Department of Anesthesiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
Intensive Care Unit, Hirosaki University Hospital Hirosaki, Japan
Department of Anesthesiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
抄録
B-lines are the important signs of pulmonary edema in acute respiratory distress syndrome
(ARDS) detected with ultrasonography. We studied the mechanism of the origin and disappearance of B-lines in
ARDS piglets using ultrasonography and microscopy.
Methods: ARDS was induced by intratracheal administration of 0.1M Hydrochloric Acid (HCl) in 23 anesthetized,
ventilated piglets. The occurrence of B-lines was evaluated using transthoracic echography (TTE) and
transesophageal echography (TEE). Changes in B-lines were recorded after a saline infusion into the pleural space,
and after pulmonary consolidation developed and reached the pleura. Left lower lobe was excised and lung sections
were examined by light microscopy.
Results: Following the saline infusion into the pleural space, we observed B-lines fanning out from the visceral
pleura. As pulmonary consolidation developed, B-lines disappeared. The structure that B-lines fanned out from was
the complex of thickened pleura and sub-pleural interlobular septa surrounded by gas. In the tissue where B-lines
disappeared, the thickened sub-pleural interlobular septa were surrounded by cells and liquid.
Conclusions: We found that B-lines derive from the complex of thickened pleura and sub-pleural interlobular septa
surrounded by gas. B-lines disappeared when the sub-pleural thickened interlobular septa were surrounded by cells and liquid.