Severe pleural restriction: the maximum static pulmonary recoil pressure as an acid in diagnosis.

Three patients with pleural restriction are presented in detail. One patient had had a right pneumonectomy and died of ventilatory failure due to left-sided restrictive pleurisy. The second patient had neoplastic pleural effusion and inactive tuberculosis. The third patient had systemic lupus erythematosus with bilateral restrictive pleuritis. The physiologic picture was similar in the three cases, with marked decrease of lung volumes, increase of the RV/TLC ratio, absence of airways obstruction, decrease of the Dco and decrease of dynamic lung compliance. In addition, each of these three patients and others with severe pleural restriction had a lower than normal maximum static pulmonary recoil pressure (Pmax). Since in pulmonary restrictive disease, the Pmax was found to be elevated, it was a useful test for distinguishing pulmonary restriction from pleural restriction.