Hypertensive emergencies

Abstract

Elevated blood pressure is common in the intensive care unit setting and may be the reason for the admission of certain patients or develop in patients who are already hospitalized. It can manifest as an emergency, requiring prompt reduction of blood pressure with intravenous agents, or as urgency, where blood pressure control can be done more gradually with oral agents. The fact that differentiates these two situations is the presence of target organ damage, found in hypertensive emergencies, leading to findings mainly neurological (hypertensive encephalopathy, ischemic stroke or intracerebral hemorrhage), hematologic (microangiopathic hemolysis), cardiovascular (acute left ventricular failure, myocardial ischemia and infarction and aortic dissection), or renal (oliguria, azotemia). The hypertensive emergencies can also arise in postoperative or associated with elevation of catecholamines and eclampsia. The initial approach includes the patient’s history and physical examination, looking for information such as the presence of preexisting hypertension, prior comorbidity and manifestations related to target organ damage. Additional exams are also needed, such as laboratory tests and imaging studies in search of target organ damage. Because of the morbidity and mortality associated with these situations, blood pressure should be controlled quickly with intravenous agents. Initial therapy aims to reverse the target organ damage and does not return to normal blood pressure. Subsequently oral agents can be introduced. The choice and the goals of treatment are based on consensus and should be guided by the etiology of hypertension, extent of target organ damage and hemodynamic profile of the individual patient.