Diagnostic Value of the Variations in Internal Jugular Vein Diameter and Blood Flow Rate in Patients with Intestinal Obstruction

The objective of the study is to explore the use of internal jugular vein diameter, respiratory variability, and blood flow velocity in predicting blood volume of patients with intestinal obstruction. A total of sixty patients with acute intestinal obstruction who were admitted to our hospital from June 2019 to June 2021 were included and including 33 males and 27 females. The patients were graded ASA I to III on the basis of their physical condition. Using the random number table method, the patients were divided into the inferior vena cava (IVC) and internal jugular vein (IJV) groups. The maximum diameter (D_max) and the minimum diameter (D_min) of the IVC and IJV groups were measured by M-type ultrasound, and the respiratory variation index (RVI) was calculated. The maximum blood flow velocity (BV_max) and the minimum blood flow velocity (BV_min) of each vessel were also measured in the respective groups by Doppler ultrasound, and the blood flow variation index (BVI) was calculated. Each patient was then infused with 5 ml/kg crystalloid solution, and the above parameters were measured again and compared to the respective pre-infusion values. The correlation between each measurement index and CVP and their ability to predict CVP > 6 mmHg were statistically evaluated. The RVI of IVC decreased significantly post-infusion (P = 0.018). Compared to the pre-infusion values, the D_min of IJV increased (P = 0.042), while the RVI and BVI decreased significantly after infusion (P = 0.004 and P = 0.047). The relevant measurement data could not be obtained for one patient in the IVC group due to obvious intestinal pneumatosis. There was a positive correlation between the D_min of IVC and CVP (pre-infusion R = 0.684 and P = 0.000; post-infusion R = 0.442 and P = 0.016), and a negative correlation between RVI and CVP (pre-infusion R =  − 0.826 and P = 0.000; post-infusion R =  − 0.663 and P = 0.000) before and after infusion. In addition, CVP was positively correlated to the D_min, BV_max, and BV_min of IJV before and after infusion (pre-infusion R = 0.652, 0.655, 0.795, and all P = 0.000; post-infusion R = 0.571, 0.586, 0.684, and P = 0.001, 0.001, and 0.000), and negatively with RVI and BVI (pre-infusion R =  − 0.808, − 0.677, and all P = 0.000; post-infusion R =  − 0.589, − 0.592, and all P = 0.001). The specificity of the D_min of IVC was 92.9%, and the sensitivity of RVI was 100% prior to the infusion, the post-infusion RVI could predict the blood volume with 100% sensitivity. In contrast, all indices of IJV except D_max predicted the blood volume before and after infusion. The area under the curve of RVI was the largest, indicating the highest predictive accuracy. The sensitivity and specificity of RVI were, respectively, 100 and 93.3% before infusion and 88.9 and 95.2% after infusion. The ultrasonically measured variability in the diameter and blood flow velocity of IJV can be used to predict the blood volume of patients with intestinal obstruction and has higher accuracy compared to the indices of IVC.