Related Experiment Video

Updated: Apr 11, 2026

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research
08:42

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research

Published on: October 22, 2014

28.1K

A pilot study of the relationship between Doppler-estimated carotid and brachial artery flow and cardiac index

U Weber1, N J Glassford2, G M Eastwood2

  • 1Department of Intensive Care, Austin Hospital, Melbourne, Victoria, Australia.

Anaesthesia
|May 27, 2015
PubMed

Insights

Doppler ultrasound measurements of peripheral arterial blood flow in humans showed a weak correlation with cardiac index. These findings suggest that peripheral blood flow cannot reliably estimate cardiac index non-invasively.

Area of Science:

  • Cardiovascular Physiology
  • Medical Imaging
  • Diagnostic Ultrasound

Background:

  • Cardiac index is a critical measure of heart function.
  • Non-invasive methods for estimating cardiac index are highly sought after.
  • Doppler ultrasound is widely used for assessing blood flow.

Purpose of the Study:

  • To investigate the correlation between Doppler-estimated peripheral arterial blood flow (carotid and brachial arteries) and cardiac index in healthy human volunteers.
  • To determine if peripheral arterial blood flow can serve as a non-invasive surrogate for cardiac index.

Main Methods:

  • Doppler ultrasound was used to measure carotid and brachial artery blood flow in 11 human volunteers.
  • Measurements were correlated with simultaneously measured cardiac index.
  • Statistical analysis, including correlation coefficients (ρ), was employed.

Main Results:

  • Moderate to good correlations were observed between right- and left-sided brachial (ρ = 0.45) and carotid (ρ = 0.567) arterial blood flows.
  • Peripheral arterial blood flows (brachial and carotid) showed no or negative correlations with cardiac index (e.g., right brachial: ρ = -0.145; right carotid: ρ = -0.376).

Conclusions:

  • Doppler-estimated peripheral arterial blood flows exhibit only a weak correlation with cardiac index in humans.
  • Peripheral arterial blood flow measurements using Doppler ultrasound are not suitable for non-invasive estimation of cardiac index.
  • Findings contrast with some previous studies, highlighting the limitations of this non-invasive approach.

More Related Videos

Continuous Venous-Arterial Doppler Ultrasound During a Preload Challenge09:32

Continuous Venous-Arterial Doppler Ultrasound During a Preload Challenge

Published on: January 20, 2023

4.3K
A Methodological Approach to Non-invasive Assessments of Vascular Function and Morphology09:33

A Methodological Approach to Non-invasive Assessments of Vascular Function and Morphology

Published on: February 7, 2015

17.0K

Related Concept Videos

Assessing Blood pressure using a doppler ultrasound01:19

Assessing Blood pressure using a doppler ultrasound

To obtain accurate blood pressure measurements in clinical settings, especially when traditional methods are insufficient, healthcare professionals utilize the Doppler ultrasound technique. This method uses high-frequency sound waves to detect blood flow within the arteries, which is crucial for patients with conditions that complicate circulatory system assessment.
Pre-Procedural Guidelines for Doppler Ultrasound Blood Pressure Assessment:
Preparation of Equipment:
3.0K
Assessment of blood pressure in brachial artery(one-step method)01:15

Assessment of blood pressure in brachial artery(one-step method)

This procedural guide systematically measures blood pressure using an oscillometric digital sphygmomanometer, emphasizing accuracy, patient safety, and comfort.
Prepare for the Procedure:
1.4K
Assessment of blood pressure in brachial artery(two-step method)01:23

Assessment of blood pressure in brachial artery(two-step method)

Measuring blood pressure is a fundamental skill in healthcare that aids in diagnosing and monitoring hypertension and other cardiovascular conditions. An aneroid sphygmomanometer, commonly used in clinical settings, offers a manual and precise method for blood pressure measurement. The technique for using this instrument involves specific steps that must be carefully executed to ensure accuracy. The following detailed description outlines a two-step technique for assessing blood pressure using...
2.1K
Cardiac Output II: Effect of Stroke Volume on Cardiac Output01:22

Cardiac Output II: Effect of Stroke Volume on Cardiac Output

Cardiac output (CO), the amount of blood the heart pumps per minute, is a parameter in cardiovascular physiology determined by stroke volume and heart rate. Stroke volume, the amount of blood pushed from one of the ventricles per heartbeat, is influenced by preload, afterload, and contractility.
Preload
Preload refers to the initial elongation of the cardiac myocytes before contraction and is related to the volume of blood filling the heart at the end of diastole, or end-diastolic volume. The...
4.6K
Cardiac Output I:Effect of Heart Rate on Cardiac Output01:19

Cardiac Output I:Effect of Heart Rate on Cardiac Output

Cardiac Output
Cardiac output (CO) refers to the total amount of blood ejected by one of the ventricles in liters per minute (L/min). In a resting adult, CO ranges from 5 to 6 L/min, adjusting according to the body's metabolic requirements.
Effect of Heart Rate on Cardiac Output
Cardiac output adapts to metabolic demands during stress, physical activity, or illness. The autonomic nervous system regulates heart rate via the sinoatrial node. The parasympathetic nervous system decreases heart...
3.4K