thromboxane-b2 and Bacteroides-Infections

Acute respiratory failure in humans often follows extrathoracic sepsis. The purpose of this study was to determine the effect of repeated episodes of intra-abdominal sepsis over several weeks on the structure and function of rat lung. Intermittent peritonitis and a bacteremia of Escherichia coli and Bacteroides fragilis were produced by weekly intra-abdominal implants of gelatin capsules containing these organisms (3.0 +/- 1.0 X 10(7) and 5.0 +/- 1.0 X 10(7) colony-forming units/ml, respectively; mean +/- SEM). After 4 weeks alveolar walls were thickened and cellular with focal areas of alveolar space consolidation: circulating polymorphonuclear leukocytes were increased (12.2 +/- 1.2 to 19.9 +/- 2.0 X 10(3)/mm3; p less than 0.05), as were plasma levels of 6-keto-PGF1 alpha (0.56 +/- 0.08 to 1.02 +/- 0.18 ng/ml; p less than 0.01). After 8 weeks the capillary bed was dilated and the alveolar walls and ducts appeared less cellular but showed fibrosis: The WBC count had increased to 25.5 +/- 1.0 X 10(3) (p less than 0.01). After 4 or 8 weeks of intermittent sepsis there was no increase in the pulmonary artery pressure or vascular resistance or any change in arterial oxygen tension, plasma thromboxane beta 2 level, or platelet count. We conclude that repeated bouts of sepsis and bacteremia in the rat cause progressive injury to lung alveoli without evidence of altered blood gas tensions or pulmonary hemodynamics.

Topics: 6-Ketoprostaglandin F1 alpha; Abdomen; Abscess; Animals; Bacterial Infections; Bacteroides fragilis; Bacteroides Infections; Blood Cell Count; Capsules; Disease Models, Animal; Escherichia coli Infections; Hematocrit; Hemodynamics; Lung; Male; Rats; Rats, Inbred Strains; Respiratory Distress Syndrome; Thromboxane B2