Heijdra Y F, Dekhuijzen P N, van Herwaarden C L, Folgering H T
Department of Pulmonary Diseases, University of Nijmegen, Medical Centre Dekkerswald, Groesbeek, The Netherlands.
Thorax. 1995 Jun;50(6):610-2. doi: 10.1136/thx.50.6.610.
Nocturnal desaturations, mainly caused by hypoventilation, occur frequently in patients with chronic obstructive pulmonary disease (COPD). Daytime arterial oxygen and carbon dioxide tensions (PaO2 and PaCO2) appear to predict which patients will desaturate at night. It is unknown if respiratory muscle strength, which may be decreased in these patients, plays an additional part.
Polysomnography, maximal respiratory pressures, lung function, and arterial blood gas tensions were measured in 34 patients with COPD (mean (SD) forced expiratory volume in one second (FEV1) 41.7 (19.9)% pred).
Significant correlations were found between the mean nocturnal arterial oxygen saturation and maximal inspiratory mouth pressure (r = 0.65), maximal inspiratory transdiaphragmatic pressure (r = 0.53), FEV1 (r = 0.61), transfer coefficient (KCO) (r = 0.38), arterial oxygen saturation (SaO2) (r = 0.75), and PaCO2 (r = -0.44). Multiple regression analysis showed that 75% of the variance in nocturnal SaO2 (70%) and FEV1 (5%).
Inspiratory muscle strength and nocturnal saturation data are correlated, but daytime SaO2 and FEV1 remain the most important predictors of nocturnal saturation.
夜间低氧饱和度主要由通气不足引起,在慢性阻塞性肺疾病(COPD)患者中频繁出现。日间动脉血氧和二氧化碳分压(PaO2和PaCO2)似乎可以预测哪些患者夜间会出现低氧饱和度。尚不清楚这些患者可能降低的呼吸肌力量是否起额外作用。
对34例COPD患者(一秒用力呼气容积(FEV1)平均(标准差)为预计值的41.7(19.9)%)进行多导睡眠图、最大呼吸压力、肺功能和动脉血气分压测量。
发现平均夜间动脉血氧饱和度与最大吸气压(r = 0.65)、最大吸气跨膈压(r = 0.53)、FEV1(r = 0.61)、转移系数(KCO)(r = 0.38)、动脉血氧饱和度(SaO2)(r = 0.75)和PaCO2(r = -0.44)之间存在显著相关性。多元回归分析显示,夜间SaO2变异的75%(70%)和FEV1变异的5%。
吸气肌力量与夜间饱和度数据相关,但日间SaO2和FEV1仍然是夜间饱和度最重要的预测指标。