RESUMO
Although polysomnography (PSG) is the golden standard for the diagnosis of sleep apnea syndrome (SAS), access to this procedure is limited because it requires special institution and trained technicians. Therefore, many portable recording devices have been developed for detection of SAS including home monitoring. The present study evaluated the usefulness of four portable devices in detecting apneic events. The four devices are, (1) FM-500 thermister sensor type III device, (2) LS-300 pressure sensor type III device, (3) Morpheus pressure sensor type III device, and (4) SD-101, a sheet-type type IV device that detects chest wall movement. This study included 1,114 patients who underwent a daytime rest session during a routine clinic visit. The subjects were asked to remain quiet and in a supine position in a dark room. We compared the respiratory disturbance index (RDI) and number of oxygen desaturation events (OD) measured by the four portable devices in each patient. The RDI and number of OD measured by the device using the thermister sensor were significantly lower than those measured by the three other devices. These findings suggest that when using a portable recording device to screen for SAS, the characteristics of the device should be taken into account.