Hypertensive Crisis - Hypertensive Urgencies And Hypertensive Emergencies

Introduction Of Hypertensive Crisis

Hypertensive Crisis is typically defined as Systolic Blood Pressure (SBP) > 220 mm Hg or Diastolic BP > 125 mm Hg. Basically, it was devided into 2 types :

* Hypertensive Urgencies
* Hypertensive Emergencies

Hypertensive Urgency

Hypertensive Urgency are situations in which Blood Pressure must be reduced within a few hours (<> 220 mmHg or DBP > 125 mmHg that persists after a period of observation) and without evidence of acute end-organ damage.

Hypertensive Emergency

Hypertensive Emergency are situations in which SBP > 220 mmHg or DBP > 125 mmHg and require substantial reduction of blood pressure within 1 hour to avoid the risk of serious morbidity or death.

Clinical Manifestation of Hypertensive Emergency :

* Eyes: Retinal hemorrhages and exudates, papilledema.
* CNS: Intracranial hemorrhage, lacunar infarcts, stroke, or hypertensive encephalopathy. The latter is characterized by the insidious onset of headache (often occipital and worse in the morning), nausea, and vomiting, followed by alterations in mental status, lethargy, and restlessness/agitation. Can progress to seizures and coma if untreated. Generally characterized by the lack of localizing neurologic signs.
* CV: Pulmonary edema, unstable angina/myocardial infarction, acute aortic dissection.
* Renal: Malignant nephrosclerosis, leading to acute renal failure, hematuria, and proteinuria. Activation of the renin-angiotensin system can further exacerbate the HTN.
* Hematologic: Hemolytic anemia can occur with severe HTN.

Others Type Of Hypertensive Emergency :

* Malignant Hypertension - In order to diagnose Malignant Hypertension, papilledema must be present
* Accelerated Hypertension - Defined as a recent significant increase over baseline blood pressure that is associated with target organ damage. This is usually vascular damage on funduscopic examination, such as flame-shaped hemorrhages or soft exudates, but without papilledema.

Treatment

Hypertensive Urgency

* Goal : To relieve symptoms and bring BP to reasonable level within 24–48 hours, aiming for gradual attainment of optimal control over several weeks
* Medication : Clonidine, Captopril, Metoprolol, and Hydralazine are effective oral agents.
* Precautions : Avoid B-Blockers if cocaine use, Avoid angiotensin-converting enzyme (ACE) inhibitors if renal artery stenosis suspected, Avoid short-acting dihydropyridine calcium channel blockers because BP reduction is often precipitous

Hypertensive Emergency

* Goal : To reduce mean arterial pressure by 25% in 1–2 h; then to reduce BP to 160/100 mm Hg over next 6–12 h
* Medication : Nitroprusside, labetalol, and nitroglycerin are most commonly used intravenously. Fenoldopam, a peripheral dopamine agonist, is also effective
* Precautions : If with ischemic stroke, only treat if BP exceeds 220/120 mm Hg; aim to reduce by only 10–15%, If thrombolytic agents are to be used to treat ischemic stroke, target BP is <>
* ACE inhibitors are specifically indicated in scleroderma crisis