高原地区慢性阻塞性肺疾病夜间睡眠吸氧时减氧饱和的研究

摘要

目的：探讨高原COPD患者夜间睡眠吸氧时氧饱和度的变化。方法：对40例高原COPD患者白天肺功能、呼吸空气和吸氧时血气、夜间呼吸空气和吸氧时的SaO2进行比较分析。结果：夜间睡眠呼吸空气时平均SaO2(MSaO2)显著降低，SaO2＜85％时间占总监测时间百分比(T 85)为86.3％；吸氧时MSaO2为87.4％。以T 85＞30％将本组分为无减氧饱和(A组，占55％)及减氧饱和(B组，占45％)组，睡眠呼吸空气或吸氧时B组MSaO2和最低SaO2(MmSaO2)显著低于、T 85显著高于A组(P均＜0.01)。B组FEV1显著低于A组(P＜0.01)；白天呼吸空气或吸氧时B组PaO2显著低于、PaCO2显著高于A组(P＜0.01或＜0.05)。睡眠呼吸空气或吸氧时MSaO2、T 85与FEV1、SaO2呈正相关，与PaCO2呈负相关(P均＜0.01)。结论：高原COPD患者睡眠呼吸空气时有明显减氧饱和，吸氧时约半数减氧饱和。%Objective:To study the occurrence of nocturnal desaturations while breathing oxygen in patients with chronic obstructive pulmonary disease (COPD) at high altitudes. Methods:Daytime pulmonary function, arterial blood gases and nocturnal oxyhemoglobin saturation (SaO2) while breathing air and oxygen were measured in 40 patients with COPD at high altitudes.Results:①Mean SaO2 (MSaO2) while nocturnal sleep breathing air in patients with COPD markedly decreased. The percentage of SaO2 ＜85％ (T85) time in total recording time was 86.3％. MSaO2 while nocturnal sleep breathing oxygen was 87.5％.②Using a cutoff point of T 85＞30％, the patients were divided into nondesaturators (group A, 22 cases, 55％)and desaturators (group B, 18 cases, 45％). MSaO2 and minimum SaO2 (MmSaO2) in group B were markedly lower, and T 85 were markedly higher than those in group A while nocturnal sleep breathing air and oxygen (all P＜0.01).③FEV1 and PaO2 in group B were significantly lower and PaCO2 were significantly higher than those in group A while daytime breathing air and oxygen (all P＜0.01 or P＜0.05).④Despite of breathing air and oxygen,the nocturnal MSaO2 and T85 were positively correlated with daytime FEV1 and SaO2 ,and were negatively correlated with daytime PaCO2 (all P＜0.01).Conclusion:Desaturation while nocturnal breathing air is remarkable in COPD patients at high altitudes.About half of COPD patients occur desaturations during sleep despite of breathing oxygen and need to increase oxygen flow during sleep.