title: Effect of indomethacin on arterial oxygenation in critically ill patients with severe bacterial pneumonia.
abstract: The effect of indomethacin (1 mg/kg) on gas exchange was studied in ten patients with hypoxaemic respiratory failure precipitated by bacterial pneumonia. Mean arterial oxygen tension (PaO2) improved significantly (79 +/- 16 mm Hg to 98 +/- 20 mm Hg) but the response varied between patients: five showed substantial responses (27-42 mm Hg), three lesser responses (7-9 mm Hg), and two no response. Similar changes were found in the alveolar-arterial oxygen gradient and the ratio of PaO2 to fractional inspired oxygen concentration. In two responders studied further, PaO2 had fallen to baseline values 4-6 h later and a repeat indomethacin challenge again increased PaO2 by greater than 25 mm Hg with concomitant changes in pulmonary shunt. There were no significant changes in the other gas-exchange or haemodynamic variables measured and there was no clear reason for the variability in response to indomethacin. These results suggest a role for products of the cyclo-oxygenase pathway of arachidonic acid metabolism in the pathogenesis of hypoxaemia in patients with severe bacterial pneumonia.
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000150:complications / Q000188:drug therapy*; D003422:Critical Care; D006801:Humans; D000860:Hypoxia / Q000188:drug therapy* / Q000209:etiology; D007213:Indomethacin / Q000627:therapeutic use*; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D011014:Pneumonia / Q000150:complications / Q000188:drug therapy*; D011659:Pulmonary Gas Exchange / Q000187:drug effects
chemical_list: D010100:Oxygen; D007213:Indomethacin