A prospective observational study to determine the predictors of failure of non-invasive ventilation in patients with type 2 respiratory failure

Abstract

Background: This study aims to evaluate clinical and biochemical parameters likely to predict the failure of non-invasive ventilation (NIV) in patients with type 2 respiratory failure. Methods: The study was conducted from September 2016 to August 2018. Clinical and biochemical parameters of 151 patients were analysed after the application of NIV and divided into two groups, success group if they remained on NIV after 48 h and failure group if intubated. Results: Among 151 patients, 65 patients (43%) were intubated and included in the failure group. The remaining 86 patients (57%) were included in the success group. Of the 65 patients who got intubated, 16 patients died while 49 recovered. Out of the 151 patients enrolled the gender distribution was 65 males and 86 females. There was no statistically significant association of the outcome of NIV usage with the comorbidity of the patient and with the underlying lung pathology of the patient. Seventy-two per cent (47 patients) of the NIV failures were in the first 6 h. Lower pH, higher partial pressure of carbon dioxide, higher heart rate and respiratory rate (RR) at baseline showed a statistically significant association with the failure of NIV usage in patients with type 2 respiratory failure. Failure of clinical and biochemical parameters to improve at various time points was also associated with increased chances of failure of NIV usage. Conclusions: Linear regression analysis showed that pH and RR at baseline and presence of severe pulmonary artery hypertension were found to be predictors of failure of NIV.