A hypertensive crisis is a rapid and marked elevation in blood pressure, with systolic values exceeding 180 mmHg and diastolic values above 120 mmHg. If not managed properly, it can cause acute organ damage affecting the brain, heart, kidneys, and vasculature, requiring urgent or emergency medical intervention.
Hypertensive urgency is characterised by a significant increase in blood pressure without evidence of acute organ damage. The patient may experience symptoms such as pulsating headache, visual disturbances, tachycardia, dyspnoea, and tinnitus. However, there are no signs of immediate organ compromise. Blood pressure should be reduced gradually over 24-48 hours to avoid the risk of cerebral and renal hypoperfusion.
Conversely, hypertensive emergency occurs when blood pressure reaches critical levels, exceeding 220/140 mmHg, and leads to acute organ damage, with potential complications such as ischaemic or haemorrhagic stroke, myocardial infarction, pulmonary oedema, aortic dissection and acute renal failure. In these cases, it is necessary to lower blood pressure rapidly with intravenous medications.
Hypertensive crisis can be triggered by various factors, including non-adherence to antihypertensive therapy, which can result in sudden increases in blood pressure. Acute pathological conditions, such as renal failure or endocrinopathies (for example, pheochromocytoma), may also precipitate severe hypertensive episodes. Factors such as intense stress, use of sympathomimetic substances (cocaine, amphetamines), or preeclampsia during pregnancy further contribute to the onset of the crisis.
Clinical Manifestations
Symptoms vary depending on the degree of blood pressure elevation and whether organ involvement is present.
The patient may report a severe headache, often occipital, associated with visual disturbances and mental confusion.
In more severe cases, chest pain, dyspnoea and neurological signs may appear, the latter being indicative of ongoing cerebral damage.
Some patients may present with epistaxis (nosebleed), a sign of extremely high blood pressure.
Hypertensive crises can cause irreversible damage to target organs.
At the cerebral level, elevated pressure can lead to ischaemic or haemorrhagic stroke, with permanent neurological deficits. The heart may develop myocardial infarction or acute heart failure, while the kidneys may sustain ischaemic injury progressing to acute renal failure. The retina may be involved with papilledema and retinal haemorrhages.
Management of Hypertensive Crisis
The management of hypertensive crisis depends on the presence or absence of acute organ damage:
Hypertensive urgency (not associated with acute organ damage):
Gradual blood pressure control with oral antihypertensive agents: blood pressure should be reduced over 24-48 hours to avoid cerebral and renal hypoperfusion. ACE inhibitors (captopril, enalapril), calcium channel blockers (amlodipine, slow-release nifedipine), and beta-blockers (labetalol, metoprolol) are used, chosen according to the patient’s clinical status.
Optimisation of long-term antihypertensive therapy: after initial crisis control, it is essential to adjust maintenance treatment to prevent recurrences, combining multiple drug classes and regularly monitoring blood pressure.
Hypertensive emergency (associated with acute organ damage): immediate treatment with parenteral medications is required:
Vasodilators such as sodium nitroprusside, which rapidly lowers blood pressure.
Nitroglycerin, used in patients with associated myocardial ischaemia.
Beta-blockers such as labetalol, particularly effective in hypertensive emergencies.
Phentolamine, indicated for hypertensive crises secondary to pheochromocytoma.
Prevention
To reduce the risk of hypertensive crisis, it is essential to:
Carefully follow the prescribed antihypertensive therapy and not discontinue medications abruptly.
Regularly monitor blood pressure and consult your physician if persistently elevated values are detected.
Adopt a healthy lifestyle, with a low-sodium diet, regular physical activity, and weight control.
Avoid the use of substances that can induce severe hypertension, such as alcohol and stimulant drugs.
Conclusion
Hypertensive crisis is a serious clinical condition requiring immediate attention. Early recognition of symptoms and appropriate management are essential to prevent irreversible organ damage. Long-term blood pressure control and optimal management of risk factors can significantly reduce the risk of recurrence and complications.
References
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