Can Emergency Physicians Perform Common Carotid Doppler Flow Measurements to Assess Volume Responsiveness?
Abstract
Introduction: Common carotid flow measurements may be clinically useful to determine volumeresponsiveness. The objective of this study was to assess the ability of emergency physicians (EP)to obtain sonographic images and measurements of the common carotid artery velocity time integral(VTi) for potential use in assessing volume responsiveness in the clinical setting.
Methods: In this prospective observational study, we showed a five-minute instructional videodemonstrating a technique to obtain common carotid ultrasound images and measure the commoncarotid VTi to emergency medicine (EM) residents. Participants were then asked to image thecommon carotid artery and obtain VTi measurements. Expert sonographers observed participantsimaging in real time and recorded their performance on nine performance measures. An expertsonographer graded image quality. Participants were timed and answered questions regarding easeof examination and their confidence in obtaining the images.
Results: A total of 30 EM residents participated in this study and each performed the examinationtwice. Average time required to complete one examination was 2.9 minutes (95% CI [2.4-3.4 min]). Participants successfully completed all performance measures greater than 75% of the time, with theexception of obtaining measurements during systole, which was completed in 65% of examinations.Median resident overall confidence in accurately performing carotid VTi measurements was 3 (on ascale of 1 [not confident] to 5 [confident]).
Conclusion: EM residents at our institution learned the technique for obtaining common carotidartery Doppler flow measurements after viewing a brief instructional video. When assessed atperforming this examination, they completed several performance measures with greater than 75%success. No differences were found between novice and experienced groups. [West J Emerg Med.2015;16(2):255–259.]