Lung disease besides COPD (e.g., pulmonary fibrosis, bronchiectasis, pulmonary arterial hypertension) other than well controlled asthma

Unrevascularized coronary artery disease, angina, prior heart attack or stroke, congestive heart failure

Uncontrolled hypertension (SBP \>160, DBP \>95)

Unwilling or unable to withhold CPAP during polysomnography

Presence of tracheostomy

Hospitalization within the past 90 days

Prior peptic ulcer disease, esophageal varicies, or gastrointestinal bleeding (\< 5 years)

Prior gastric bypass surgery

Anticoagulant use (other than aspirin) or bleeding diathesis (only for esophageal catheter placement)

Chronic liver disease or end-stage kidney disease

Allergy to any of the study medications

Regular use of medications known to affect control of breathing (opioids, benzodiazepines, theophylline)

Insomnia or circadian rhythm disorder

Active illicit substance use or \>3 oz nightly alcohol use

Psychiatric disease, other than controlled depression

Pregnancy

Prisoners

Cognitive impairment, unable to provide consent, or unable to carry out research procedures

Impact of Non-invasive Ventilation in Hypercapnic COPD