Po2 measurements in the rat intestinal microcirculation.
Sinaasappel, M., C. Donkersloot, J. Van Bommel, and C. Ince.
Department of Anesthesiology, Academic Medical Center, University
of Amsterdam, Meibergdreef 9,1105 AZ Amsterdam, The Netherlands.
Phone 31-20-5665242, Fax 31-20-6979004, email
APStracts 6:0059G, 1999.
Microvascular partial oxygen pressure (Po2) data measured with the
quenched phosphorescence of Pd-porphine with optical fibers has
provided new insight into the behavior of the microvascular
oxygenation in models of shock. However, the actual microcirculatory
compartment measured by this fiber technique has not yet been
demonstrated. The purpose of this study was to investigate whether
the Po2 of the intestines, as measured using a fiber phosphorimeter,
reflects the microvascular compartment. To this end, a new intravital
phosphorimeter with an improved sensitivity for high Po2 levels (up
to 180 mmHg) was developed and validated. With this set-up Po2 values
were measured at different inspired oxygen fractions (15, 25 and 50%
O2) in first order arterioles, capillaries and venules of the ileum
of rats. Simultaneously the Po2 was measured with an optical fiber
attached to another phosphorimeter. The correlation of the PO2 in the
capillaries and 1V vessels with fiber optic measurements show
excellent correlation (R2 = 0.94 slope 0.99). We therefore conclude
that values measured with the fiber phosphorimeter correlate with the
capillary and venular Po2.
Received 25 August 1998; accepted in final form 25 February 1999.
APS Manuscript Number G344-8.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
ISSN 1080-4757 Copyright 1999 The American Physiological Society.
Published in APStracts on 5 March 1999