Conclusions
Tonic stimulation of the pharyngeal mucosa with cold dry air causes pain and an increase of inflammatory mediators which are reversible.
Results
Optimum conditions for tonic pharyngeal stimulation were cold dry air at 12 °C, relative humidity 20 %, at a flow rate of 12 L/min for 15 min. Analysis of pharyngeal lavage fluid collected 5 min after stimulation showed significant increases in prostaglandin E&sub2; (P = 0.018), thromboxane B&sub2; (P < 0.001), and substance P (P < 0.001), but no increase in peptidoleukotriene. When the stimulus was removed, the level of inflammatory markers in pharyngeal lavage fluid returned to baseline by 30 min post-stimulation. These objective measures mirrored subjective pain ratings. Conclusions: Tonic stimulation of the pharyngeal mucosa with cold dry air causes pain and an increase of inflammatory mediators which are reversible.