Noninvasive ventilation in patients with acute hypercapnic exacerbation of chronic obstructive pulmonary disease who refused endotracheal intubation

OBJECTIVE: To determine the long-term outcome of noninvasive ventilation in chronic obstructive pulmonary disease patients who refused intubation for acute hypercapnic respiratory failure. DESIGN: Prospective, observational study. SETTING: Noninvasive ventilation unit in an acute regional hospital in Hong Kong. METHODS: The study recruited 37 chronic obstructive pulmonary disease patients who had the do-not-intubate code and developed acute hypercapnic respiratory failure. They were offered noninvasive ventilation, and their long-term outcomes were followed. Survival and event-free survival (an event is death or recurrent acute hypercapnic respiratory failure) were analyzed by survival analysis. Their disease profile and outcome were compared with another 43 chronic obstructive pulmonary disease patients without the do-not-intubate codes, who had acute hypercapnic respiratory failure and received noninvasive ventilation during the study period (usual care group). RESULTS: Patients in the do-not-intubate group were significantly older (p =.029), had worse dyspnea score (p <.001), worse Katz Activities of Daily Living score (p <.001), worse comorbidity score (p =.024), worse Acute Physiology and Chronic Health Evaluation II score (p =.032), lower hemoglobin (p =.001), and longer stay in the hospital during the past year (p =.001) than patients who received usual care. In the do-not-intubate group, the median survival was 179 days, and 1-yr actuarial survival was 29.7%; in the usual care group, the median survival was not reached during follow-up, and 1-yr actuarial survival was 65.1% (p <.0001). In the do-not-intubate group, the median event-free survival was 102 days, and 1-yr event-free survival was 16.2%; in the usual care group, median event-free survival was 292 days, and 1-yr event-free survival was 46.5% (p =.0004). CONCLUSIONS: A 1-yr survival of about 30% was recorded in chronic obstructive pulmonary disease patients with the do-not-intubate code who developed acute hypercapnic respiratory failure requiring noninvasive ventilation. The majority of survivors developed another life-threatening event in the following year. Information generated from this study is important to physicians and chronic obstructive pulmonary disease patients when they are considering using noninvasive ventilation as a last resort.