Is mannitol given in Epidural Hematoma (EDH)?

Mannitol Use in Epidural Hematoma (EDH)

Yes, mannitol is indicated for EDH patients who show signs of threatened intracranial hypertension or brain herniation, but it should NOT be given prophylactically to patients without these clinical signs. 1

When to Administer Mannitol in EDH

Mannitol is specifically recommended in the following clinical scenarios:

• Clinical signs of herniation including mydriasis, anisocoria, or acute neurological deterioration 1
• Threatened intracranial hypertension after controlling secondary brain insults 1
• Directly measured ICP >20 mmHg in patients with ICP monitoring 1
• As a temporizing measure before definitive surgical evacuation 1

High-Risk EDH Features Requiring Aggressive Management

Certain patient characteristics warrant heightened vigilance and readiness for mannitol administration:

• Preoperative Glasgow Coma Scale motor response ≤5 1
• Anisocoria present on examination 1
• Hematoma volume >25 mL 1

Dosing Protocol

Initial dose: 0.25-0.5 g/kg IV (approximately 250 mOsm of 20% mannitol) infused over 15-20 minutes 1, 2

Repeat dosing: Every 6 hours as needed 1, 3

Maximum daily dose: 2 g/kg 3, 2

The FDA label confirms these dosing parameters, specifying 0.25 to 2 g/kg body weight as a 15% to 25% solution over 30 to 60 minutes for reduction of intracranial pressure 2

Critical Monitoring Requirements

• Serum osmolality must be monitored continuously and mannitol discontinued when it exceeds 320 mOsm/L to prevent renal failure 1, 4
• Effective ICP reduction correlates with serum osmolality increases ≥10 mOsm 1
• Onset of action occurs within 10-15 minutes, with effects lasting 2-4 hours 3

Absolute Contraindications

Do NOT administer mannitol in EDH patients with:

• Serum osmolality >320 mOsm/L 4, 2
• Well-established anuria due to severe renal disease 2
• Severe pulmonary congestion or frank pulmonary edema 2
• Active intracranial bleeding except during craniotomy 2
• Severe dehydration 2
• Severe hypovolemia or hypotension 4

Postoperative Considerations

This is critically important: 50-70% of EDH patients develop postoperative intracranial hypertension after hematoma evacuation, with over 40% experiencing uncontrollable intracranial hypertension 1. Therefore:

• Maintain readiness for mannitol administration in the immediate postoperative period 1
• Monitor for secondary bleeding, new extra-axial collections, or increased brain edema as causes of ICP elevation 1

Adjunctive Measures

Mannitol should be used in conjunction with:

• Head-of-bed elevation 20-30 degrees 1
• Neutral neck position 1
• Sedation and analgesia 1
• Brief hyperventilation if needed 1

Alternative Agent

Hypertonic saline (3% or 23.4%) is an effective alternative when mannitol is contraindicated, with comparable ICP-lowering efficacy at equiosmolar doses (approximately 250 mOsm) 1, 4. Hypertonic saline is preferable when hypovolemia or hypotension is a concern, as it has minimal diuretic effect and can increase blood pressure 4

Key Clinical Caveat

Do NOT use mannitol prophylactically in EDH patients without clinical evidence of elevated ICP or impending herniation 4. Prophylactic administration is not recommended and may lead to complications including the need for larger doses later if ICP does rise 5. The decision to use mannitol must be based on objective clinical findings or measured ICP values, not on the mere presence of EDH alone.