Use of Pulse Pressure Variation as Predictor of Fluid Responsiveness in Patients Ventilated With Low Tidal Volume: A Systematic Review and Meta-Analysis

Abstract

Introduction: Pulse pressure variation (PPV) has been shown to be useful to predict fluid responsiveness in patients ventilated at tidal volume (Vt) >8 mL kg−1. Nevertheless, most conditions in critical care force to use lower Vt. Thus, we sought to evaluate the operative performance of PPV when a Vt ⩽8 mL kg−1 is used during mechanical ventilation support. Methods: We searched PubMed and Embase databases for articles evaluating the operative performance of PPV as a predictor of fluid responsiveness in critical care and perioperative adult patients ventilated with tidal volume ⩽8 mL kg−1 without respiratory effort and arrhythmias, between January 1990 and January 2019. We included cohort and cross-sectional studies. Two authors performed an Independently selection using predefined terms of search. The fitted data of sensitivity, specificity, and area under the curve (AUC) were assessed by bivariate and hierarchical analyses. Results: We retrieved 19 trials with a total of 777 patients and a total of 935 fluid challenges. The fitted sensitivity of PPV to predict fluid responsiveness during mechanical ventilation at Vt ⩽8 mL kg−1 was 0.65 (95% confidence interval [CI]: 0.57-0.73), the specificity was 0.79 (95% CI: 0.73-0.84), and the AUC was 0.75. The diagnostic odds ratio was 5.5 (95% CI: 3.08-10.01, P < .001) by the random-effects model. Conclusions: Pulse pressure variation shows a fair operative performance as a predictor of fluid responsiveness in critical care and perioperative patients ventilated with a tidal volume ⩽8 mL kg−1 without respiratory effort and arrhythmias.

Correlation between Carotid and Brachial Artery Velocity Time Integral and Their Comparison to Pulse Pressure Variation and Stroke Volume Variation for Assessing Fluid Responsiveness

“… 6 The performance of PPV was evaluated in a systematic review and meta-analysis of 19 studies (777 patients) ventilated with tidal volumes <8 mL/kg. 16 In 935 fluid challenges, 51.1% patients were found to be fluid responsive. PPV of 10% had the fitted sensitivity of 0.65 (95% CI: 0.57–0.73) to predict FR, and the specificity was 0.79 (95% CI: 0.73–0.84).…”

“…This is similar to our findings for PPV, with sensitivity of 77% and a specificity of 72% but with lower AUROC. 16 The dynamic indices rely on change in intrathoracic pressure. In patients with low lung compliance due to ARDS, the changes in intrathoracic pressure induced by low TV are too small to affect the stroke volume, leading to inability of PPV or SVV to predict fluid responsiveness.…”

The effect of vasoconstriction on intestinal perfusion is determined by preload dependency: A prospective observational study

“…Preload dependency was assessed by SVV and patients were ventilated with a tidal volume (TV) of 7 ml kg −1 ideal body weight, which is associated with lower levels of postoperative complications 29 . Low levels of TV have previously demonstrated to be feasible when using SVV for assessment of preload dependency 30,31 …”

Clinical Application of the Fluid Challenge Approach in Goal-Directed Fluid Therapy: What Can We Learn From Human Studies?

“…According to a meta-analysis, PPV was superior to predict responsiveness than other dynamic preload indexes in human patients under mechanical ventilation with tidal volumes ranging from 8 to 12 ml/kg ( 31 ). Although, PPV values >12.5% accurately discriminate responders from non-responders to a fluid challenge ( 31 ), this index has limited clinical application in the ICU setting because of inaccurate prediction of responsiveness in patients ventilated with low tidal volumes (<8 ml/kg) ( 34 , 35 ). The ability of ΔV peak , PPV, SPV, PVI, and SVV PCA to predict the response to a fluid challenge has been assessed in anesthetized mechanically ventilated dogs ( 12 – 16 , 18 , 21 , 22 ).…”