Phosgene has the characteristic odor of freshly mown grass. The threshold for detecting phosgene's characteristic odor is so close to the irritant threshold as to be useless as a warning. The individual's sense of dyspnea as the lung stiffens still serves as the best indicator of impending pulmonary edema. These symptoms may appear to be rather minor at first, resembling the symptoms of a common cold or anxiety reaction. Painful cough, frothy sputum, cyanosis, rales, dullness to percussion, and radiographic evidence support the diagnosis.
Uncomplicated cases recover without permanent after effects.
However, the possibility of secondary bacterial pulmonary infection is considerable. These gross observations may be helpful in mass casualty triage. In either case, do not release these personnel to duty without a careful re-examination of the chest. Treatment of non cardiac pulmonary edema in the field is mostly supportive, with enforced rest to minimize exertion. The risk of bronchopneumonia is greatest when pulmonary edema begins to subside.