Noninvasive Mechanical Ventilation Failure and Long-Term Follow-up Results of Failure in Hypercarbic Respiratory Failure

Aim: Use of noninvasive mechanical ventilation (NIMV) in acute respiratory failure has been an important option. The aim of this study is to evaluate causes of NIMV failure and follow-up results in hypercarbic respiratory failure (HRF). Material and Methods: Retrospective observational cohort study was performed in intensive care unit of tertiary chest disease hospital. All patients with NIMV failure due to HRF between January-December 2016 were included in the study. Demographic characteristics, intensive care data and mortality were evaluated in early and late NIMV failure groups. Appropriate statistical tests and analyzes were used for analysis of data. Results: The majority of 218 patients (n=158, 72.5%) included in the study was chronic obstructive pulmonary disease. Early NIMV failure was seen 56% of cases. The most common causes of failure were progression or worsening of acidosis and increase in partial carbon dioxide pressure. Mortality was detected as 20% in intensive care unit and 9% after discharge in 28-days. Factors increased NIMV failure was found as progression of acidosis by 4.1 fold (95% confidence interval (CI) 1.711-9.882, p=0.002), inability to protect airway by 10.4 fold (95% CI 1.224-89.264, p=0.032) and blurred consciousness by 2.3 fold (95% CI 1.023-5.295, p=0.044). Conclusion: Early NIMV failure was observed in half of cases and most common causes of failure were found as progression of acidosis and increase in partial carbon dioxide pressure. When intensive care and 28-day mortality are evaluated, it is thought that patients with NIMV failure should be followed-up closely after discharge from intensive care