Pulmonary function changes after large volume paracentesis.

Large volume paracentesis (LVP) is a safe, rapid, and effective treatment of ascites in cirrhotic patients. We investigated the effects of a 5-L aspiration of ascites on pulmonary function parameters in eight hemodynamically stable patients with cirrhosis and tense ascites. None had known lung disease or abnormal chest roentgenograms. At baseline, mean lung volumes, diffusing capacity, and arterial pO2 were all reduced from normal predicted values. Airflow, however, when related to lung volume, was normal. Post-LVP, lung volumes increased significantly; the mean expiratory reserve volume showed the greatest percent increase (105%) and correlated with the increases in the vital capacity, functional residual capacity, and total lung capacity. Airflow, the mean diffusing capacity, and arterial oxygenation were not significantly changed after LVP. We conclude that LVP significantly increases indices of lung volume but does not significantly alter parameters of airflow or gas exchange.