Pulmonary function testing
Pulmonary function tests were performed in a negative-pressure room by a technician wearing protective equipment to prevent transmission. The patients’ age, height, and weight were measured and recorded. Before testing, patients were instructed to abstain from smoking (24 hours), alcohol (4 hours), strenuous exercise (30 minutes), and heavy meals (2 hours). Tests were performed with the patients lightly dressed. BTPS correction was performed according to room air and barometric pressure. The technician explained the desired maneuvers to the patients and they performed 3 acceptable spirograms. Tests that met the reproducibility and acceptability criteria were included in our analysis. All spirometry was performed by the same technician using a Plusmed MIR Spirolab III device.