Related Experiment Video
Updated: Jul 9, 2026

Continuous Venous-Arterial Doppler Ultrasound During a Preload Challenge
Published on: January 20, 2023
Renal and carotid vascular resistance assessed with Doppler sonography
Yuko Ohta1, Koji Fujii, Setsuro Ibayashi
1Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
Purpose:
Resistance index (RI) is widely used for the evaluation of circulatory resistance and atherosclerosis with Doppler sonography, but differences in RI among vascular beds have not been fully elucidated. The present study was designed to evaluate the relationship between renal and carotid artery RI and to compare their relative risk factors for an increase in RI.
Methods:
One hundred eighty-five inpatients who underwent sonographic assessment of the renal and carotid arteries were enrolled in the study.
Results:
Multivariate analyses revealed that age, pulse pressure (PP), and serum glucose level were positively correlated, whereas diastolic blood pressure (DBP) and creatinine clearance were negatively correlated with the RI of the interlobar arteries. Sex (male) and PP correlated positively, whereas DBP correlated negatively with the RI of the common carotid artery (CCA). The RI of the interlobar arteries was positively associated with that of the CCA, even after adjustment for major cardiovascular risk factors.
Conclusions:
These findings suggest that RI of the renal and carotid arteries increase in parallel to a certain extent. On the other hand, risk factors for the increase of RI of the carotid and renal arteries differed in part, suggesting that specific control of respective risk factors may also be needed to prevent vascular damage in each vascular bed.
Related Concept Videos
Vascular Resistance
The primary determinants of vascular resistance are vessel diameter, blood viscosity, and vessel length. Among these, vessel diameter plays the most significant role due to the fourth power relationship described by...
Assessing Blood pressure using a doppler ultrasound
Pre-Procedural Guidelines for Doppler Ultrasound Blood Pressure Assessment:
Preparation of Equipment:
Peripheral Arterial Disease II: Clinical Manifestations and Diagnostic Evaluation
Equipments Used To Measure Blood Pressure
This invasive approach involves cannulating a peripheral artery. During each cardiac contraction, pressure generates mechanical motion within the catheter, transmitted through rigid, fluid-filled tubing to a transducer. This transducer converts mechanical motion into electrical signals displayed as waveforms on a monitor. An automatic flushing system prevents blood backflow. Due to the potential risk of unexpected arterial blood loss, this method is primarily used in intensive...
