Clinical factors associated with the use of NIV in the pre-hospital setting in adult patients treated for acute COPD exacerbation: a single-center retrospective cohort study.

Background: Non-invasive ventilation (NIV) is a cornerstone in the management of acute chronic obstructive pulmonary disease (COPD) exacerbations with respiratory failure. While extensively studied in hospital settings, limited data exist on its use in the pre-hospital setting and clinical factors influencing its application. This study aimed to identify predictors of NIV use in the pre-hospital setting and to assess its association with patient-centered outcomes.

Methods: This single-center retrospective cohort study analyzed data from a pre-hospital emergency medical service registry in Geneva, Switzerland. Adult patients with a presumptive diagnosis of acute COPD exacerbation were included, spanning a control period (2007-2010, before NIV implementation) and an intervention period (2013-2017, after NIV implementation). For the primary analysis, multivariable logistic regression was used to identify predictors of NIV use during the intervention period. For the secondary analysis, coarsened exact matching balanced patients treated with NIV during the intervention period with those from the control period, followed by conditional regression analyses to assess patient-centered outcomes.

Results: Among 270 included patients, 84 (46%) received NIV during the intervention period. Age ≥ 70 years (aOR 2.49, 95% CI 1.11, 5.76), female sex (aOR 2.48, 95% CI 1.13, 5.60), and systolic blood pressure (SBP) ≥ 140 mmHg (aOR 2.75, 95% CI 1.19, 6.62) were independent predictors associated with receiving NIV in the pre-hospital setting. In the matched cohort, pre-hospital NIV use was significantly associated with increased ICU admission rates, but was not associated with transport time, emergency department length of stay, hospital length of stay, or 28-day mortality. Sensitivity analyses demonstrated consistent results across different modeling approaches.

Conclusions: Age ≥ 70 years, female sex, and SBP ≥ 140 mmHg were independent predictors associated with receiving NIV in the pre-hospital management of acute COPD exacerbation. The association between NIV use and increased ICU admissions may reflect its application in more severely ill patients. Pre-hospital NIV was not associated with short- or long-term outcomes beyond ICU admission. These findings underscore the need for prospective studies to clarify the role of pre-hospital NIV in patient outcomes.