NIV for acute respiratory failure: The role of patient selection in hospital mortality

Introduction Hospital mortality among COPD patients receiving NIV for acute respiratory failure has shown to be significantly higher in clinical settings than in randomized trials in highly selected patients. This may be caused by low quality care and/or use of NIV for patients with terminal pulmonary disease with a do-not-intubate (DNI) and a do-not-resuscitate (DNR) order. Objectives The aim of this study was to determine the role of patient selection for in-hospital mortality among patients receiving NIV for acute respiratory failure. Methods Retrospective study including all patients receiving acute NIV due to COPD and acute respiratory failure on a respiratory ward in 2012. Results Thirty-nine of 68 patients (57%) had a DNI/DNR order. Overall in-hospital mortality rate was 35%. Thirty-day mortality rate was 41% and 1 year mortality rate was 56%. Average age at admission was 74 ± 12 years and average pH after initial treatment was 7.28. In-hospital mortality was 62% in 39 patients with a DNI/DNR order and 0% in 29 patients with no limitations in treatment. We identified a subgroup of 11 (28%) patients who fulfilled the inclusion criteria of the known RCT (i.e. Plant, PK et al. Lancet 2000; 355(9219):1931-5). In this subgroup in-hospital mortality rate and 30-day mortality rate were 0% and 1 year mortality rate was 18%. Average age was 68 ± 14 years and average pH was 7.31. Conclusion High total mortality reflects that patient selection in clinical practice is very different from RCT. Quality of acute NIV treatment seems acceptable in clinical practice with very low mortality in a subgroup with inclusion criteria similar to the known RCT.