Assessment of fluid responsiveness by inferior vena cava diameter variation in post-pneumonectomy patients

Diagnostic Accuracy of Ultrasonographic Respiratory Variation in the Inferior Vena Cava, Subclavian Vein, Internal Jugular Vein, and Femoral Vein Diameter to Predict Fluid Responsiveness: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate the ultrasonographic variation of the diameter of the inferior vena cava (IVC), internal jugular vein (IJV), subclavian vein (SCV), and femoral vein (FV) to predict fluid responsiveness in critically ill patients. Relevant articles were obtained by searching PubMed, EMBASE, and Cochrane databases (articles up to 21 October 2021). The number of true positives, false positives, false negatives, and true negatives for the index test to predict fluid responsiveness was collected. We used a hierarchical summary receiver operating characteristics model and bivariate model for meta-analysis. Finally, 30 studies comprising 1719 patients were included in this review. The ultrasonographic variation of the IVC showed a pooled sensitivity and specificity of 0.75 and 0.83, respectively. The area under the receiver operating characteristics curve was 0.86. In the subgroup analysis, there was no difference between patients on mechanical ventilation and those breathing spontaneously. In terms of the IJV, SCV, and FV, meta-analysis was not conducted due to the limited number of studies. The ultrasonographic measurement of the variation in diameter of the IVC has a favorable diagnostic accuracy for predicting fluid responsiveness in critically ill patients. However, there was insufficient evidence in terms of the IJV, SCV, and FV.

Ultrasound Assessment of the Inferior Vena Cava for Fluid Responsiveness: Making the Case for Skepticism

Determining whether a patient in shock is in a state of fluid responsiveness (FR) has long been the Holy Grail for clinicians who care for acutely ill patients. While various tools have been put forth as solutions to this important problem, ultrasound assessment of the inferior vena cava has received particular attention of late. Dozens of studies have examined its ability to determine whether a patient should receive volume expansion, and general enthusiasm has been strengthened by the fact that it is easy to perform and non-invasive, unlike many competing FR tests. A deeper examination of the technique, however, reveals important concerns regarding inaccuracies in measurement and a high prevalence of confounding factors. Furthermore, a detailed review of the evidence (small individual studies, multiple meta-analyses, and a single large trial) reveals that the tool performs poorly in general and is unlikely to be helpful at the bedside in circumstances where genuine clinical uncertainty exists.

Dynamic assessment of the central vein throughout the cardiac cycle in adults with no right heart disease by cardiac CT

PURPOSE

The aim of this study was to investigate the effect of the cardiac cycle on the vena cava and determine the phase of measuring maximum diameters.

METHODS

A total of 152 patients who underwent cardiac computed tomography (CT) were included. Patients' basic information was collected. The major axis, minor axis, and cross-sectional area (CSA) of the vena cava in 10 phases reconstructed at 10% step from 5% to 95% R-R interval were measured in four planes (SVC1 layer: the bifurcation of the pulmonary artery; SVC2 layer: the superior vena cava (SVC) into the right atrium; IVC1 layer: the intersection of the inferior vena cava (IVC) and the right atrium; IVC2 layer: the IVC into the anterior hepatic plane). The difference in vena cava diameters between cardiac cycles was determined using the linear mixed model.

RESULTS

The variations in diameter and CSA of the SVC in cardiac cycles were statistically significant (p < 0.05), while those of the suprahepatic IVC were not. In the SVC1 layer, the maximum value of the SVC major and minor axes was observed in 85% and 45% phases, respectively, while that in the SVC2 layer was observed in 45% phases. The maximum SVC diameters in the SVC1 and SVC2 layers were 19.48 ± 2.57 mm and 17.43 ± 3.09 mm, respectively. The SVC and IVC diameters and CSA were positively correlated with the body surface area in the linear mixed model.

CONCLUSION

The maximum SVC diameter and CSA were mostly observed in 45% phase, which provides a reference for selecting the best phase to measure the abnormality of vena cava diameter in the future.

Assessment of fluid responsiveness by inferior vena cava diameter variation in post-pneumonectomy patients

Aim

First, the inferior vena cava dilatation index (DIVC) was measured by ultrasound, and then the reliability of DIVC as an indicator to predict volume responsiveness in patients undergoing mechanical ventilation after pneumonectomy was evaluated.

Methods

Pulse indicator continuous cardiac output (Picco) as gold standard was performed to sedated mechanically ventilated post‐pneumonectomy patients in intensive care unit of Nanjing Thoracic Hospital from August 2014 to December 2016. Meanwhile, ultrasound measurement to inferior vena cava (IVC) diameter at the end inspiration (D_max) and the end of expiration (D_min) was performed. DIVC = (D_max − D_min)/D_min. Above values were recorded at baseline and then after fluid resuscitation challenge (7 mL/kg hydroxyethyl starch). An increase in cardiac index of more than 15% was used as the standard for fluid responsiveness. Patients were divided into responsive group and non‐responsive group. A receiver operating characteristic (ROC) curve was then used to determine the sensitivity and specificity of DIVC in predicting fluid responsiveness after pneumonectomy.

Results

Eighteen patients were enrolled. 10 patients were divided into responsive group and eight in non‐responsive group. DIVC in responsive group was significantly higher than in non‐responsive group (P < 0.01). By setting DIVC ≥ 15% as a measure of fluid responsiveness, sensitivity was 81.8% and specificity was 85.7%.

Conclusion

DIVC is a reliable indicator of capacity responsiveness in mechanically ventilated post‐pneumonectomy patients.