Non-invasive Venous Air Plethysmography Assessment of Venous Hemodynamics in Patients Suspected Deep Venous Obstruction Used in Conjunction With Intermittent Pneumatic Compression.

The purpose of this research is to measure changes in venous blood flow with an air-filled bladder under an intermittent pneumatic compression device cuff (used to prevent deep venous thrombosis) or venous diagnostic device cuff (used to detect deep venous thrombosis). The devices being used in the study are investigational and not FDA-cleared.