Vasopressors are medications that are given intravenously to increase the blood pressure of patients with illnesses that cause dangerous blood pressure drops. When a doctor prescribes a vasopressor, they ask that the dose be adjusted to achieve a specific blood pressure. This kind of medical support with intravenous (IV) vasopressors are usual treatments in intensive care unit (ICU) settings. Oral vasopressors, such as midodrine, have been historically used to maintain blood pressure in non-critically ill patients. In this study, the investigators will be using midodrine to reduce the need for IV vasopressors as blood pressure improves during the stay in the ICU. This LIBERATE multi-site study will continue the work of the LIBERATE feasibility RCT study to evaluate the role of midodrine for patients with low blood pressure in the ICU. It is comprised of the multi centre pilot RCT followed by the definitive multi centre RCT.