From the Guidelines
Systolic blood pressure (SBP) above 200 mmHg is considered an acute problem when it's accompanied by signs of end-organ damage, which constitutes a hypertensive emergency requiring immediate intervention, as indicated by the 2024 ESC guidelines for the management of elevated blood pressure and hypertension 1. This includes symptoms such as severe headache, visual disturbances, chest pain, shortness of breath, neurological deficits, altered mental status, or evidence of acute kidney injury.
- Key symptoms of hypertensive emergency depend on the organs affected and may include:
- Headache
- Visual disturbances
- Chest pain
- Shortness of breath
- Dizziness
- Neurological deficits
- Without these symptoms, it's classified as a hypertensive urgency, which still requires prompt attention but is less immediately life-threatening. For hypertensive emergencies, intravenous medications like labetalol, nicardipine, or clevidipine are recommended to lower blood pressure by no more than 25% within the first hour to avoid hypoperfusion complications 1.
- The recommended initial doses and titration rates for these medications are:
- Labetalol: initial dose 20mg IV, followed by 20-80mg every 10 minutes as needed
- Nicardipine: initial rate 5mg/hour, increased by 2.5mg/hour every 5-15 minutes
- Clevidipine: 1-2mg/hour initially, doubled every 90 seconds as needed For hypertensive urgency, oral medications like captopril, labetalol, or amlodipine can be used with close monitoring 1.
- The recommended doses for these medications are:
- Captopril: 25mg
- Labetalol: 200-400mg
- Amlodipine: 10mg The danger of severely elevated blood pressure lies in its potential to cause vascular damage, leading to stroke, myocardial infarction, acute heart failure, aortic dissection, or renal failure through mechanisms of increased vascular resistance, endothelial damage, and activation of inflammatory pathways 1.
From the Research
Definition of Hypertensive Crisis
A systolic blood pressure (SBP) greater than 200 millimeters of mercury (mmHg) is considered an acute problem when it is associated with acute end-organ damage, such as cardiovascular, cerebrovascular, or renal damage 2, 3.
Hypertensive Emergency vs. Urgency
- Hypertensive emergency: a sudden elevation in SBP and/or diastolic blood pressure (DBP) that is associated with acute end-organ damage, requiring immediate reduction in blood pressure with intravenous antihypertensive agents 2, 3.
- Hypertensive urgency: an acute elevation in SBP and/or DBP not associated with evidence of end-organ damage, which can be treated with oral antihypertensive agents within 24-48 hours 2, 3.
Management of Severe Asymptomatic Hypertension
Patients with severely elevated blood pressure (i.e., SBP ≥ 180 mmHg or DBP ≥ 120 mmHg) without signs or symptoms of end-organ damage do not require immediate workup or treatment (within 24 hours) 4. However, a cardiovascular risk profile is important in guiding the treatment of severe asymptomatic hypertension, and higher risk patients may benefit from more urgent and aggressive evaluation and treatment 4.
Treatment Outcomes
A study of patients presenting to the emergency department with severe hypertension (SBP ≥ 180 mmHg or DBP ≥ 120 mmHg) without evidence of acute end-organ damage found that one-year major adverse cardiovascular events (MACE) were relatively common, but discharge blood pressure was not associated with 30-day or one-year MACE 5.
Hypertensive Emergency and Asymptomatic Severe Hypertension
Hypertensive emergency occurs when the blood pressure level is severely elevated and acute organ damage is present, while asymptomatic severe hypertension refers to severely elevated blood pressure without symptoms or acute end-organ damage 6. Management of asymptomatic severe hypertension starts with long-acting antihypertensive drugs, and physicians should emphasize adherence to the drug regimen and monitor patients closely until the goal blood pressure level is achieved 6.