Epidemiology and Outcomes of Invasive Mechanical Ventilation Without ICU Admission in Acute Care Hospitals in Texas: A Population-based Cohort Study

Purpose: The high ICU bed capacity in the United States (US) allows ICU care of patients requiring invasive mechanical ventilation (IMV), absent public health crisis. The use of IMV without ICU admission (non-ICU) in acute care hospitals in the US and its impact on patients' outcomes were not examined.

Methods: A retrospective cohort study was performed using statewide inpatient data in Texas to identify hospitalizations aged ≥18 years receiving IMV in acute care hospitals with ICU care capability during January 2014 through September 2015. Use of non-ICU IMV, patient characteristics, and hospital mortality were examined.

Results: Among 136,728 IMV hospitalizations, 4531 (3.3%) were non-ICU. As compared to ICU admissions, non-ICU IMV hospitalizations were younger (age 18-44 years: 24.9% vs. 17.2%), with lower burden of major comorbidities (no major comorbidity: 24.7% vs. 14.5%), and lower occurrence of non-respiratory organ failures (no non-respiratory organ failure: 32.7% vs. 19.8%). Risk-adjusted hospital mortality of non-ICU vs. ICU IMV hospitalizations was 48.7% (95% CI 48.1-49.4) and 29.9% (95% CI 29.8-30.0), respectively.

Conclusions: Non-ICU IMV was provided in 1 in 30 IMV hospitalizations in acute care hospitals. Although non-ICU IMV hospitalizations were younger and healthier than those admitted to ICU, their hospital mortality was markedly higher.