Title: Should we add VTI at the bedside?

Posted: 3/8/2016 by Haney Mallemat, MD

The RUSH exam is a rapid way to identify the cause of shock using ultrasound. What's the RUSH exam? Click here
The RUSH exam does not include an assessment of volume responsiveness (VR), but a new article by Blaivas, Aguiar, and Blanco suggests that it should be.
VR has classically been assessed by determining the stroke volume before and after a passive leg raise or a fluid bolus. Click here for a video on how to calculate the stroke volume (skip to 21:30 in the video)
The authors claim that VR can further be simplified by not measuring the left ventricular outflow tract (LVOT) and only comparing changes in the velocity-time integral (VTI). The assumption is that the LVOT is constant and doesn't change in most circumstances; a change of VTI that is greater than 15% suggests that the patient is VR
Further validation is required to determine the degree of benefit to adding VTI to the RUSH exam, however measuring VTI is a skill that can be done with relatively little training and is clinically helpful.