Objective: To assess the reliability of the variability of the inferior vena cava diameter as an indicator of fluid responsiveness in critically ill patients with atrial fibrillation.
Methods: Adult critically ill patients with atrial fibrillation requiring mechanical ventilation were enrolled. The variability of the inferior vena cava diameter (V(IVC)) was measured during a breath and then calculated as the maximum diameter (Dmax) minus minimum diameter (Dmin) divided by Dmin. All the hemodynamic parameters were collected at baseline and after a manoeuvre of passive leg raising (PLR). A 15% of VTI increase after the PLR was the criterion to identify the patients with or without fluid responsiveness. ROC curve was used to assess the sensitivity and specificity of V(IVC) as an indicator of fluid responsiveness for critically ill patients with atrial fibrillation.
Results: There were 34 patients enrolled in our study, with 14 of them responsed to PLR and the rest 20 did not. For patients with fluid responsiveness V(IVC) was significantly higher than patients without fluid responsiveness. The sensitivity and specificity of V(IVC) ≥ 16% to predict fluid responsiveness in patients with atrial fibrillation were 57.1% and 89.9% respectively.
Conclusion: V(IVC) proved to be a reliable predictor of fluid responsiveness in critical ill patients with atrial fibrillation.