Measuring the ratio of femoral vein diameter to femoral artery diameter by ultrasound to estimate volume status

• Published in: BMC Cardiovascular Disorders 2021, Vol.21 (1)
• Main Authors: Ma, Zhihang, Gai, Jiaxin, Sun, Yinghan, Bai, Yunpeng, Cai, Hongyi, Wu, Lei, Sun, Lixiu, Liu, Junyan, Xue, Li, Liu, Bingchen
• Format: Report
• Language: English
• Subjects: Blood; Diagnosis, Ultrasonic; Femoral artery; Measurement; Medical examination; Veins; Venous pressure
• ISSN: 1471-2261; 1471-2261
• DOI: 10.1186/s12872-021-02309-7

Background Currently, the accepted effective method for assessing blood volume status, such as measuring central venous pressure (CVP) and mean pulmonary artery pressure (mPAP), is invasive. The purpose of this study was to explore the feasibility and validity of the ratio of the femoral vein diameter (FVD) to the femoral artery diameter (FAD) for predicting CVP and mPAP and to calculate the cut-off value for the FVD/FAD ratio to help judge a patient's fluid volume status. Methods In this study, 130 patients were divided into two groups: in group A, the FVD, FAD, and CVP were measured, and in group B, the FVD, FAD, and mPAP were measured. We measured the FVD and FAD by ultrasound. We monitored CVP by a central venous catheter and mPAP by a Swan-Ganz floating catheter. Pearson correlation coefficients were calculated. The best cut-off value for the FVD/FAD ratio for predicting CVP and mPAP was obtained according to the receiver operating characteristic (ROC) curve. Results The FVD/FAD ratio was strongly correlated with CVP (R = 0.87, P < 0.0000) and mPAP (R = 0.73, P < 0.0000). According to the ROC curve, an FVD/FAD ratio [greater than or equai to] 1.495 had the best test characteristics to predict a CVP [greater than or equai to] 12 cmH.sub.2O, and an FVD/FAD ratio [less than or equai to] 1.467 had the best test characteristics to predict a CVP [less than or equai to] 10 cmH.sub.2O. An FVD/FAD ratio [greater than or equai to] 2.03 had the best test characteristics to predict an mPAP [greater than or equai to] 25 mmHg. According to the simple linear regression curve of the FVD/FAD ratio and CVP, when the predicted CVP [less than or equai to] 5 cmH.sub.2O, the FVD/FAD ratio was [less than or equai to] 0.854. Conclusion In this study, the measurement of the FVD/FAD ratio obtained via ultrasound was strongly correlated with CVP and mPAP, providing a non-invasive method for quickly and reliably assessing blood volume status and providing good clinical support. Keywords: Femoral vein diameter, Femoral artery diameter, CVP, mPAP, Volume status, Pulmonary hypertension