Nitrous vapours are oxidants and they create fibrosing lesions in the
distal bronchioles and alveoli. The degree of oedema in the initial le
sion influences the development of acute respiratory failure and the p
rognosis in the initial term. We have seen a case of acute hypoxic int
erstitial pneumonia following accidental inhalation of nitrous vapours
with lesions of bronchiolitis obliterans. The outcome subsequently fo
llowed the usual pattern and there was a complete cure with steroid th
erapy.