PREDICTORS OF OUTCOME OF NONINVASIVE VENTILATION IN SEVERE COPD EXACERBATION

Background: Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. Acute exacerbation of COPD (AECOPD) often leads to respiratory failure requiring ventilatory support. Non-invasive ventilation (NIV) has emerged as an effective treatment strategy, but factors predicting its outcome remain inadequately understood. This study aimed to identify factors that predict NIV outcomes in patients with AECOPD and explore determinants of NIV settings and duration. Methodology: A hospital-based prospective cohort study was conducted at the Department of Respiratory Medicine, Jaipur National University Hospital, Rajasthan, India. Sixty patients with AECOPD requiring NIV were enrolled. Clinical parameters, arterial blood gas (ABG) analyses and ventilator settings were recorded at baseline and at multiple intervals during treatment. Outcomes were categorized as "success" (clinical stability allowing ward transfer) or "failure" (worsening respiratory parameters requiring intubation or resulting in death). Results: Of the 60 patients, 43 (71.7%) responded successfully to NIV. Baseline demographic and clinical characteristics were comparable between success and failure groups. However, significant improvements in pH (p=0.013), PaCO₂ (p=0.007) and PaO₂ (p=0.018) were observed in the success group after just 2 hours of NIV therapy with continued improvement in subsequent measurements. The mean duration of NIV treatment was significantly longer in the success group (2.69±3.80 days) compared to the failure group (0.92±1.41 days, p=0.018). Commonly observed complications included dryness of oral and nasal mucosa (30%), eye irritation (20%) and skin abrasion (13.3%). Conclusion: Early improvement in arterial blood gas parameters, particularly pH, PaCO₂ and PaO₂ within the first 2 hours of NIV initiation, strongly predicts successful outcomes in AECOPD patients. Regular monitoring of these parameters may help identify patients who would benefit from continued NIV support versus those requiring escalation to invasive ventilation.