A Carotid Doppler Patch Accurately Tracks Stroke Volume Changes During a Preload-Modifying Maneuver in Healthy Volunteers. (January 2020)

• Record Type: Journal Article
• Authors: Kenny, Jon-Émile S.; Barjaktarevic, Igor; Eibl, Andrew M.; Parrotta, Matthew; Long, Bradley F.; Eibl, Joseph K.; Michard, Frederic
• Is Part Of: Critical care explorations. Volume 2:Number 1(2020)
• Publication Date: 2020-01
• Subjects: carotid ultrasound -- corrected flow time -- fluid responsiveness -- stroke volume -- velocity time interval
• DOI: 10.1097/CCE.0000000000000072
• Languages: English
• ISSNs: 2639-8028

Abstract

Abstract : Objectives: Detecting instantaneous stroke volume change in response to altered cardiac preload is the physiologic foundation for determining preload responsiveness. Design: Proof-of-concept physiology study. Setting: Research simulation laboratory. Subjects: Twelve healthy volunteers. Interventions: A wireless continuous wave Doppler ultrasound patch was used to measure carotid velocity time integral and carotid corrected flow time during a squat maneuver. The Doppler patch measurements were compared with simultaneous stroke volume measurements obtained from a noninvasive cardiac output monitor. Measurements and Main Results: From stand to squat, stroke volume increased by 24% while carotid velocity time integral and carotid corrected flow time increased by 32% and 9%, respectively. From squat to stand, stroke volume decreased by 13%, while carotid velocity time integral and carotid corrected flow time decreased by 24% and 10%, respectively. Both changes in carotid velocity time integral and corrected flow time were closely correlated with changes in stroke volume ( r 2 = 0.81 and 0.62, respectively). The four-quadrant plot found a 100% concordance rate between changes in stroke volume and both changes in carotid velocity time integral and changes in corrected flow time. A change in carotid velocity time integral greater than 15% predicted a change in stroke volume greater than 10% with a sensitivity of 95% and a specificity of 92%. A change in carotid corrected flow time greater than 4% predicted a change in stroke volume greater than 10% with a sensitivity of 90% and a specificity of 92%. Conclusions: In healthy volunteers, both carotid velocity time integral and carotid corrected flow time measured by a wireless Doppler patch were useful to track changes in stroke volume induced by a preload-modifying maneuver with high sensitivity and specificity.