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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