Reliability, Laterality and the Effect of Respiration on the Measured Corrected Flow Time of the Carotid Arteries.
BACKGROUND
Corrected flow time (FTc) measured via sonography of the carotid artery is a novel method that has shown promising results for predicting fluid responsiveness in shock states. It is a rapid and noninvasive examination that can be taught to emergency physicians with ease. However, its reliability has not been assessed, and the effects of several variables, including respiration and side of evaluation, are unclear.


OBJECTIVES
The objectives were to compare carotid FTc during different phases of the respiratory cycle, (at end-inspiration and end-expiration), to compare FTc reproducibility among providers, and to compare FTc on the right and left sides in a given individual.


METHODS
The FTc of both the right and left carotid arteries was measured in 16 healthy volunteers during an inspiratory hold and an expiratory hold. Examinations were completed by three sonographers blinded to previous results and were analyzed for reliability and reproducibility.


RESULTS
Reliability and reproducibility were poor when comparing sonographers under all circumstances. No significant differences were found when comparing left vs. right sides of measurement regardless of respiratory phase.


CONCLUSION
Although this method for predicting fluid responsiveness has many promising aspects, reproducibility between sonographers was found to be poor. No significant difference was found between the two sides of the body or respiratory phase.
['Doctor|Michael|M|', 'Siadecki|Sebastian D|SD|', 'Cooper|Denrick|D|', 'Rose|Gabriel|G|', 'Drake|Aaran B|AB|', 'Ku|Melvin|M|', 'Suprun|Maria|M|', 'Saul|Turandot|T|']
D001783:Blood Flow Velocity D002339:Carotid Arteries D005260:Female D007839:Functional Laterality D006801:Humans D008297:Male D011446:Prospective Studies D015203:Reproducibility of Results D015656:Respiratory Mechanics D014463:Ultrasonography
corrected flow time carotid artery critical care ultrasound volume responsiveness