using the lightouch ® (pv-hct) device to monitor real-time changes in hematocrit levels induced by...
TRANSCRIPT
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
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)
Blood Composition
http://commons.wikimedia.org/wiki/File:1901_Composition_of_Blood.jpg
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
The LighTouch® DeviceDetects 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)
EE and IE
Human TestingDone according to IRB protocol
Small sample size
Pressure induced changesValsalva maneuver: Blowing against a closed
orifice
Initial rise in pressure, subsequent fall, rise again
http://en.wikipedia.org/wiki/Valsalva_maneuver
Valsalva Maneuver
Temperature induced changes
Temperature changes vessel volumehot temperature = vasodilationcold 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/
Results
Results
Results
ConclusionThe 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
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
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.
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