Related Experiment Video

Updated: Feb 3, 2026

In Vivo Real-Time Study of Drug Effects on Carotid Blood Flow in the Ovine Fetus
11:59

In Vivo Real-Time Study of Drug Effects on Carotid Blood Flow in the Ovine Fetus

Published on: April 28, 2023

644

Corrected carotid flow time and passive leg raise as a measure of volume status

Ralphe Bou Chebl1, Jeffrey Wuhantu2, Shafeek Kiblawi3

  • 1Department of Emergency Medicine, Ben Taub Hospital, Baylor College of Medicine, Houston, TX, United States of America; Department of Emergency Medicine, American University of Beirut, Beirut, Lebanon.

The American Journal of Emergency Medicine
|October 28, 2018
PubMed

Insights

Corrected carotid flow time (FTc) measured with passive leg raise (PLR) can non-invasively assess fluid volume in end-stage renal disease (ESRD) patients undergoing hemodialysis. This method shows promise for monitoring volume status in this population.

Area of Science:

  • Cardiovascular Physiology
  • Nephrology
  • Medical Ultrasound

Background:

  • End-stage renal disease (ESRD) patients often experience fluid volume overload or depletion, complicating management.
  • Accurate assessment of volume status is crucial for effective hemodialysis treatment and patient outcomes.

Purpose of the Study:

  • To evaluate the utility of corrected carotid flow time (FTc) combined with passive leg raise (PLR) as a non-invasive indicator of fluid volume status in ESRD patients.
  • To determine if FTc changes correlate with fluid removal during hemodialysis.

Main Methods:

  • A prospective observational study involving 54 ESRD patients requiring hemodialysis.
  • Common carotid artery flow time was measured using ultrasound before and after hemodialysis, and before and after PLR.
  • FTc was calculated and analyzed in relation to fluid volume removed and presence of congestive heart failure (CHF).

Main Results:

  • Mean FTc decreased significantly after hemodialysis (302.48 ms pre-PLR vs. 340.49 ms post-PLR), indicating fluid removal.
  • The magnitude of FTc decrease correlated with the volume of fluid removed during hemodialysis.
  • FTc changes after PLR showed a trend towards reflecting volume status, with a mean decrease of 19.15 ms for <3 L removed and 41.17 ms for >4 L removed.

Conclusions:

  • Corrected carotid flow time (FTc) in conjunction with passive leg raise (PLR) appears to be a valuable, non-invasive tool for assessing volume status in hemodialysis patients.
  • This technique may aid clinicians in optimizing fluid management for ESRD patients.
Abstract

Keywords:
CarotidFlow timeHemodialysisPassive leg raiseResponsivenessShockVolume status

More Related Videos

Author Spotlight: Assessing the Reliability of Doppler Ultrasound in Measuring Leg Blood Flow09:18

Author Spotlight: Assessing the Reliability of Doppler Ultrasound in Measuring Leg Blood Flow

Published on: December 15, 2023

3.5K
A Model of Disturbed Flow-Induced Atherosclerosis in Mouse Carotid Artery by Partial Ligation and a Simple Method of RNA Isolation from Carotid Endothelium11:00

A Model of Disturbed Flow-Induced Atherosclerosis in Mouse Carotid Artery by Partial Ligation and a Simple Method of RNA Isolation from Carotid Endothelium

Published on: June 22, 2010

29.9K

Related Concept Videos

Muscles that Move the Leg01:23

Muscles that Move the Leg

The movement of the legs is facilitated by numerous muscles located within the anterior, medial, and posterior compartments of the thigh.
Anterior Compartment
The quadriceps femoris, the most visible muscle of the anterior compartment, is integral for leg extension and thigh flexion. It is formed by merging four distinct muscles — the vastus lateralis, vastus medialis, vastus intermedius, and rectus femoris. The quadriceps tendon, a shared tendon of the four quadriceps muscles, is affixed...
5.3K
Distance Corrections01:15

Distance Corrections

To achieve precise distance measurements, especially in surveying and construction, certain corrections must be applied to account for potential sources of error like the standardization errors, temperature variations, and slope adjustments.Standardization error emerges when measurement equipment undergoes changes, such as wear, repairs, or weather impacts. To address this, surveyors compare the equipment’s readings to a standard. This process identifies any deviation that might lead to...
290
Power Factor Correction01:20

Power Factor Correction

The power transmission to a factory involves the transfer of apparent power, a combination of active and reactive power. The power factor measures how effectively electrical power is converted into useful work output. The ratio of the real power (KW) that does the work to the apparent power (KVA) supplied to the circuit.
539
Passive Filters01:27

Passive Filters

Passive filters are utilized to shape the frequency spectrum of signals across a diverse array of applications. These filters, using only passive elements like resistors (R), inductors (L), and capacitors (C), are capable of selectively allowing or blocking certain frequency ranges without the need for external power sources.
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff...
1.0K
Active versus Passive Immunity01:31

Active versus Passive Immunity

Immunity, along with the ability to limit pathogen growth to prevent significant body tissue damage, can be gained either by (1) actively developing an immune response within the individual after exposure to a pathogen or after getting vaccinated or (2) passively transferring immune components from an immune individual to one who is nonimmune. Both these forms of immunity can be found naturally and in medical practices.
Active Immunity
Active immunity refers to the resistance one develops...
10.8K
Marcia's Theory of Identity Status01:26

Marcia's Theory of Identity Status

James Marcia's identity status model provides a framework for understanding how adolescents navigate identity formation through varying degrees of exploration and commitment. Marcia's model builds on Erik Erikson's theories of psychosocial development, focusing specifically on how adolescents reconcile individual aspirations with societal expectations. His model describes identity formation as a dynamic process where adolescents move between different states depending on their level...
1.6K