Changes in airway resistance following droperidol, hydroxyzine, and diazepam in normal volunteers.

The effects of droperidol, hydroxyzine, and diazepam on airway resistance (AR), functional residual capacity (FRC), and thoracic gas volume (TGV) were compared, using a CPI model-2000 body plethysmograph. Significant decreases in AR were seen following droperidol and hydroxyzine at all time intervals. A significant increase in AR also was noted 90 minutes after diazepam injection. FRC significantly decreased at 60, 90, 120, and 150 minutes following droperidol, and at 90 minutes following hydroxyzine, while no change was seen following diazepam. No significant changes in TGV were seen following administration of any of the drugs.