Pulmonary infections of gut origin after major liver resection in rats.

OBJECTIVE

To assess the incidence of translocation of enteric bacteria to the lungs in the early postoperative period (1, 2, 4, and 6 hours) after sham operation, 70% hepatectomy, and 90% hepatectomy.

DESIGN

Randomised laboratory experiment.

SETTING

University department.

MATERIAL

96 Adult male Sprague-Dawley rats.

INTERVENTIONS

Sham operation (n = 24), 70% hepatectomy (n = 36), and 90% hepatectomy (n = 36). Injection of 1 ml (1.5 x 10(7) cpm/rat) 125I-labelled heat-killed Escherichia coli 15 minutes before the animals were killed.

MAIN OUTCOME MEASURES

Arterial blood gas analyses, wet: dry weight ratio of lungs, and measurements of pulmonary isotopic flux (amount of 125I radioactivity in the lungs compared with that in the blood) 1, 2, 4, and 6 hours after operation. Quantitative microbiology of lungs.

RESULTS

There was no pulmonary oedema in those rats that underwent sham operation. Pulmonary oedema had developed by 6 hours after 70% hepatectomy and by 2 hours after 90% hepatectomy. The lung:blood ratio of 125I-labelled bacteria increased as the pulmonary oedema developed, but pulmonary oxygen exchange was not influenced during the first 6 hours after hepatectomy. The incidence of bacterial translocation increased with the extent of hepatectomy and with the length of time after operation.

CONCLUSION

Bacterial translocation from the gut could lead to pulmonary infection after major liver resection in rats.