Clinical Trial: Ultrasound Measurement of Reactive Hyperemia in Critical Care

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Observational

Official Title: Ultrasound Measurement of Reactive Hyperemia in Critical Care: Prognostic and Pathophysiologic Significance

Brief Summary:

The investigators hypothesize that doctors and nurses can undergo a brief period of training and then use ultrasound to accurately measure blood flow in a forearm artery after a brief period when this flow is interrupted with a blood pressure cuff, a measurement the investigators call reactive hyperemia. Reactive hyperemia indicates whether the small blood vessels in the body are healthy -- lower reactive hyperemia indicates worse small blood vessel function. When measured by experienced ultrasound experts, low reactive hyperemia strongly predicts death in critically ill patients with infection (severe sepsis).

The investigators are conducting this study to determine if doctors and nurses, without specific pre-existing expertise in ultrasound, can be trained to make these measurements accurately. If so, the investigators will prove that these measurements can be applied reliably in real-world practice.

The investigators also hypothesize that reactive hyperemia predict the outcomes of illness not just in patients with severe infection, but in other critically ill patients as well.

Finally, the investigators hypothesize that reduced blood flow after blood pressure cuff occlusion is linked with other abnormalities of blood, previously identified in critically ill patients. For example, red blood cells from patients with severe sepsis have been shown to be stiffer than normal, so they are less able to flow along the small blood vessel passages of the body. Red blood cells become stiffer when there is a certain type of stress in the body known as "oxidative stress."

If the investigators show that low reactive hyperemia, stiff red blood cells, and oxidative stress are linked, the investigators hope to develop new treatme

Detailed Summary:
Sponsor: University of Rochester

Current Primary Outcome: hospital mortality [ Time Frame: vital status at hospital discharge, an expected average of 3 weeks ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

Original Secondary Outcome:

Information By: University of Rochester

Dates:
Date Received: July 6, 2012
Date Started: January 2013
Date Completion: July 2018
Last Updated: August 26, 2016
Last Verified: August 2016