Study On The Related Factors Of Nocturnal Oxygen Desaturation In Patients With Chronic Obstructive Pulmonary Disease

Objective:1.To investigate the presence of nocturnal hypoxemia in patients with COPD;2.What are the factors associated with nocturnal hypoxemia in COPD patients during the daytime?Methods:Selecting from June 2017 to December 2017,51 patients with COPD who were stable in the Department of Respiratory Medicine at the Second Affiliated Hospital of Nanchang University or in the ward for nocturnal blood oxygen monitoring,and improved questionnaires to measure height,weight,and neck circumference,abdominal circumference,perfect blood gas analysis,lung function,6-minute walk test during daytime awake state.According to nocturnal blood oxygen monitoring results,nocturnal oxygen saturation monitoring showed SpO2?88%?adults?and time was?5 minutes;and no sleep-related hypoventilation was sleep hypoxia?NOD?group,otherwise non-night noxious?non-NOD?group.Collect and integrate experimental data,and use SPSS21.0 statistical software to analyze,the main statistical methods include?²test,Pearson correlation analysis,descriptive analysis,one-way analysis of variance,multi-factor Logistic regression analysis.Results:In this study,51 patients with COPD were classified according to lung function,1?2%?mild,12?24%?moderate,20?39%?severe,and 18?35%?extremely severe.There were 23 cases?45%?of nighttime hypoxia.After the?² test,with the decline of lung function,the incidence of sleep-related hypoxemia gradually increased,and the difference was statistically significant.There was no significant difference in age,BMI,neck circumference and waist circumference between sleep NOD and Non-NOD groups.In daytime lung function index,the FEV₁ value,FEV₁/FVC,FEV₁/prediction of NOD group were lower than that of Non-NOD group,and the difference was statistically significant?P<0.05?.NOD in the blood during the day,arterial partial pressure of oxygen and blood oxygen saturation was lower than the Non-NOD group,and the partial pressure of carbon dioxide was higher than that of the Non-NOD group.The 6-min walk test in the NOD group was lower than in the Non-NOD group,and the dyspnea?mMRC score?was higher than in the non-sleep hypoxia group.NOD night LSaO₂,MSaO₂ were lower than the Non-NOD group,and ODI,T88 and T88%were higher than the Non-NOD group,and there was no significant difference in AHI values.Mean oxygen saturation,minimum oxygen saturation,T88,oxygen reduction index,T88%and daytime FEV₁,FEV₁/FVC,FVC,FEV₁/predicted,arterial partial pressure of oxygen,arterial oxygen saturation during sleep,There was a statistically significant correlation between the partial pressure of carbon dioxide,the mMRC score,and the 6-minute walk test.After a stepwise approach,we obtained the prediction formulas for LSaO₂,MSaO₂,T88?%?and T88.T88=0.99-0.356MWT+3.816PaCO₂?r=0.686?,MSaO2?%?=96.924-0.145PaCO₂+0.057FEV₁/FVC?r=0.683?,LSaO₂?%?=173.217-0.686PaCO₂-0.595SaO₂-0.129FEV₁/expec ted?r=0.639?,T88?%?=0.925PaCO₂-0.069*6MWT-6.776?r=0.683?,Logistic regression showed that 6MWT,PaCO₂,FEV₁/FVC,FEV₁/predicted statistically significant sleep Related hypoxia factors.And draw the curve of T88 fit:y=0.0508X²-1.1558X.Conclusion:1.45%of patients with stable COPD had nocturnal hypoxemia.2.The incidence of nocturnal hypoxia is negatively correlated with FEV1/prediction.3.The FEV₁/FVC,FEV₁/predicted,PaO₂,SaO₂,and 6MWT in the NOD group were lower than that in the Non-NOD group.The mMRC score in the NOD group and PaCO₂ during the day were higher than that in the Non-NOD group.4.6MWT,PaCO₂,FEV₁/FVC,FEV₁/predicted T88,T88?%?,MSaO₂,and La SO₂.6MWT and PaCO₂ were the key risk factors for sleep-related hypoxemia.