From the Guidelines
For elevated intracranial pressure, mannitol infusion is recommended at a bolus dose of 0.5-1g/kg, which can be repeated once or twice as needed, provided serum osmolality has not exceeded 320 mosm/L. This recommendation is based on the findings of a study published in Hepatology in 2005 1, which suggests that mannitol is effective in decreasing cerebral edema in patients with acute liver failure.
Key Considerations
- The dose of mannitol should be administered intravenously, with careful monitoring of serum osmolality to avoid exceeding 320 mosm/L.
- Patients with renal impairment are at risk of volume overload and may require dialysis to remove excess fluid.
- Hyperosmolarity or hypernatremia may result from overzealous use of mannitol, emphasizing the need for careful monitoring.
- Prophylactic administration of mannitol is not indicated, and its use should be reserved for treating episodes of elevated intracranial pressure.
Administration and Monitoring
- Mannitol should be administered through a filter to remove any crystals that may have formed.
- Patients should have a urinary catheter in place to monitor output, as mannitol is an osmotic diuretic that will increase urine production.
- Blood pressure, electrolytes (particularly sodium), and renal function should be closely monitored during treatment, as per standard clinical practice 1.
From the FDA Drug Label
Reduction of Intracranial Pressure and Brain Mass: Adults: 0. 25 to 2 g/kg body weight as a 15% to 25% solution administered over a period of 30 to 60 minutes Pediatric patients: 1 to 2 g/kg body weight or 30 to 60 g/m2 body surface area over a period of 30 to 60 minutes. Small or debilitated patients: 500 mg/kg
The recommended dosage and administration of mannitol infusion for elevated intracranial pressure is:
- Adults: 0.25 to 2 g/kg body weight as a 15% to 25% solution administered over 30 to 60 minutes
- Pediatric patients: 1 to 2 g/kg body weight or 30 to 60 g/m2 body surface area over 30 to 60 minutes
- Small or debilitated patients: 500 mg/kg 2
From the Research
Mannitol Infusion for Elevated Intracranial Pressure
- The recommended dosage and administration of mannitol infusion for elevated intracranial pressure are not explicitly stated in the provided studies, but the effects of mannitol compared to hypertonic saline are discussed 3, 4, 5, 6, 7.
Comparison with Hypertonic Saline
- Studies have compared the effects of mannitol and hypertonic saline in the treatment of elevated intracranial pressure in traumatic brain injury, with some indicating that hypertonic saline may have lower treatment failure and lower intracranial pressure 30-60 minutes after infusion termination compared to mannitol 3.
- Another study found that equimolar doses of 20% mannitol solution and 7.45% hypertonic saline solution had similar effects on reducing intracranial pressure, but mannitol caused a significantly greater increase in urine output 4.
- A meta-analysis found that hypertonic saline was more effective than mannitol in intracranial pressure management, but the results did not lend a specific recommendation to select one over the other as a first-line treatment 5.
Administration and Dosage
- One study used a single equimolar infusion of 255 mOsm dose of either 231 mL of 20% mannitol or 100 mL of 7.45% hypertonic saline during 20 minutes of administration 4.
- Another study used a bolus dose of an intracranial pressure-lowering agent, but the specific dosage and administration of mannitol were not reported 6.
Clinical Considerations
- Pretreatment factors, such as serum sodium, systemic hemodynamics, and brain hemodynamics, should be considered when choosing between mannitol and hypertonic saline for patients with increased intracranial pressure 4, 6.
- The choice of treatment may depend on the specific clinical scenario and the patient's individual needs, and further studies are required to validate the findings and provide more definitive conclusions 3, 5, 7.