Analysis of nose respiratory movements during swallowing

Abstract

We examined nose respiratory movements during swallowing and evaluated the usefulness of measuring these movements as a method of clinical examination in comparison with other conventional methods. Using a differential pressure-type air flowmeter, we determined nose respiratory movements in normal subjects. In addition, we measured EMG activity of the geniohyoid muscle, as well as laryngeal, thorax and abdomen vallum motions. We also examined the reliability of current differential pressure-type air flowmeters used for measuring nose respiratory movements. Our results showed that the dispersion was smaller for the time used for arrest of nose respiration than was that of other parameters (p<0.01). With an optimal volume for swallowing (20 mL), we found that nose respiration was arrested to retard the onset of electromyogram activity and the onset of laryngeal motion. It was initiated later than the offset of EMG activity and earlier than the offset of laryngeal motion (p<0.01). However, the results were different when swallowing volume exceeded 20 mL. These findings indicate that the current method of determining nose respiratory movements is more accurate and easier to use than other measuring devices, and is useful for clinical examinations of swallowing.