Validation of a seven-channel device for ambulatory screening of obstructive sleep apnea. Part 1: Handling of the device for the physician and the patient

Purpose: For some time,the ambulatory diagnosis of sleep-related breathing disorders has included the use of seven-channel recording units. One such u nit is the POLY-MESAM (MAP, Martinsried, FRG). The first part of the presen t study prospectively investigated the handling of the system for physician s and patients, its technical reliability, reliability of the software used and the results in comparison to handscoring. Methods:ln all, 104 patients (95 males, 9 females) were studied for differe nt severities of obstructive sleep-related breathing disorders. The first 5 1 patients were connected to the POLY-MESAM in the evening within the clini c. The patients then slept at home and returned the next day. Another 53 pa tients received only a short briefing in the clinic and connected themselve s at home to the POLY-MESAM System. Each patient's status was monitored by means of a visual analogue scale. Automatic evaluation of the data was comp ared with the results of manual scoring. Results: From the data recorded only 6% of the results were not usable. Pat ients acceptances of the system were very high (94.3%). On average each pat ient required 21 minutes for attaching and detatching the device. Scoring a nd instructing the patients required an average of 23 min. Regarding the ap nea-hypopnea index (AHI), the correlation between automatic (AHI=11.1) and manual (AHI=11.3) evaluations was high. Analysis of snoring turned out to b e insufficient. Conclusions:The POLY-MESAM proved to be reliable and user-friendly. Our fin dings show that the system can be recommended for outpatient screening of s leep-related breathing disorders, with patients able to manage the system w ithout help. Validation by using simultaneous polysomnography is the subjec t of part two of the study.