慢性阻塞性肺疾病患者睡眠低氧的临床研究

目的 探讨慢性阻塞性肺疾病(COPD)患者睡眠低氧对睡眠相关指标的影响及其与日间指标的关系.方法 选择中度至极重度COPD患者204例,年龄40～75岁,平均(70.41±7.84)岁.按多导睡眠图(PSG)结果将研究对象分为低氧组和非低氧组,均行血气分析、肺功能和PSG监测.结果 睡眠低氧者95例,低氧率为46.57%.与非低氧组比较,睡眠低氧组日间动脉血氧饱和度(SaO2,0.90±0.04比0.94±0.01)和夜间平均动脉血氧饱和度(MSaO2,0.83±0.08比0.93±0.02)均明显降低(均P<0.01).低氧组和非低氧组间部分睡眠指标如醒觉时间(min:97.86±41.74、76.13±55.15)、醒觉次数(次:31.50±15.69、23.23±19.81)、平均心率(次/min:80.80±12.80、66.21±6.53)以及睡眠结构[(S1+S2)%:(74.36±16.52)%、(67.55±12.62)%,(S3+S4)%:(12.99±12.18)%、(19.35±12.71)%]比较差异均有统计学意义(均P<0.01).动脉血二氧化碳分压(PaCO2)、动脉血氧分压(PaO2)、1秒用力呼气容积(FEV1)占预计值百分比、用力肺活量(FVC)占预计值百分比、FEV1/FVC占预计值百分比分别与睡眠低氧指标如睡眠中SaO2<0.90的时间占总睡眠时间的百分比(T90)、MSaO2、最低动脉血氧饱和度(miniSaO2)存在相关关系,其中PaCO2与之的相关性最强(r1=0.767,r2=-0.758,r3=-0.689,均P<0.01).结论 中度至极重度COPD患者睡眠低氧普遍存在.睡眠低氧组与非低氧组在日间SaO2、夜间SaO2、睡眠监测指标方面存在差异.日间指标与睡眠低氧存在相关,部分可作为预测睡眠低氧的指标.

Study on hypoxemia during sleep in patients with chronic obstructive pulmonary disease

Objective To investigate the influence of hypoxemia during sleep on elements of polysomnography (PSG) in patients with chronic obstructive pulmonary disease (COPD) and the correlation of sleep hypoxemia and arterial blood gases, pulmonary function in daytime. Methods Two hundred and four moderate to very severe stable COPD patients with an age range of 40-75 years [mean age was (70.41±7.84) years] were admitted. All patients underwent overnight PSG, and percentage of the time with oxygen saturation below 0.90 and total sleep time (T90)≥5% was taken as nocturnal oxygen desaturation (NOD), and if not, they were non-NOD. Arterial blood gases, lung function and PSG examinations were performed in all patients. Results Ninety-five patients (46.57%) had NOD were enrolled. Compared with patients of non-NOD, both daytime oxygen saturation (SaO2, 0.90±0.04 vs. 0.94±0.01) and nocturnal mean SaO2 (MSaO2, 0.83±0.08 vs. 0.93±0.02) in NOD were lower significantly (both P<0.01). Sleep-related elements such as awake period (minutes: 97.86±41.74 vs. 76.13±55.15), awake frequency (times: 31.50±15.69 vs. 23.23±19.81), mean heart rate (beat per min: 80.80±12.80 vs. 66.21±6.53), sleep components [(S1+S2)%: (74.36±16.52)% vs. (67.55±12.62)%, (S3+S4)%: (12.99±12.18)% vs. (19.35±12.71)%] in NOD were significantly different from non-NOD (all P<0.01). The levels of arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of oxygen (PaO2), percentage of forced expiratory volume in one second (FEV1) and anticipate value, percentage of forced vital capacity (FVC) and anticipate value, percentage of FEV1/FVC and anticipate value in daytime were respectively correlated with the T90, MSaO2 and minimum SaO2 (miniSaO2) in sleep. Among these measurements, PaCO2 was best correlated with sleep hypoxemia (r1=0.767, r2=-0.758, r3=-0.689, all P<0.01). Conclusion Sleep hypoxemia existed generally in patients with moderate to very severe stable COPD. There was significant difference in nocturnal SaO2, daytime SaO2 and sleep-related elements between NOD and non-NOD. The measurements in daytime are correlated with sleep hypoxemia, and some of them may predict sleep hypoxemia.