HFNCThe Simplify Project

The high frequency of unplanned hospital visits of patients with chronic hypercapnic respiratory failure (e.g., chronic obstructive pulmonary disease, obesity-related hypoventilation) constitutes a major public health problem. Most patients admitted for acute exacerbations (AHRF) have additional comorbidities, especially sleep disorders. Often untreated, sleep disorders contribute to multiple readmissions (≈70% at one year) and increase readmission costs. The investigators will: 1) identify these patients early during unplanned hospital admissions and perform sleep studies using EEG and oximetry before hospital discharge and two months after to compare sleep abnormalities in the two moments; 2) investigate the association between sleep abnormalities in the two sleep studies with clinical outcomes (1-year readmission and death); 3) investigate the acute effects of high-flow nasal cannula (HFNC) to treat sleep abnormalities as a simplified alternative. The investigators anticipate sleep abnormalities during the hospital stay and two months after discharge will be associated with poor clinical outcomes (readmission, death) and HFNC to acutely reduce sleep abnormalities.