Abstract
Background
Point-of-care ultrasound is a fundamental tool in the emergency department when managing
the critically ill patient. Determining a patient's hemodynamic status at the bedside
can better guide resuscitation efforts. The left ventricular outflow tract velocity–time
integral (VTI) is a validated, noninvasive, and rapidly acquired echocardiographic
measurement that is analogous to stroke volume.
Discussion
VTI can be used to determine fluid responsiveness and to risk stratify patients, particularly
in pulmonary embolism, heart failure, and sepsis. Emergency physicians with limited
experience can successfully measure VTI in a timely and accurate manner. However,
VTI measurement is not commonly taught in emergency medicine residency and, as a result,
it is an underused tool.
Conclusions
VTI is an objective tool for clinicians to assess the hemodynamic status of critically
ill patients. Understanding the acquisition of VTI and proper application in the context
of the patient's history, clinical examination, and other bedside ultrasound findings,
should be reviewed within the emergency medicine residency ultrasound curriculum.
This article provides a simple four-step protocol, as well as bedside applications
and potential limitations for VTI in the ED.
Keywords
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Article Info
Publication History
Published online: April 30, 2022
Accepted:
April 23,
2022
Received in revised form:
February 11,
2022
Received:
November 20,
2021
Identification
Copyright
© 2022 Published by Elsevier Inc.
