Point-of-care ultrasound—a new option for early quantitative diagnosis of pulmonary edema

Abstract

To investigate the value of point-of-care ultrasound (POCUS) in the early assessment of the severity of pulmonary edema in rabbits. A rabbit oleic acid (OA)-induced pulmonary edema model was used. 32 New Zealand rabbits were randomly divided into four groups: a control group and three pulmonary edema groups (mild, moderate, and severe). The features of transthoracic B-line artifacts (BLA-tt), blood pH, PaO2 and PaCO2, serum inflammatory factors, lung coefficient (LC), lung wet to dry weight ratio (W/D) and lung histopathology were assessed. BLA-tt features and severity of pulmonary edema were semi-quantitatively scored. The correlation between the number of BLA-tt and PaO2 and PaCO2 serum inflammatory factors, LC, and W/D were analyzed. An additional eight rabbits with severe pulmonary edema were used as the verified group, in which the lung was divided into BLA-ev-free and BLA-ev-clustered subregions by ex vivo lung ultrasound. The lung specimens were collected from each subregion for histopathological examination. The relationship between the features of BLA-ev and the lung histopathological abnormalities was analyzed. The number of BLA-tt, the levels of TNF-a, IL-1b, IL-6, and IL-8, LC, and W/D all increased, lung pathology was aggravated, and the appearance time of BLA-tt, pH, PaO2, and PaCO2 decreased dose-dependently on OA (p