- Patients must not have, at the time of registration, uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, or psychiatric illness/social situations that would limit compliance with study requirements; furthermore, since hypoxemia may cause serious adverse events in persons with serious cardiac and/or pulmonary disease, patients at the time of registration with a history of myocardial infarction within the prior 6 months, or with symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia requiring medical intervention (with the exception of chronic, stable, asymptomatic atrial fibrillation), or pulmonary disease requiring oxygen are excluded