodynamic profile compared to adults, (9) which necessitates a thorough investigation of the applicability and accuracy of APFV as a predictor of fluid responsiveness in this demographic.…”

Passive Leg Raising–induced Changes in Peak Velocity Variation of Left Ventricular Outflow Tract to Predict Fluid Responsiveness in Postoperative Critically Ill Elderly Patients

“…In critically ill patients, bedside TTE played an important role in predicting fluid responsiveness and assessing hemodynamic conditions according to the increasing application of color Doppler ultrasonography (21). A recent systematic review and meta-analysis (22) reported that the respiratory variations in aortic peak flow velocity had good accuracy (an AUC of 0.87) in predicting fluid responsiveness in mechanically ventilated children with a cutoff of 12.3%. Pace et al (23) reported that respiratory cycle variations in aortic Vpeak provided a good predictor of fluid responsiveness in critically ill patients under mechanical ventilation with an AUC of 0.887.…”

Evaluating fluid overload in critically ill children

“…In daily clinical practice, a lower blood pressure is often interpreted as a state of hypovolemia instead of a low systemic vascular resistance, because cardiac output is not measured and clinical estimation of cardiac output is known to be very unreliable [23]. The beneficial effects of bolus fluid therapy may only be present in case of cardiac preload dependency, and from multiple studies we know that fluid bolus therapy leads to an increase in cardiac output in only 50% of critically ill children [24 ▪ ]. Indeed, a regime guiding fluid therapy based on vigorously implemented fluid responsiveness testing, showed a decline in infused fluids resulting in a lower cumulative fluid balance in adults [25].…”

“…Indeed, a regime guiding fluid therapy based on vigorously implemented fluid responsiveness testing, showed a decline in infused fluids resulting in a lower cumulative fluid balance in adults [25]. Methods to predict fluid responsiveness in children, like peak flow variations in the aorta measured using cardiac ultrasound, are often complex and seldomly implemented in daily care [24 ▪ ]. Furthermore, it is often believed that a reduced urine production in itself equals hypovolemia and this may also lead to excess fluid prescription.…”