Summary: The purpose of this study is to learn more about the effects of midodrine and droxidopa, two medications used for the treatment of orthostatic hypotension (low blood pressure on standing), on the veins of the abdomen of patients with autonomic failure. The study will be conducted at Vanderbilt University Medical Center, and consists of 2 parts: a screening and 2 testing days. The total length of t...

Summary: Observational two phase, retrospective and prospective registry study to assess the prevalence of and characterize outcomes of autonomic dysfunction (AD) in patients who undergo bariatric surgery (BS) and to better define the underlying pathophysiology of AD following BS.

Summary: This study tests whether a medication called droxidopa can help improve blood flow to the kidneys in people with liver cirrhosis who develop kidney problems while in the hospital. When someone with cirrhosis experiences kidney injury, having better blood pressure can help their kidneys recover. Droxidopa is an oral medication that may help raise blood pressure without requiring intensive care or i...