Perioperative hypertensive emergencies.

The concept of "perioperative hypertensive emergency" must be defined differently from that of ambulatory hypertensive emergency in view of its unique clinical considerations in an atypical setting. It should be noted that moderately high normal blood pressure (BP) values in the perioperative setting often trigger situations requiring immediate treatment in what would otherwise be a "BP-acceptable" non-surgical condition. Commonly recognized circumstances that may result in a perioperative hypertensive emergency include exacerbation of severe mitral insufficiency, hypertension resulting in acute decompensated heart failure, hypertension caused by acute catecholamine excess, rebound hypertension after withdrawal of antihypertensive medications, hypertension resulting in bleeding from vascular surgery suture lines, intracerebral hemorrhage, aortic dissection, hypertension associated with preeclampsia, and hypertension associated with autonomic dysreflexia. In addition, perioperative BP lability has been reported to increase the risk for stroke, acute kidney injury, and 30-day mortality in patients undergoing cardiac surgery.