Abstract
Introduction: During pandemic influenza A H1N1 in 2009 a high prevalence of patients with ARDS was observed. There are few studies evaluating the pulmonary sequelae according to the severity of ARDS.
Objective: Evaluate pulmonary function and structure through static testing and high-resolution computer tomography (HRCT), with one year follow up of the ARDS survivors from pandemic influenza AH1N1
Methods: Prospective cohort study. 30 patients were included in two groups: severe ARDS vs mild to moderate according to Berlin definition and the use of invasive mechanical ventilation. Lung function tests were performed including spirometry, body plethysmography and DLCO. HRCT scans were also obtained, graded according to the Kazerooni scale. A comparison of the values obtained at 6 and 12 months follow up was performed.
Results: Median age 45 years (IQR 37-56) and 50% with severe ARDS was observed.
Regarding the respiratory function no results were observed below the lower limit of normal, even in the group with severe ARDS. Nevertheless a significant improvement between 6 and 12 months of follow-on TLC and DLCO were observed. (TLC 98.9% CI 90.8-106.3% vs 102% CI 94.0-109.5%, p<0.001; DLCO 105% CI 84.8-117.3% vs 113% CI 93.8-121%, p<0.001). HRCT imaging showed pattern of small airway disease and inflammation according to the Kazerooni scale at year follow-up (2.1 vs 1.0, p<0.001), but no significant difference was found between ARDS severity groups.
Conclusions: Ad integrum recovery of lung function in survivors of this pandemic virus regardless of the ARDS severity is expected. The first year of hospital discharge may be the window to optimize strategies in this patients.
- Copyright ©ERS 2015
