Outcomes and predictors of success of noninvasive ventilation in acute exacerbation of chronic obstructive pulmonary disease

Abstract

Abstract Background Noninvasive ventilation is appropriately used as a first-line treatment of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) in many emergency departments. It has been evaluated in a large number of trials, often with clinically important benefits, but the use of noninvasive positive pressure ventilation remains highly variable across institutions and geographical regions. The aim of the study was first to emphasize the superiority of noninvasive ventilation (NIV) in acute hypercapneic respiratory failure in patients with an AECOPD in comparison with conventional therapy alone and second was to identify the predictors of NIV failure in such patients. Patients and methods A total of 50 patients were randomly allocated into two equal groups: 25 patients subjected to medical and oxygen therapy (group I) and 25 to medical and NIV (group II). All patients were followed until death or discharge. Results Group II had a success rate (for weaning and discharge) of 76%, whereas in group I, it was 20% (odds ratio=0.0789, 95% confidence interval=0.021–0.302 and P<0.001). Hospital stay was significantly longer in group I. Complications were significantly higher in group I. Mortality was significantly higher in group I. Improvement of arterial blood gases, respiratory rate, dyspnea scores and hypercarbic encephalopathy was significantly better in non-invasive positive pressure ventilation (NIPPV) group. Conclusion The addition of NIPPV to standard therapy confers more benefits in patients with AECOPD, with significant reduction of in-hospital mortality, rate of endotracheal intubation, incidence of complications and length of hospital stay compared with standard therapy alone. On the contrary, failure can be predicted by the presence of more comorbidities, signs of severe exacerbation, high BMI, high baseline blood sugar, rapid respiratory rate at admission, abnormal baseline renal functions, high baseline C-reactive protein, high baseline acute physiology and chronic health evaluation II and BAP 65: B=BUN; A=Altered mental status; P=Pulse rate; 65-age years (BAP 65) scores, severe acidosis before NIV treatment and persistent severe acidosis after 1 h of treatment.

Keywords

• acute exacerbations of chronic obstructive pulmonary disease
• acute hypercapnic respiratory failure
• NIPPV