Download presentation
Presentation is loading. Please wait.
Published byAmos Harvey Modified over 9 years ago
1
Using the LighTouch ® (Pv-Hct) device to monitor real-time changes in hematocrit levels induced by the Valsalva maneuver, vasodilation, and vasoconstriction Adil Naweed Afridi P. Dent, R. McDonough, S. Ortiz, J. Chaiken, J. Goodisman Syracuse University, Chemistry Department, Syracuse NY 13210
2
A thought… The leading preventable cause of death worldwide among men and women, civilians and soldiers, between ages 18-47 is undetected internal bleeding (Deng et. al) Autonomic compensation makes detection more difficult when there isn't an externally visible physical injury A leading indicator of internal bleeding is a loss in blood hematocrit (Hct) and an increase in plasma volume (Pv) B. Deng, E. Kastnerc, S. Narsipurc, J. Goodisman, and J. Chaiken, Proceedings of SPIE. Vol. 8935, 89351N-1 (2014)
3
Blood Composition http://commons.wikimedia.org/wiki/File:1901_Composition_of_Blood.jpg
4
Objective To detect real-time changes in blood Hct using the LighTouch ® (Pv-Hct) device under 3 conditions: (1) Valsalva maneuver (2) Vasodilation (3) Vasoconstriction Hct and plasma volumes were detected non-invasively in vivo in response to pressure and thermal stimuli
5
The LighTouch ® Device Detects changes in capillary blood Device uses 830 nm (NIR) laser light RBCs scatters light (EE) without a wavelength shift RBCs and plasma cause fluorescence and Raman (IE)
6
EE and IE
10
Human Testing Done according to IRB protocol Small sample size
11
Pressure induced changes Valsalva maneuver: Blowing against a closed orifice Initial rise in pressure, subsequent fall, rise again http://en.wikipedia.org/wiki/Valsalva_maneuver
12
Valsalva Maneuver
13
Temperature induced changes Temperature changes vessel volume hot temperature = vasodilation cold temperature = vasoconstriction For a given vessel, vasodilation is known to decrease Hct For a given vessel, vasoconstriction is known to increase Hct https://www.physicool.co.uk/physicool-hunting-response/
14
Results
17
Conclusion The Valsalva maneuver (pressure) stimulus was detected by the LighTouch ® device to fluctuate Hct Both hot and cold stimuli were detected by the LighTouch ® to create changes in Hct The LighTouch ® device detected a decrease in Hct during vasodilation (hot) stimulus The LighTouch ® device detected an increase in Hct during vasoconstriction (cold) stimulus All results are constant with previously accepted results
18
Acknowledgement REU and LSAMP Syracuse University Chemistry Department Dr. Joseph Chaiken Dr. Jerry Goodisman Tamara Hamilton Paul Dent Richard McDonough Steven Ortiz LSMCE Conference 2014
19
References J. Chaiken, J., et al., Simultaneous, noninvasive observation of elastic scattering, fluorescence and inelastic scattering as a monitor of blood flow and hematocrit in human fingertip capillary beds. J Biomed Opt, 2009. 14(5): p. 050505. J. Chaiken, J.Goodisman., On probing human fingertips in vivo using near infrared light: model calculations. 2009. [7]. Chaiken, J., et al. Noninvasive in vivo tissue and pulse modulated Raman spectroscopy of human capillary blood and plasma. Proc. SPIE, 2006, Vol 6093, 609305-1. Chaiken, J., et al. Noninvasive in-vivo tissue-modulated near-infrared vibrational spectroscopic study of mobile and static tissues: blood chemistry. Proc. SPIE, 2000, Vol 3918, 135-143. J. Chaiken, W. Finney, P. Knudson, K. Peter- son, C. Peterson, X. Yang, and R. Weinstock, ‘‘Noninvasive blood analysis by tissue modulated NIR Raman spectroscopy,’’ Proc. SPIE 4368, 134–145,2001.
20
Question?
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.