From the Guidelines
Mannitol is not recommended for the treatment of hypertensive crisis or elevated blood pressure. The most recent and highest quality study, 1, published in the European Heart Journal in 2019, provides guidance on the management of hypertensive emergencies, emphasizing the importance of controlled blood pressure reduction to safer levels without risk of hypotension. This study suggests that patients with hypertensive emergencies should be treated with intravenous medications such as labetalol or nicardipine in a clinical setting with close hemodynamic monitoring.
Key Considerations
- Mannitol is an osmotic diuretic primarily used to reduce intracranial pressure in conditions like cerebral edema, acute angle-closure glaucoma, or to promote diuresis in cases of drug toxicity.
- For hypertensive emergencies, first-line medications include intravenous labetalol (10-20 mg IV bolus, followed by 20-80 mg every 10 minutes as needed, or 0.5-2 mg/min infusion), nicardipine (5 mg/hr IV, titrated by 2.5 mg/hr every 5-15 minutes, maximum 15 mg/hr), or clevidipine (1-2 mg/hr IV, doubled every 90 seconds until near target BP, maximum 32 mg/hr).
- For hypertensive urgencies, oral medications like captopril (25 mg), labetalol (200-400 mg), or amlodipine (5-10 mg) are appropriate.
- Mannitol has limited effect on blood pressure and may temporarily increase blood volume before diuresis occurs, potentially worsening hypertension, as noted in studies such as 1 and 1.
- Additionally, mannitol can cause significant fluid and electrolyte disturbances, making it unsuitable for blood pressure management.
Treatment Focus
The treatment of hypertensive crisis should focus on medications that directly affect vascular tone or cardiac output rather than osmotic diuretics. This approach is supported by the most recent guidelines and studies, including 1, which emphasize the importance of controlled blood pressure reduction and the use of specific medications for hypertensive emergencies.
From the Research
Mannitol in Hypertensive Tension
- Mannitol is not typically used as a primary treatment for hypertensive tension, but rather for intracranial hypertension 2, 3.
- Studies have compared the effectiveness of mannitol and hypertonic saline in reducing intracranial pressure, with some suggesting that hypertonic saline may be more effective 2, 3.
- However, there is insufficient evidence to support a formal recommendation on the use of any specific hyperosmolar medication in patients with acute increased intracranial pressure 2.
- In the context of hypertensive emergencies, intravenous antihypertensive agents such as nicardipine, nitroprusside, and labetalol are recommended, but mannitol is not typically used for this purpose 4.
- Diuretics, such as thiazide diuretics, are sometimes used to treat hypertension, but mannitol is not a diuretic and is not typically used for this purpose 5, 6.