Hypertensive Emergencies and Urgencies

1

What is a hypertensive emergency?

A hypertensive emergency refers to large elevations in systolic and/or diastolic blood pressure with impending or progressive, acute, end-organ damage. The systolic blood pressure is usually 180 mm Hg or higher and/or diastolic blood pressure 120 mm Hg or higher.

This definition implies that hospitalization for intravenous medication is required and that altering the blood pressure will improve end-organ damage. In-hospital mortality is estimated at 0.2% to 11%.

2

Why do hypertensive emergencies happen?

The most common reason is nonadherence to blood pressure–lowering medication. Greater than 70% of patients diagnosed with a hypertensive emergency in the emergency room have previously diagnosed hypertension and have been prescribed medications. Common associations include a previous history of hypertension; being an elderly, non-White man; a lack of a primary care practitioner, and cocaine use.

3

What is a hypertensive urgency and how does this differ from a hypertensive emergency?

The definition is the same as that for an emergency but there is NO acute end-organ involvement. The absolute level of blood pressure does not distinguish an emergency from an urgency as blood pressure thresholds are different in children and pregnant women, among whom sudden, modest increases in blood pressure can cause severe vascular injury.

There is a poor correlation between symptoms and the presence of a hypertensive emergency. Patients with chronic hypertension may be asymptomatic with a blood pressure of 220/140 mm Hg. So a hypertensive urgency might not differ from asymptomatic hypertension, and it is important to try to rule out the “acute recognition” of chronic hypertension.