The Division of Pulmonary, Critical Care, and Sleep Medicine runs a full service pulmonary physiology laboratory. We perform resting pulmonary function studies including spirometry, lung volumes (nitrogen washout and plethysmography), diffusing capacity, arterial blood gasses and bronchoprovocation with methacholine. We also perform exercise studies including complete cardiopulmonary exercise testing (measuring the interaction of the heart, lungs and body), desaturation studies (measuring blood oxygenation with exercise), and 6- minute walk tests. These studies are very helpful in determining the cause and severity of breathing difficulties, work capacity, and fitness, especially as they relate to disability. These studies are also important in the exercise prescriptions used in our pulmonary rehabilitation program. The Laboratory Supervisor is Moises Ortega, RCPFT, RMLT. We have three pulmonary physiology technicians: Audrey Brown, CMLT, Jocelyne O'Keefe, CMLT, CPFT and Thelapilly Skariya, CRTT, CPFT. The medical Director is William Clapp, MD. Our main laboratory is in Clinic T, on the 2nd floor at John H. Stroger Jr. Hospital of Cook County, 1901 West Harrison Street, Chicago, IL 60612. Our main phone number is 312-964-2900. We have satellite laboratories at Provident Hospital of Cook County and at Oak Forest Hospital of Cook County.