Dynamic variables predict fluid responsiveness in pre-school and school children undergoing neurosurgery: a prospective observational study

Abstract

Background: The evidence that plethysmographic variability index (PVI), pulse pressure variation (PPV), FloTrac/Vigileo-derived stroke volume variation (SVV), and Ea dyn (dynamic arterial elastance) predict fluid responsiveness in children is limited by conflicting results. We aim to evaluate their accuracy and reliability to predict fluid responsiveness after induction in children aged 4-9 years undergoing major neurosurgery.Methods: Children aged 4-9 years undergoing intracranial epileptic foci excision were enrolled. After the induction of anesthesia, fluid loading with 10 mL/kg of Ringer's solution over 10 min was administered before surgical incision. PVI, PPV, SVV, and Ea dyn were measured before and within 5 min after fluid loading. Respiratory variation in aortic blood flow peak velocity (∆Vpeak) >15% at baseline, measured using transthoracic echocardiography, identified fluid "responders". The abilities of dynamic variables to predict an increase in mean arterial pressure (MAP) of >10% following fluid loading were also assessed.Results: Fourteen (31.8%) of forty-four patients were responders defined by a baseline ∆Vpeak >15%.Before fluid loading, only the PVI value was significantly different between R and NR (P=0.017). Baseline PVI showed fair diagnostic accuracy for fluid responsiveness, with an area under the curve (AUROC) of 0.735 and the cutoff value of 13%. The R group showed a significantly greater absolute change in PPV and SVV after fluid loading from baseline compared with the NR group (P=0.021and 0.040, respectively). The absolute change in the PPV and SVV values from baseline was greater in R than those in NR (P=0.021 and 0.040, respectively). Twenty (45.5%) showed a MAP increase of >10% following fluid loading and were defined as responders. Baseline ∆Vpeak and SVV showed fair predictive values for a MAP increase of >10% (AUROC =0.758 and 0.715, respectively).Conclusions: PVI at baseline showed fair reliability to predict fluid responsiveness after anesthesia induction in mechanically ventilated children aged 4-9 years undergoing neurosurgery. Baseline ∆Vpeak and SVV were fairly predictive for an increase in MAP following fluid loading.

Dynamic variables to predict fluid responsiveness in young children

“…Our group recently reported the results in children aged more than 3 years old with regard to the reliabilities of dynamic variables for predicting fluid responsiveness in the same clinical setting. 20 Despite the different definition of fluid responsiveness after induction in these two studies, PVI was consistently proved to be an acceptable indicator for a CI increase following fluid loading, which appeared to be more accurate for young children than for older ones. Different from pressure-based PPV and SVV, PVI serves as a volume-dependent variable.…”

“…Pressured‐based FloTrac/Vigileo‐SVV, Ea dyn , PPV, and SVI c were poor indicators or not useful for fluid response prediction in this clinical setting. Our group recently reported the results in children aged more than 3 years old with regard to the reliabilities of dynamic variables for predicting fluid responsiveness in the same clinical setting 20 . Despite the different definition of fluid responsiveness after induction in these two studies, PVI was consistently proved to be an acceptable indicator for a CI increase following fluid loading, which appeared to be more accurate for young children than for older ones.…”

“…We followed the Standards for Reporting of Diagnostic Accuracy (STARD) statement to report our study. The method was also described in Song's study 20 …”

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

“…Figure 2 illustrates the risk of bias and the applicability concerns of the included studies based on the QUADAS-2 tool. There were two studies which had high risk of bias on the index test and one on the reference standard (18, 26, 32). No studies had high risk of bias on patient selection and flow/timing or applicability concerns.…”

“…The range of these cutoff values could potentially be influenced by the differences in cutoff values of the gold standard index, the use of medications such as vasopressors or anesthesia and the clinical settings of fluid resuscitation. Whereas most studies classified fluid responders as having an increase of 15% or more of the gold standard index (18–21, 23–25, 27–30, 34), some studies categorized fluid responders using only a 10% increase (22, 26, 32). This, in turn, resulted in the observed fluctuations of the delta Vpeak values.…”