It is not possible to measure blood flow with the InSpectraTMStO2 Tissue Oxygenation Monitor. However, you can get an indication of the amount of blood in the tissue bed by looking at tissue hemoglobin index (THI).
The physiological significance of StO2 is derived from the interplay between flow (delivery) and O2 consumption (demand). Low THI combined with low StO2 values may indicate a flow problem (e.g. in shock states).
Evidence to support response:
DeBlasi RA, Palmisani S, Alampi D, Mercieri M, Romao R, Collini S, Pinto G. Microvascular dysfunction and skeletal muscle oxygenation assessed by phase-modulation near-infrared spectroscopy in patients with septic shock. Int Care Med. 2005:31:1661-1668.
DeBlasi RA, Ferrari M, Natali A, Cont G, Mega A, Gasparetto A. Nonivasive measurement of forearm blood flow and oxygen consumption by near infrared spectroscopy. J Appl Physiol. 1994;76(3):1388-1393.
Carollo T, Creuteur J, DeBacker D, Vincent JL. Microvascular response to reactive hyperemia is altered in septic patients. 2004 Conference, European Society of Intensive Care Medicine.
Carollo T, Creuteur J, DeBacker D, Vincent JL. Persistent altered microvascular reactivity is predictive of mortality in septic patients. 2004 Conference, European Society of Intensive Care Medicine.
Pareznik R, Knezevic R, Voga G, Podbregar M. Changes in muscle tissue oxygenation during stagnant ischemia in septic patients. Int Care Med. 2006;32(1):87-92.
Skarda DE, Mulier KE, Myers DE, Taylor JH, Beilman GJ. Dynamic near-infrared spectroscopy measurements in patients with severe sepsis. Shock. 2007;27(4):348-353.
Torres A, Polanco P, Pinsky MR, Kim H, Puyana JC. Noninvasive real-time quantification of cardiovascular reserve in human circulatory shock. In press (2007).