Epidemiological trends in invasive mechanical ventilation in the United States: A population-based study

Abstract

PurposeEpidemiological trends for invasive mechanical ventilation (IMV) have not been clearly defined. We sought to define trends for IMV in the United States and assess for disease-specific variation for 3 common causes of respiratory failure: pneumonia, heart failure (HF), and chronic obstructive pulmonary disease (COPD). MethodsWe calculated national estimates for utilization of nonsurgical IMV cases from the Nationwide Inpatient Sample from 1993 to 2009 and compared trends for COPD, HF, and pneumonia. ResultsWe identified 8309344 cases of IMV from 1993 to 2009. Utilization of IMV for nonsurgical indications increased from 178.9 per 100000 in 1993 to 310.9 per 100000 US adults in 2009. Pneumonia cases requiring IMV showed the largest increase (103.6%), whereas COPD cases remained relatively stable (2.5% increase) and HF cases decreased by 55.4%. Similar demographic and clinical changes were observed for pneumonia, COPD, and HF, with cases of IMV becoming younger, more ethnically diverse, and more frequently insured by Medicaid. Outcome trends for patients differed based on diagnosis. Adjusted hospital mortality decreased over time for cases of pneumonia (odds ratio [OR] per 5 years, 0.89; 95% confidence interval [CI], 0.88-0.90) and COPD (OR per 5 years, 0.97; 95% CI, 0.97-0.98) but increased for HF (OR per 5 years, 1.10; 95% CI, 1.09-1.12). ConclusionUtilization of IMV in the US increased from 1993 to 2009 with a decrease in overall mortality. However, trends in utilization and outcomes of IMV differed markedly based on diagnosis. Unlike favorable outcome trends in pneumonia and COPD, hospital mortality for HF has not improved. Further studies to investigate the outcome gap between HF and other causes of respiratory failure are needed.