Figure 1
(A) Pleural line (vertical arrows indicate the bat sign, with ribs and pleural line). One A-line at the standardized location (horizontal arrows). (B) B-lines. 6 B-lines visible between two ribs in short-axis. (C) BLUE-points. The BLUE-protocol uses three points per lung. Two hands are applied this way, against the clavicule. Two points are anterior, the upper-BLUE-point (middle of upper hand, that is, roughly, second intercostal space between parasternal and anterior axillary line) and the lower-BLUE-point (middle of lower palm). One point, continuing transversally the lower BLUE-point as «posterior as possible, is the posterolateral alveolar pleural syndrome-point» (PLAPS-point). Note that the PLAPS-point seems rather cranial, but is in actual fact just a bit above the diaphragm usually. (D) The lateral point. For adapting the approach to the perioperative setting with its constraints in this study, we took a clinically accessible lateral point located transversally between lower BLUE-point and PLAPS-point, and longitudinally between anterior and posterior axillary line. Note that, if a theoretical point is not accessible for any reason, device or other, the BLUE-points are flexible up to a large tolerance (indicated by the areas in the cartouche).
