The effects of short-term endotoxemia and dopamine on mucosal oxygenation in the porcine jejunum. Hasibeder, Walter, Reinhard Germann, Hans Joachim Wolf, Markus Haisjackl, Hans Hausdorfer, Bernhard Riedmann, Johannes Bonatti, Eva Gruber, Birgit Schwarz, Peter Waldenberger, Barbara Friesenecker, and Bernhard Furtner. Department of Anesthesia and Intensive Care Medicine, Institute for Histology and Embryology, Institute for Bacteriology, First Department of Surgery, and Department of Radiology $, University of Innsbruck, A-6020 Innsbruck, Austria
APStracts 2:0220G, 1995.
Effects of Escherichia Coli lipopolysaccharide (2 [mu]g /(kg*20min); LPS), given sytemically (S) or via superior mesenteric artery (M) and consecutive dopamine infusion (16 [mu]g/(kg*min)) on jejunal mucosal (PO2muc) and serosal (PO2ser) tissue oxygen tension (Clark-type surface electrodes) and jejunal mucosal microvascular hemoglobin oxygen saturation (HBO2muc; tissue reflectance spectrophotometry) were investigated in a hemodynamically stable pig model. 21 pigs were anesthetized, paralyzed and mechanically ventilated. Following laparotomy, a mesenteric venous catheter was inserted and a jejunal antimesenteric enterotomy performed. LPS infused animals developed similar degrees of pulmonary hypertension. No differences in cardiac output and mean arterial blood pressure between groups were found. PO2muc and HBO2muc were significantly lower in M animals compared to control (C) (210min: PO2muc: 7.12 + 1.81 (M); 19.01 + 3.12 (C) mmHg; HBO2muc: 28.78 + 3.36 (M); 49.09 + 3.84% (C)), while S animals ranged in between (PO2muc: 13.36 + 2.2 mmHg; HBO2muc: 40.68 + 4.43%). 12.6% (C), 20.6% (S), and 46.3% (M) of measured PO2muc values ranged from 0-5 mmHg. PO2ser was lower in LPS animals compared to control (59.43 + 5.4 (C); 45.00 + 6.12 (S); 47.33 + 4.34 (M) mmHg). Dopamine increased PO2muc and HBO2muc to similar absolute values and significantly decreased frequency of PO2muc (0-5 mmHg) in M animals. We conclude that LPS impairs mucosal tissue oxygenation independently of systemic hemodynamics. Mucosal microvascular dysfunction depends on regional LPS concentrations. Under conditions of compromised tissue oxygenation, dopamine significantly improves PO2muc and HBO2muc.

Received 7 August 1995; accepted in final form 5 October 1995.
APS Manuscript Number G338-5.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 November 95