NIV failure in respiratory failure: an analysis

Abstract

Abstract Objective Noninvasive ventilation (NIV) has become an increasingly accepted mode of treatment for acute respiratory failure. Concept of NIV has revolutionized the treatment of acute respiratory failure in terms of the spectrum of diseases that can be successfully managed, the locations of its application, and achievable goals. The study was aimed at analyzing various aspects of NIV failure. Material and methods In this prospective observational study, all patients who underwent NIV therapy for acute respiratory failure from September 2019 to June 2020 were recruited. The clinical, radiological, laboratory and other relevant data from patients satisfying inclusion criteria were collected and analyzed using appropriate statistical tools. Results Out of the 96 NIV applications, 19 (19.8%) failed NIV application in the form of intubation in 12 and in-hospital mortality in 8 (8.3% of the total group). A total of 73.7% (14/19) had an early failure, and 26.3% (5/19) had late failure. The median length of hospital stay was significantly higher in NIV failure group compared to NIV success group (p < 0.001). NIV outcomes like failure rate, in-hospital mortality, and length of hospital stay did not have any difference between type 1 and type 2 ARF (p > 0.05). NIV failure and in-hospital mortality were found to be higher in patients with pneumonia and ILD group, respectively (p < 0.05). A baseline respiratory rate of more than 37 per minute, pH < 7.28, and pCO2 > 77 mm Hg measured 1–2 h after NIV initiation, hyponatremia, and prior NIV failure history were identified as the independent predictors of NIV failure. Using NIV as a treatment modality in respiratory failure secondary to pneumonia has more chances of failure (p < 0.05). Conclusion Though NIV is the preferred initial tool in the management of respiratory failure, it should be judiciously used when risk factors for failure are present. Early escalation or upfront use of invasive mechanical ventilation should be considered in such scenario to prevent undue mortality and morbidity in respiratory failure patients. Main points • Key point behind successful expansion of NIV is its capacity to achieve the same clinical outcomes as invasive ventilation with the avoidance of the complications associated with it. • Delay in identifying the patients who are likely to fail NIV can cause undue delay in intubation; this can lead to clinical deterioration and increased morbidity and mortality. • Predictors of NIV failure deciphered from this study are prior history of invasive mechanical ventilation following NIV failure, higher baseline respiratory rate, hyponatremia, low pH, and hypercapnia despite 1–2 h of NIV.