The Analysis Of Pulmonary Function And Sleep Morning Of Chronic Obstructive Pulmonary Disease With Sleep Apnea Syndrome

Objective:The present study compares the lung function,blood gas analysis,and sleep monitoring of COPD patients,SAS patients,and OS patients and discusses the characteristics of OS group in lung function,blood gas analysis,and sleep detection to improve the clinicians’ cognition,thereby improving clinicians’ awareness of OS diagnosis and achieving early treatment of OS patients,and improving the quality of life of patients.Methods: 169 patients admitted to the respiratory department from February 2018 to December 2019 were recruited to collect the general characteristics of the patients and the results of sleep monitoring,blood gas analysis.According to AHI and results of lung function all patients were divided into 3 groups:SAS（N=71）;OS（N =70）and COPD（N=28）.To evaluate the similarities and differences among the three groups and analyze the correlation of the PaCO₂.We divided the OS patients into hypercapnic（PaCO₂ 45 mm Hg）and normocapnic（PaCO₂ < 45 mm Hg）groups assess differences between the two groups Results1.General characteristics: No differences regarded age,smoking index,and BMI in COPD vs OS but both had higher age and smoking index than SAS both had a lower BMI than SAS.2.Lung function: No differences regarded FVCpred（%）and FEV1%pred in COPD vs OS but had differences regarding FVCpred（%）and FEV1%pred in COPD vs SAS and in OS vs SAS.FVCpred（%）and FEV1%pred were lower in COPD than in SAS.FVCpred（%）and FEV1%pred were higher in SAS than in OS.3.Arterial blood gas analysis: There was no difference regarding PaO₂ in the COPD,the SAS and the OS.There were differences regarding PaCO₂,HCO3-in COPD vs SAS and in OS vs SAS.PaCO₂ and HCO3-were higher in COPD than in SAS.PaCO₂ and HCO3-were lower in SAS than in OS.4.Sleep monitoring: No differences were found regarding HYP/AHI% in COPD vs OS but both had a higher HYP/AHI% than SAS.No differences regarding TS% in COPD vs SAS but had differences in COPD vs OS and in SAS vs OS.In the OS group T90% was higher than in the COPD group.TS90% was higher in OS than in SAS.5.The Correlation of PaO₂: The PaO₂ had a positive correlation with FVC%pred（r=0.036,p=0.005<0.05）,and a negative correlation with AHI and TS90%（r =-0.335,-0.411;p<0.05）in OS patients,but In patients with SAS,PaO₂ was negatively correlated with the smoking index,AHI and TS90%（r=-0.362,-0.344,-0.285;p<0.05）,but positively correlated with FVC%pred and FEV1%pred（r= 0.310,0.304;p<0.05）.6.The correlation of AHI: In the OS group,BMI was positively correlated with AHI（r= 0.376 p = 0.001）,smoking index,PaO₂ was negatively correlated with AHI（r values were-0.300,-0.335,p <0.05）;In SAS,BMI and AHI were positively correlated（r value 0.413,p = 0.000 <0.05）;FVC%pred,PaO₂ and AHI were negatively correlated（r values were-0.360,-0.344,p <0.05）.7.The correlation of PaCO₂: In the COPD group,FEV1%pred was negatively correlated with PaCO₂（r =-0.572,p = 0.001）.In the OS group,FEV1%pred,PaO₂ and PaCO₂ were negatively correlated（r values were-0.392,-0.383,p <0.05）,and TS90% were positively correlated with PaCO₂（r = 0.416,p = 0.000）;,TS90% is positively correlated with PaCO₂（r = 0.256,p = 0.032）8.In the OS group,FVC%pred,FEV1% pred,FEV1 / FVC%,TS90% of patients with PaCO₂≥45mm Hg and PaCO₂ <45mm Hg are different,and lung function indexes FVC% pred,FEV1% pred,FEV1 in patients with high PaCO₂ / FVC% is lower than patients with normal PaCO₂,and its sleep index TS90% is higher than patients with normal PaCO₂.Conclusion:1.BMI is a risk factor for COPD combined with OSA2.There is no difference in lung ventilation between COPD patients and OS patients.3.Patients with OS have a higher risk of respiratory failure than patients with SAS alone.4.The COPD patients and OS patients is mainly hypoventilation,and the SAS patients are mainly apnea during sleep.5.Overlap individuals spent more time in desaturation than the SAS group and COPD group.6 Patients with OS combined with high PaCO₂ have worse nighttime hypoxia than those with normal PaCO₂.7 Compared with OS patients with normal PaCO₂,OS patients with high PaCO₂ had worse lung ventilation function.