Using the Nationwide Inpatient Sample (NIS) database, we performed a retrospective cross-sectional study based on admissions of adult patients (aged ≥ 18 years) who underwent LVRS (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 32.22) from 2000 to 2010. The NIS database is an administrative dataset created by the Agency for Healthcare Research and Quality that contains data from all community hospitals in the United States. Using the discharge weights in the NIS, national estimates can be obtained.4 The primary outcome measure was all-cause in-hospital mortality. Factors associated with in-hospital mortality were examined by a multivariable logistic regression model. We used ICD-9-CM codes to identify comorbid conditions and rates of tracheostomy (ICD-9-CM procedure codes 31.1, 31.2, 31.21, 31.29).