Predicting in-hospital mortality in a real-world population of ward-based non-invasive ventilation in acute COPD exacerbations

Abstract

Background: Accurate tools for patient stratification by likely outcome are needed to support complex decision-making and improve acute non-invasive ventilation (NIV) delivery. Objectives: To evaluate the potential of an emerging NIV outcomes (NIVO) score tool to predict in-hospital mortality to aid its validation in a real-world UK hospital population of ward-based NIV for acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Design: This was a retrospective observational cohort study of all consecutive patient admissions with AECOPD managed with NIV for acute hypercapnic respiratory failure at a teaching hospital. Methods: Clinical parameters were collected as part of an ongoing quality improvement project. Patients were grouped based on their survival status at hospital discharge. First admission of each patient was included in the analysis. NIV failure, defined as NIV withdrawal or intubation requirement due to clinical deterioration on NIV, along with in-hospital mortality, was modelled using logistic regression. Results: There were 249 unique patient AECOPD admissions with ward-based NIV. Across first admissions, NIV failure rate was 37.3%, in-hospital mortality 26.5%, and 1-year mortality 47.0%. NIVO score was significantly associated with both NIV failure and in-hospital mortality, with odds ratios (95% Confidence intervals) of 1.33 (1.13–1.58, p < 0.001) and 1.52 (1.26–1.86), p < 0.001, respectively. A progressive increase in in-hospital mortality was observed with increasing NIVO scores (p < 0.0001). Conclusion: This study demonstrates that the NIVO score shows promise as a predictive tool for in-hospital mortality in patients with AECOPD receiving ward-based NIV. Furthermore, it suggests that NIVO may be able to support decision-making for enhanced NIV delivery in new clinical pathways to address the growing burden of chronic obstructive pulmonary disease exacerbations.