- Relationship between FEV1 and PaO2, PaCO2 in Patients with Chronic Bronchitis

It is necessary to determine the value of PaO2 and PaCO2 in COPD patients for diagnosis the severity of chronic bronchitis diseases and their separation from other diseases.For the diagnosis of COPD diseases and their separation from other diseases and for having a criterion for treatment with oxygen, we need to know the amount of Pao2 and PaCO2 in patients; ABG is an invasive and difficult procedure. This cross sectional study was carried out on 118 consecutive patients with chronic bronchitis referring to Afshar hospital in Yazd in order to determine the correlation between spirometry FEV1 and ABG parameters. The study population included 82 (69.5%) males and 36(30.5%) females with the mean age of 71.6±9 years. The mean FEV1 (% pred.) was 42.88±15.12, mean PaO2 was 55.31±13.51 mmHg and mean PaCO2 was 51.64±10.56 mmHg. FEV1 was positively correlated with PaO2 (r=0.418, p<0.0001) and inversely correlated with PaCO2 (r= -0.533, p<0.0001). One could establish a reliable equation indicating the correlation between FEV1 and PaO2 as well as PaCO2 in patient with chronic bronchitis.