A Retrospective Analysis of the Effects of Time on Compliance and Driving Pressures in ARDS.

BACKGROUND: The evolution of compliance and driving pressure in ARDS and the effects of time spent on noninvasive respiratory support prior to intubation have not been well studied. We conducted this study to assess the effect of the duration of noninvasive respiratory support prior to intubation (ie, noninvasive ventilation [NIV], high-flow nasal cannula [HFNC], or a combination of NIV and HFNC) on static compliance and driving pressure and retrospectively describe its trajectory over time for COVID-19 and non-COVID-19 ARDS while on mechanical ventilation. METHODS: This is a retrospective analysis of prospectively collected data from one university-affiliated academic medical center, one rural magnet hospital, and 3 suburban community facilities. A total of 589 subjects were included: 55 COVID-19 positive, 137 culture positive, and 397 culture-negative subjects. Static compliance and driving pressure were calculated at each 8-h subject-ventilator assessment. RESULTS: Days of pre-intubation noninvasive respiratory support were associated with worse compliance and driving pressure but did not moderate any trajectory. COVID-19-positive subjects showed non-statistically significant worsening compliance by 0.08 units per subject-ventilator assessment (P = .24), whereas COVID-19-negative subjects who were either culture positive or negative showed statistically significant improvement (0.12 and 0.18, respectively; both P < .05); a statistically similar but inverse pattern was observed for driving pressure. CONCLUSIONS: In contrast to non-COVID-19 ARDS, COVID-19 ARDS was associated with a more ominous trajectory with no improvement in static compliance or driving pressures. Though there was no association between days of pre-intubation noninvasive respiratory support and mortality, its use was associated with worse overall compliance and driving pressure.

Implementation of High-Flow Nasal Cannula Therapy Outside the Intensive Care Setting.

BACKGROUND: High-flow nasal cannula (HFNC) is an option for respiratory support in patients with acute hypoxic respiratory failure. To improve patient outcomes, reduce ICU-associated costs, and ease ICU bed availability, a multi-phased, comprehensive strategy was implemented to make HFNC available outside the ICU under the supervision of pulmonology or trauma providers in cooperation with a dedicated respiratory therapy team. The purpose of this study was to describe the education and implementation process for initiating HFNC therapy outside the ICU and to convey key patient demographics and outcomes from the implementation period. METHODS: HFNC therapy was implemented at a tertiary hospital in the Midwest, with systematic roll-out to all in-patient floors over a 9-month period. Utilization of the therapy and patient outcomes were tracked to ensure safety and efficacy of the effort. RESULTS: During the implementation period, 346 unique subjects met study inclusion criteria. Median (interquartile range) hospital length of stay was 8 d (4-12), and median duration of HFNC therapy was 44 h (18-90). Two thirds of subjects (n = 238) received the entire course of HFNC therapy outside the ICU, and more than half of subjects (n = 184) avoided the ICU for their entire hospitalization. Moreover, 6% of subjects in the study group escalated from HFNC to noninvasive ventilation, and 5% of subjects escalated from HFNC to mechanical ventilation. CONCLUSIONS: A comprehensive implementation process and a robust therapy protocol were integral to initiating and managing HFNC in all hospital locations. Study findings indicate that patients with acute hypoxic respiratory failure can safely receive HFNC therapy outside the ICU with appropriate patient selection and staff education.