Point of Care Portable Spirometry in the Diagnosis and Treatment of Inpatients with Chronic Obstructive Pulmonary Disease.

INTRODUCTION: Spirometry is required to accurately diagnose chronic obstructive pulmonary disease (COPD). Following an acute exacerbation, it is recommended that spirometry be performed after a delay of 4-6 weeks to allow stability and a measure of 'baseline' lung function. However, poor attendance at these appointments can occur, leading to an inability to confirm the diagnosis of COPD or assess the severity of airflow obstruction. Portable spirometry (PS) is a proven surrogate device that may provide a convenient method to address these issues. The purpose of this study was to compare PS values, obtained prior to hospital discharge to laboratory-based spirometry (LS) results undertaken 4 weeks later.
METHODS: Thirty-three eligible inpatients with a clinically determined exacerbation of COPD were recruited. Patients underwent PS prior to discharge and LS 4 weeks later.
RESULTS: Reliability of PS values at discharge compared with outpatient LS 4 weeks later was excellent (intraclass correlation coefficient > 0.9). The PS confirmed a new diagnosis of COPD at the bedside in 29% of patients and excluded COPD in 6% at both time points. Patients were found to have a similar severity of airflow obstruction on both PS and LS, with clinical stability maintained between visits. The PS and LS may be used interchangeably for earlier diagnosis of COPD. PS at the point of discharge from hospital offers a unique opportunity to diagnose and facilitate COPD management from hospital to primary care.