Coffey M J, FitzGerald M X, McNicholas W T
Department of Respiratory Medicine, University College, Dublin, Ireland.
Chest. 1991 Sep;100(3):659-62. doi: 10.1378/chest.100.3.659.
Patients with cystic fibrosis (CF) desaturate during sleep and during exercise but by different mechanisms. To determine the need for supplemental oxygen, many centers measure resting and exercise arterial oxygen saturation (SaO2). We examined the associations among resting, sleep, and exercise SaO2 to ascertain the validity of this approach. We studied 21 adult and adolescent CF patients, eight of whom were hypoxemic (SaO2 less than 95 percent; group A) and 13 of whom were nonhypoxemic (SaO2 greater than or equal to 95 percent; group B) by overnight oximetry and treadmill exercise testing. The whole group desaturated more during sleep than during exercise, the change in SaO2 being 10.59 +/- 8.35 vs 6.25 +/- 4.44 (p less than 0.002). Group B desaturated significantly more during sleep than during exercise, with a reduction in SaO2 of 7.9 +/- 3.3 vs 3.3 +/- 1.49 (p less than 0.05). Group A desaturated more during exercise than group B, with a reduction of 11 +/- 3.2 vs 3.3 +/- 1.5 (p less than 0.001). Despite a strong correlation between awake SaO2 and mean sleep SaO2 (r = 0.68; p less than 0.001), minimum sleep SaO2 (r = 0.55; p less than 0.01), and minimum exercise SaO2 (r = 0.92; p less than 0.001), there was no correlation between awake SaO2 and sleep-related desaturation or between exercise- and sleep-related desaturation. In conclusion, clinically significant oxygen desaturation during sleep may be missed unless specifically checked in CF patients, and awake and exercise SaO2 may not give an indication of the degree of sleep-related desaturation.
囊性纤维化（CF）患者在睡眠和运动期间会出现血氧饱和度下降，但机制不同。为了确定是否需要补充氧气，许多中心会测量静息和运动时的动脉血氧饱和度（SaO2）。我们研究了静息、睡眠和运动时的SaO2之间的关联，以确定这种方法的有效性。我们对21名成年和青少年CF患者进行了研究，通过夜间血氧饱和度监测和跑步机运动测试，其中8名患者存在低氧血症（SaO2低于95%；A组），13名患者无低氧血症（SaO2大于或等于95%；B组）。整个研究组在睡眠期间的血氧饱和度下降幅度大于运动期间，SaO2的变化分别为10.59±8.35和6.25±4.44（p<0.002）。B组在睡眠期间的血氧饱和度下降幅度明显大于运动期间，SaO2降低了7.9±3.3和3.3±1.49（p<0.05）。A组在运动期间的血氧饱和度下降幅度大于B组，分别为11±3.2和3.3±1.5（p<0.001）。尽管清醒时的SaO2与平均睡眠SaO2（r=0.68；p<0.001）、最低睡眠SaO2（r=0.55；p<0.01）和最低运动SaO2（r=0.92；p<0.001）之间存在很强的相关性，但清醒时的SaO2与睡眠相关的血氧饱和度下降之间或运动与睡眠相关的血氧饱和度下降之间均无相关性。总之，除非对CF患者进行专门检查，否则可能会漏诊睡眠期间临床上显著的氧饱和度下降，而且清醒和运动时的SaO2可能无法表明与睡眠相关的血氧饱和度下降程度。
