Comparison of muscle near infrared spectroscopy and femoral blood
gases during steady-state exercise in human.
Costes, Fr[acute]ed[acute]eric, Jean-Claude Barth[acute]el[acute]emy,
L[acute]eonard F[acute]easson, Thierry Busso, Andr[acute]e Geyssant,
Christian Denis.
Laboratoire de Physiologie - GIP Exercice, Facult[acute]e de
M[acute]edecine Jacques Lisfranc, Universit[acute]e Jean Monnet
Saint-[acute]etienne, France
APStracts 2:0523A, 1995.
Near InfraRed Spectroscopy (NIRS) is a non-invasive way of measuring
muscular oxygenation. We evaluated the relationship between NIRS
signal (IR-SmO2) and the femoral venous oxygen saturation (SfvO2)
during cycling exercise. Six healthy subjects performed a 30 minute
steady-state exercise at 80% max, in normoxia and hypoxia (FIO2 =
0.105). IR-SmO2 was recorded continuously throughout the tests with
the NIRS probe located on the vastus lateralis. Blood samples were
withdrawn every 5 minutes during exercise from radial artery and
femoral vein catheters. In normoxia, IR-SmO2 initiated a transient
non significant decrease at 5 minutes then returned to pre-exercise
level, whereas SfvO2 showed a fast decrease reaching 18% saturation
at 10 minutes without further change. By contrast, in hypoxia, IR
-SmO2 and SfvO2 demonstrated a parallel decrease then stabilized at 10
minutes. We conclude IR-SmO2 appears to parallel SfvO2 when both the
arterial and venous oxygen contents decrease during steady-state
exercise in hypoxia while it does not follow SfvO2 change in
normoxia.
Received 22 May 1995; accepted in final form 15 November 1995.
APS Manuscript Number A534-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 8 December 95