Recovery of pulmonary functions, exercise capacity, and quality of life after pulmonary rehabilitation in survivors of ARDS due to severe influenza A (H1N1) pneumonitis

BackgroundAcute respiratory distress syndrome (ARDS) due to severe influenza A H1N1 pneumonitis would result in impaired pulmonary functions and health-related quality of life (HRQoL) after hospital discharge. ObjectivesThe recovery of pulmonary functions, exercise capacity, and HRQoL in the survivors of ARDS due to 2009 pandemic influenza A H1N1 pneumonitis (H1N1-ARDS) was evaluated in a tertiary teaching hospital in northern Taiwan between May 2010 and June 2011. Patients and MethodsData of spirometry, total lung capacity (TLC), diffusing capacity of carbon monoxide (DLCO), and 6-minute walk distance (6MWD) in the patients survived from H1N1-ARDS were collected 1, 3, and 6months post-hospital discharge. HRQoL was evaluated with St. George respiratory questionnaire (SGRQ). ResultsNine survivors of H1N1-ARDS in the study period were included. All these patients received 2months' pulmonary rehabilitation program. Pulmonary functions and exercise capacity included TLC, forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), DLCO, and 6MWD improved from 1 to 3months post-hospital discharge. Only TLC had further significant improvement from 3 to 6months. HRQoL represented as the total score of SGRQ had no significant improvement in the first 3months but improved significantly from 3 to 6months post-discharge. ConclusionThe impaired pulmonary functions and exercise capacity in the survivors of H1N1-ARDS improved soon at 3months after hospital discharge. Their quality of life had keeping improved at 6months even though there was no further improvement of their pulmonary functions and exercise capacity.