UPPER AIRWAY MUCOSA TEMPERATURE IN OBSTRUCTIVE SLEEP APNOEA HYPOPNOEASYNDROME, NONAPNEIC SNORERS AND NONSNORERS/

Upper airway (UA) inflammation (oedema and hyperaemia) is frequently o bserved in snorers and patients with sleep apnoea/hypopnoea patients. The temperature of different UA regions measured in 11 male nonsnorers , 13 non-apnoeic snorers and 10 untreated sleep apnoea/hypopnoea syndr ome (SAHS) patients using infra-red video recording. Measurements were taken with the mouth open during tidal volume mouth breathing, and at the beginning and end of a 10 s end-inspiratory voluntary apnoea whic h followed either mouth or nasal breathing. Three measurements were ob tained from the uvula and from each side of the posterior pharyngeal w all and two from each side of the soft palate. The different UA region s were characterized by their inspiratory temperature, the expiratory rewarming and the changes in UA temperature during apnoea, The tempera ture of the uvula was significantly lower than that of the other UA re gions. For each anatomical region, there were no differences in inspir atory temperature between normals, snorers and SAHS, In normals, the e xpiratory rewarming was significantly higher in the uvula than in the velum and the posterior pharyngeal wall, whereas these regional differ ences mere not observed in snorers and SAHS, The velum and posterior p haryngeal rewarming was significantly less in normals than in snorers and SAHS. During apnoea, the UA rewarming was similar to that observed during expiration. In conclusion, tissue temperature varies between t he different upper airway regions and during tidal breathing and the i ntensity of the regional expiratory rewarming differs between normals, snorers and patients with sleep apnoea/hypopnoea syndrome.