Management of arterial hypoxemia induced by fiberoptic bronchoscopy.

Twenty patients undergoing fiberoptic bronchoscopy (FOB) (bronchofiberscopy) were studied with serial arterial blood gas analyses. Ten patients were managed using a 40 percent Venturi mask with a 2-cm opening cut out for the FOB; there were ten other patients, with this opening modified by a thin rubber diaphragm with a slit for insertion of the FOB. Both masks decreased the extent of hypoxemia after bronchoscopy, but the mask with the diaphragm provided significantly higher PaO2 values. A significantly higher mean FIO2 was found at the carina in the group using the diaphragm-modified mask. This study suggests that declines in PaO2 after bronchoscopy can be avoided in most patients undergoing diagnostic FOB by using a diaphragm-modified 40 percent Venturi mask during and after the procedure. However, patients with a PaO2 below 60 mm Hg before bronchoscopy may require other measure to avoid potentially hazardous degrees of hypoxemia after bronchoscopy.