Introduction:The in luenza A (H1N1) was responsible for the 2009 pandemic, especially with severe pulmonary complications. Objective: To describe characteristics of patients in a university hospital in Curitiba -PR with laboratory diagnosis of in luenza A (H1N1) and its post hospital discharge in the 2009 lung function pandemic Methodology: A retrospective observational study. It was used as a data source the institution Epidemiology Service (SEPIH) and spirometry tests of patients who were admitted in 2009, 18 years without lung disease associated and non-pregnant. Descriptive statistics were used and applied Fisher's exact test for relationship between comorbidity and spirometry tests. Results: There were 84 con irmed cases, of these 11 were eligible for the study with a mean age of 44.27 years (± 9.63) and 63.63% males. 54.54% of the 11 patients had comorbidities associated with systemic arterial hypertension (54.54%), diabetes (18.18%) and late postoperative period of kidney transplantation (18.18%) were the most frequent. Most patients (81.81%) had BMI ≥ 25kg / m². The Spirometry test was performed approximately 40.09 (± 15.27) days after discharge, of these, 5 had restrictive pattern and all had abnormal chest radiograph results. There was no statistically signi icant difference between the results of Spirometry and comorbidities (p=0.24). Conclusions: The group evaluated in this research did not show a direct relationship between Spirometry and comorbidities, but changes in Spirometry in some patients after hospital discharge stood out, suggesting changes in lung function due to in luenza A (H1N1). Keywords