Regarding now the comments of Drs. Reissig and Kroegel on the normal lung surface, apart from patients without lung disease, this pattern can be seen in: (1) patients with asthma/COPD; (2) a “few cases of strictly central localized pneumonia” (this situation, which is theoretically possible, is unlikely to occur in critically ill patients, in whom 98.5% of consolidations are pleural-based2); and (3) a “few cases of strictly central localized PE [pulmonary embolism].” If “PE” means “infarction,” these cases are likely rare and not severe (as in the case of pneumonia mentioned above); therefore, they were not included in the BLUE-protocol. If “PE” means “embolism,” we do not agree with Drs. Reissig and Kroegel: the term “central” or “proximal,” precisely defines massive embolism. This second confusion comes from the fact that both types of patients (ie, patients with nonsevere vs severe PE) generate a normal anterior lung surface (ie, the A-profile), placing patients with severe PE in our decision tree for embolism.