Significance of a screening device (Apnomonitor 5) for sleep apnea syndrome.

Objectives: The objective was to evaluate the significance of a portable sleep-monitoring device (Apnomonitor 5, Chest Co., Tokyo, Japan) to diagnose sleep apnea syndrome (SAS).

Methods: The Apnomonitor 5 comprised an oronasal thermistor, a pulse oximeter, chest and abdominal belts to monitor the circumferences of the chest and abdomen, a microphone to monitor tracheal sound, a position detector, and an integrative unit. This screening device was commercially available and it had been used to diagnose SAS in our country. Twenty-two consecutive adults who attended Inazawa City Hospital who were suspected for SAS were prospectively enrolled and they undertook the standard polysomnography (PSG) and Apnomonitor 5 simultaneously. The designated polysomnographers analyzed the records of the PSG and Apnomonitor 5. These sleep and respiratory parameters of the devices were compared, the results of which were double-checked by the designated sleep specialist.

Results: The apnea-hypopnea index (AHI), apnea index, total number of apnea, and oxygen desaturation index obtained by the PSG and Apnomonitor 5 correlated significantly, whereas the averaged sleep time, total number of hypopnea, hypopnea index, and nadir oxygen saturation differed between the devices. The sensitivity of the Apnomonitor 5 versus PSG was 95% in the SAS patients with the AHI> or =15.

Conclusions: The Apnomonitor 5 can be a sensitive and useful screening device for SAS especially in patients with the AHI> or =15.