Peak flow nasal patency indices in patients operated for nasal obstruction.

In 26 patients undergoing operation for nasal obstruction, nasal and oral peak expiratory and inspiratory flow rates were measured preoperatively and 1 month postoperatively. Peak expiratory and inspiratory flow nasal patency indices were calculated from the ratio between the nasal and oral peak flow rates. Postoperatively, these indices were significantly increased for the total nose and for the preoperatively worse nasal cavity. No significant change was observed for the oral peak flow rates. A significant preoperative difference in nasal patency between the two nasal cavities was eliminated by surgery, as the postoperative peak flow of each nasal cavity reached 80% of the peak flow of the total nose on expiration and close to 50% on inspiration. A good correspondence between the subjective improvement of nasal patency and the increase in peak expiratory and inspiratory flow nasal patency indices was observed for the total nose. These findings show that peak flow nasal patency indices give valuable information pre- and post-operatively in patients undergoing nasal surgery and that the method is simple and easy to perform.