Systemic and subcutaneous microvascular oxygen tension dissociation during 4-hour hemorrhagic shock in conscious hamsters. Kerger, Heinz, Darin J. Saltzman, Michael D. Menger, Konrad Messmer, and Marcos Intaglietta. Department of Bioengineering, University of California San Diego, La Jolla, CA 92093-0412, Institute for Clinical-Experimental Surgery, University of Saarland, Homburg, Germany, Institute for Surgical Research, Ludwig-Maximilians-University, Munich, Germany
APStracts 2:0366H, 1995.
The relationship between systemic and microvascular pO2 in subcutaneous connective tissue and hemodynamics was investigated during 4-hour hemorrhagic shock (40 mm Hg) in conscious Syrian golden hamsters (n = 66) fitted with a dorsal skinfold window. Systemic blood gases, metabolic parameters, arteriolar, venular and tissue pO2, microvascular red blood cell velocity (RBC[PHI]) and blood flow were evaluated in survivors (S) and non-survivors (NS). Surviving animals were resuscitated with shed blood. Microvascular and tissue pO2 were measured by phosphorescence decay of Pd-meso-tetra porphyrin (30 mg/kg b.w. i.v.). Shock caused a significant dissociation between systemic arterial and microvascular arteriolar pO2 levels. Arterial pO2 increased from 59.7 +/- 12.0 to 110.8 +/- 19.7 mm Hg (S) and from 64.0 +/- 13.7 to 128.5 +/- 10.1 mm Hg (NS), while pO2 in large arterioles decreased from 56.9 +/- 5.5 (control) to 29.5 +/- 20.1 (S) and 6.0 +/- 5.7 (NS). Correspondingly tissue pO2 fell from 24.1 +/- 6.8 (control) to 0.9 +/- 0.6 (S) and 0.4 +/- 0.3 (NS) mm Hg. Venous pO2 decreased from 28.8 +/- 3.7 to 20.4 +/- 4.1 (S) and from 28.0 +/- 2.9 to 16.3 +/- 0.5 (NS) mm Hg. Shock outcome and tissue oxygenation were predicted by arterial blood gases, metabolic and microcirculatory conditions, but not by central venous pO2. 

Received 11 May 1995; accepted in final form 3 August 1995.
APS Manuscript Number H451-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 24 August 1995.