Stoohs R, Guilleminault C
Stanford University Sleep Research Center, Palo Alto, California.
Chest. 1992 May;101(5):1221-7. doi: 10.1378/chest.101.5.1221.
A validation study was performed on the MESAM 4, a digital recording device developed to monitor oxygen saturation, heart rate (HR), snoring, and body position in order to screen subjects for obstructive sleep apnea syndrome (OSAS). MESAM 4 recordings were scored with the computer-based automatic scoring system provided with the equipment. Nocturnal polysomnography (PSG) and MESAM 4 recordings were run simultaneously on 56 subjects presenting with any type of sleep complaint, including those secondary to OSAS. Patients were assigned to one room by hospital administration and were monitored consecutively. The polygraphic equipment and MESAM 4 equipment were placed on the subjects by separate teams. Records of PSG and MESAM 4 were analyzed in double-blind fashion. With the MESAM 4 computerized analysis, three indices based on SaO2 (ODI), on heart rate (HVI), and on snoring (ISI) were obtained, and the number of abnormal respiratory events occurring during the time selected for analysis (TAT) were determined. Polysomnographic records were scored by 30-s epochs following the American Sleep Disorders Association standards for sleep states and stages and for sleep-related events, including sleep apneas, hypopneas, and periodic leg movements. Following independent scoring, 26 subjects were identified with OSAS by PSG, while MESAM 4 identified 25 subjects with OSAS using oxygen algorithm; all had a respiratory disturbance index greater than or equal to 10 with PSG. Results of each polysomnogram and each MESAM 4 analysis were compared. With the polysomnogram used as a standard, the degree of error for each variable with the MESAM 4 was calculated. Specificity and sensitivity of the most accurate index of the MESAM 4, the ODI, were 97 percent and 92 percent, respectively. The other two indices, HVI and ISI, were less accurate: specificity and sensitivity were 32 percent and 58 percent for HVI and 27 percent and 96 percent for ISI. Nevertheless, a combination of all three indices (ODI, HVI, ISI) would have prevented the two false-positive cases we observed. The results of this validation study show that MESAM 4 can be helpful to general practitioners, clinicians, and epidemiologists as a low-cost screening device for subjects with OSAS and habitual snoring.
对MESAM 4进行了一项验证研究，MESAM 4是一种数字记录设备，旨在监测血氧饱和度、心率（HR）、打鼾和身体姿势，以便对阻塞性睡眠呼吸暂停综合征（OSAS）患者进行筛查。MESAM 4的记录通过该设备配备的基于计算机的自动评分系统进行评分。对56名有任何类型睡眠问题（包括继发于OSAS的问题）的受试者同时进行夜间多导睡眠图（PSG）和MESAM 4记录。医院管理部门将患者分配到一个房间并进行连续监测。多导睡眠图设备和MESAM 4设备由不同的团队放置在受试者身上。PSG和MESAM 4的记录采用双盲方式进行分析。通过MESAM 4计算机分析，获得了基于血氧饱和度（ODI）、心率（HVI）和打鼾（ISI）的三个指标，并确定了在选定分析时间（TAT）内发生的异常呼吸事件数量。多导睡眠图记录按照美国睡眠障碍协会关于睡眠状态和阶段以及与睡眠相关事件（包括睡眠呼吸暂停、呼吸不足和周期性腿部运动）的标准，以30秒为一个时段进行评分。在独立评分后，PSG确定26名受试者患有OSAS，而MESAM 4使用氧算法确定25名受试者患有OSAS；所有受试者的PSG呼吸紊乱指数均大于或等于10。比较了每个多导睡眠图和每个MESAM 4分析的结果。以多导睡眠图为标准，计算了MESAM 4每个变量的误差程度。MESAM 4最准确指标ODI的特异性和敏感性分别为97%和92%。另外两个指标HVI和ISI的准确性较低：HVI的特异性和敏感性分别为32%和58%，ISI的特异性和敏感性分别为27%和96%。然而，将所有三个指标（ODI、HVI、ISI）结合起来本可以避免我们观察到的两例假阳性病例。这项验证研究的结果表明，MESAM 4作为一种低成本的筛查设备，对全科医生、临床医生和流行病学家筛查OSAS患者和习惯性打鼾者可能会有所帮助。
