Outcome at three months of COPD patients with acute hypercapnic respiratory failure treated with NPPV in an Acute Medicine Ward

Abstract

Non invasive positive pressure ventilation (NPPV) is increasingly used for patients with hypercapnic respiratory failure secondary to acute exacerbation of chronic obstructive pulmonary disease (COPD). NPPV has been shown to improve arterial blood gas tensions and dyspnoea and to prevent the need for intubation in patients admitted to hospital with an exacerbation of COPD associated with respiratory acidosis. Although advantages of NPPV over conventional treatment have been convincingly documented in the short period, there are fewer data as to the outcomes following hospital discharge. We have undertaken a prospective descriptive study to obtain comprehensive data on the in hospital and 3 month outcomes of a cohort of 57 COPD patients treated with NPPV for acute hypercapnic respiratory failure as a first intervention in addition to usual medical care. Patients with a COPD exacerbation had better outcomes than patients with COPD complicated by other acute conditions. Pneumonia was specifically associated with a higher inhospital risk of death. In our series about one in four patients with an indicator of previous severe respiratory disease (past admission for acute respiratory failure, previous use of NPPV, long term oxygen therapy or home NPPV) was dead at three months after discharge and almost one in two was dead or had been readmitted. On the contrary, patients without indicators of previous severe respiratory disease benefited from NPPV during an acute episode of respiratory failure and had a chance of approximately 80% of being alive and free from recurrence at three months.