Patients participating in the underlying GUARDIAN trial (NCT04884802) will be randomized to: 1) norepinephrine or phenylephrine infusion to maintain intraoperative MAP ≥85 mmHg, delayed resumption of chronic antihypertensive medications, and a target ward systolic pressure of at least 110 mmHg (tight pressure management); or, 2) routine intraoperative blood pressure management and prompt resumption of chronic antihypertensive medications (routine pressure management). Patients participating in this sub-study will be additionally randomized to norepinephrine or phenylephrine infusion to maintain the designated target intraoperative mean arterial pressure.
Some patients participating in the underlying GUARDIAN trial (NCT04884802) will be additionally randomized to norepinephrine or phenylephrine infusion to maintain the designated target intraoperative mean arterial pressure.