['The study investigates the effect of airway instrumentation on the histopathology of the intestine, contribution of bacterial translocation, and whether oxygen supplementation may counteract the possible detrimental effects of this procedure.', 'Fifty-five Wistar rats were assigned to 3 groups. Group 1 served as control. Groups 2 and 3 underwent airway instrumentation. In addition, group 3 received oxygen supplementation during the procedure. Arterial blood gases were measured after the procedure. Samples of mesenteric lymph nodes ileum, cecum, spleen, liver, and blood were harvested for determination of bacterial growth after 24 hours. Ileum was evaluated histologically.', 'In group 2, the rats presented a decrease in oxygen saturation (90% +/- 0.3%, P < .0001), hypoxemia (PaO2, 73 +/- 1.5 mm Hg; P < .0001), and respiratory acidosis (pH 7.27 +/- 0.01; PaCO2, 48 +/- 1.5 mm Hg; P < .0001) after airway instrumentation. These rats also showed evidence of intestinal injury (P < .0001) and bacterial translocation to mesenteric lymph nodes in 10 of 20 rats compared with 0 of 15 in the controls (P = .004). In group 3, oxygen supplementation provided normal arterial blood gas parameters, and led to minimal histologic changes and bacterial translocation in only 1 of 20 rats, compared with group 2 (P < .0001 and P = .005, respectively).'] Does oxygen supplementation during airway instrumentation improve intestinal barrier dysfunction?