Outcomes and Resource Use Associated with Acute Respiratory Failure in Safety Net Hospitals Across the United States.

BACKGROUND Despite the frequency and cost of hospitalizations for acute respiratory failure, there is a paucity of literature regarding the impact of hospital safety net burden on outcomes of these hospitalizations. RESEARCH QUESTION How does safety net burden impact outcomes of acute respiratory failure hospitalizations such as mortality, tracheostomy and resource utilization? STUDY DESIGN AND METHODS This was a retrospective cohort study using the National Inpatient Sample 2007-2017. All patients hospitalized with a primary diagnosis of acute respiratory failure were tabulated using the International Classification of Diseases 9thand 10thRevision codes and safety net burden was calculated using previously published methodology. High and low burden hospitals were generated from proportions of Medicaid and uninsured patients. Trends were analyzed using a non-parametric rank-based test while multivariable logistic and linear regression models were utilized to establish associations of safety net burden with key clinical outcomes. RESULTS Of an estimated 8,941,334 hospitalizations with a primary diagnosis of acute respiratory failure, 33.9% were categorized at low burden hospitals (LBH) and 31.6% at high burden hospitals (HBH). In-hospital mortality significantly decreased at HBH (22.8%-12.6%, nptrend<0.001) and LBH (22.0%-10.9%, nptrend<0.001) over the study period, as did tracheostomy placement (HBH: 5.6%-1.3%, LBH: 3.5%-0.8%, all nptrend<0.001). After adjustment for patient and hospital factors, HBH was associated with increased odds of mortality (AOR: 1.11, 95% CI: 1.10-1.12) and tracheostomy use (AOR: 1.33, 95% CI: 1.29-1.37), as well as greater hospitalization costs (β: +$1,083, 95% CI: 882-1,294) and longer lengths of stay (β: +3.3 days, 95% CI: 3.2-3.3). INTERPRETATION After accounting for differences between patient cohorts, high safety net burden was independently associated with inferior clinical outcomes and increased costs following acute respiratory failure hospitalizations. These findings emphasize the need for healthcare reform in order to ameliorate disparities within these safety net centers, which treat our most vulnerable populations.