Predictive factors of noninvasive ventilation failure for acute exacerbation of COPD

Abstract

Introduction:Chronic obstructive pulmonary disease exacerbations (AECOPD) contribute to hospitalization, disease progression and mortality. The use of noninvasive ventilation (NIV) in patients with AECOPD and hypercapnic respiratory failure (HRF) reduces orotracheal intubation (OTI), length of stay (LOS) and mortality. Objectives:Characterize patients with EACOPD submitted to NIV and identify predictive factors of NIV failure. Methods:A retrospective analysis of patients with EACOPD submitted to in-hospital NIV in 2015-18. Clinical data, FEV1, arterial blood gas at admission (t0) and 2h after NIV onset (t2), LOS, NIV duration were recorded. Predictive factors of NIV failure (OTI or death) were analyzed. Results:A total of 179 patients (94 males, with a mean age of 78 years) were included. Of these, 58% had 1 or more COPD exacerbations in the past year, 48% underwent home oxygen therapy (O2) and 25% NIV. The mean LOS was 13 days. Mean pH at t0 was 7.31 and 7.35 at t2, and mean pCO2 (mmHg) at t0 was 69.3 and 63.8 at t2. Of the total, 46% maintained NIV at home. NIV failure was observed in 20% of cases (n=35), with death in 34 and OTI in 1. NIV failure was associated with pH and CO2 at t0 and t2, lactates at t2 and the number of exacerbations in the last year (p Conclusions:Patients with exacerbations in the last year, severe HRF at admission and a poor response after treatment have an increase in NIV failure.These results show the importance of adequate patient choice to initiate NIV. More invasive strategies may be considered in cases of poor response after 2 hours of treatment.