NPPB and hydrops fetalis: The results of this study can be summarized as follows: (1) serum levels of NT–proBNP are not influenced by tidal volume size in patients without ARDS at onset of mechanical ventilation; (2) serum levels of NT–proBNP are dependent on the development of ARDS; and (3) serum levels of NT–proBNP are dependent on cumulative fluid balances, both in patients with and without HF, and on development of AKI.