Abstract
Background: There is currently no recognized discharge criteria for patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). In clinical work, pulmonologists determine whether a patient can be discharged considering the patient self-reported health status and some measurements which are related to the health status of AECOPD patients. Various measurements have been used to evaluate health status in patients with AECOPD, including lung function, fractional exhaled nitric oxide (FENO), blood gas analysis, COPD Assessment Test (CAT) and modified Medical Research Council test (mMRC). However, which one is most closely related to the patient self-reported health status remains unknown. Methods: Patients with AECOPD were assessed at two visits: on admission and on day 7. The above measurements were tested at each visit. At the second visit, the patients were asked to report the health status according to a five-point Likert scale ranging from 1 to 5, representing ‘much better’, ‘slightly better’, ‘no change’, ‘slightly worse’ and ‘much worse’. Based on patients self-reported outcome, we defined the responders as those patients who reported “much better,” or “slightly better”, non-responders were those who reported ‘no change,’ ‘slightly worse’ or ‘much worse’. Results: 55 patients were recruited into analysis. FENO and CAT could change sensitively based on different health status, except failing to differentiate the patients between those who reported ‘slightly better’ and ‘no changes’. The changes in predicted percentage of forced expiratory volume in 1 s (FEV1%) didn’t change significantly between ‘no change’ group and ‘slightly better or much better’ group, it could only identify the ‘slightly worse’ patients. Although mMRC and blood gas analysis (PaO2, PaCO2) changed significantly after treatment, they didn’t reflect sensitively the evolution of health status. Among these measurements, the changes in CAT was best correlated with the evolution of health status (Rho=0.81), followed by FENO and FEV1%, the rho was 0.59 and -0.42, respectively. Conclusion: It’s reasonable to monitor CAT and FENO during exacerbation stage, the use of lung function and mMRC to evaluate the evolution of patients’ reported health status of patients with AECOPD is limited. Registry number: ChiCTR-ROC-16009087 (http://www.chictr.org.cn/).
Relating oxygen partial pressure, saturation and content: the haemoglobin–oxygen dissociation curve
