Gravitational Edema of the Lungs Observed During Assisted Respiration

¹ Department of Radiology, Beth Israel Hospital and Harvard Medical School, Boston; X-ray Department, Auckland Hospital, Auckland, New Zealand

The chest radiographs of 25 patients having treatment with intermittent positive pressure ventilation (IPPV) and showing evidence of intrapulmonary edema were studied to demonstrate a possible direct relationship between the position of the patient and the position of the edema. There was a statistically highly significant positive correlation, with 79.6 percent examples of gravity-dependent fluid. Intrapulmonary edema is just one form of intra-alveolar infiltration and it is important to be able to distinguish it from other forms such as inflammatory consolidation. The fact that edema will tend to become displaced as the patient moves from side to side is the criterion, thus providing a useful diagnostic test in which the patient is positioned so that a subsequent chest x-ray film will demonstrate displacement if there is a fluid infiltrate, but not otherwise.