||What is Happening in The Ards Piglet Lungs: - The Origin of B-Lines on Ultrasonography -
NIshimura, Masayuki ,
Tsubo, ToshihitoHirota, Kazuyoshi
22 , 2017-10-05 , 弘前大学大学院医学研究科・弘前医学会
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 inARDS 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） andtransesophageal 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 sectionswere examined by light microscopy.Results: Following the saline infusion into the pleural space, we observed B-lines fanning out from the visceralpleura. As pulmonary consolidation developed, B-lines disappeared. The structure that B-lines fanned out from wasthe complex of thickened pleura and sub-pleural interlobular septa surrounded by gas. In the tissue where B-linesdisappeared, 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 septasurrounded by gas. B-lines disappeared when the sub-pleural thickened interlobular septa were surrounded by cells and liquid.