A worldwide assessment of the mechanical ventilation in patients with acute exacerbations of chronic obstructive pulmonary disease. Analysis of the VENTILAGROUP over time. A retrospective, multicenter study

Abstract

Background: The trend over time and across different geographical areas of outcomes and management with noninvasive ventilation or invasive mechanical ventilation in patients admitted for acute exacerbations of chronic obstructive pulmonary disease and treated with ventilatory support is unknown. The purpose of this study was to describe outcomes and identify variables associated with survival for patients admitted to an intensive care unit (ICU) with acute exacerbation of chronic obstructive pulmonary disease [aeCOPD] who received noninvasive or invasive mechanical ventilation worldwide.

Methods: Retrospective, multi-national, and multicenter studies, including four observational cohort studies, were carried out in 1998, 2004, 2010, and 2016 for the VENTILAGROUP following the same methodology.

Results: A total of 1,848 patients from 1,253 ICUs in 38 countries admitted for aeCOPD and need of ventilatory support were identified in the four study cohorts and included in the study. The overall incidence of aeCOPD as a cause for ventilatory support at ICU admission significantly decreased over time and varied widely according to the gross national income. The mortality of patients admitted to ICU for aeCOPD and ventilatory support significantly decreased over time regardless of the geographical area and gross national income; however, there is a remarkable variability in ICU mortality according to geographical area and gross national income. The use of NPPV as the first attempt at ventilatory support has significantly increased over time, with a parallel reduction of invasive mechanical ventilation regardless of gross national income.

Conclusion: In this worldwide observational study, including four sequential cohorts of patients over 18 years from 1998 to 2016, the mortality of patients admitted to ICU for aeCOPD and ventilatory support significantly decreased regardless of the geographical area and gross national income. Future research will need to investigate the reason for the remarkable variability in ICU mortality according to the geographical area, gross national income, and methods to select patients for the appropriate ventilatory support.

Keywords: Chronic obstructive pulmonary disease; Exacerbation; Mechanical ventilation; Mortality.

Fig. 1

Bar chart of the frequency (incidence rate) showing the first ventilatory support in aeCOPD critically ill patients at ICU admission over time. # p < 0.001 versus period 1998; *# p < 0.001 versus period 1998. Abbreviation: NPPV, noninvasive positive pressure ventilation (reference 28)

Fig. 2

Box plot panel describing the arterial blood gas parameters during the first days of ventilator support including all patients from the four studies: a, pH values; b, PaCO₂; c, PaO₂/FiO₂ ratio. In the box plot, the median (dark line inside the box), quartiles 1 and 3 (box edges), minimum and maximum (whisker ends), and outliers (points beyond 1.5 × IQR) are shown

Fig. 3

Forest plot for the prediction of poor outcomes in aeCOPD patients. A ICU mortality; B prolonged invasive mechanical ventilation on day 3; C mortality in patients receiving invasive mechanical ventilation as competitive outcome for patients with prolonged invasive mechanical ventilacion (longer or equal to 14 days). Abbreviations: SAPSII: Simplified Acute Physiology Score. X-axes are represented in a logarithmic scale