A clinical evaluation of the Cottle rhinomanometry "flow" nozzle.

A clinical study was undertaken to establish what changes in values were caused by the nozzle used in the Cottle flow-pressure technique of rhinomanometry. Cottle rhino-sphygmo-manometry was performed over seven hundred times, half with the nozzle and half without and the results analyzed using pattern, rate, amplitude, work co-efficient and four breath factor as outlined by Cottle. In many instances marked changes did occur but were unpredictable by examination prior to testing. It is suggested that Cottle rhino-sphygmo-manometry be carried out routinely with and without this nozzle in order to better evaluate results of flow-pressure relationship in which this nozzle is used.