Is neurosurgery needed for a patient with a subgaleal hematoma, especially in cases of significant trauma, increased intracranial pressure, or severe symptoms such as seizures or altered mental status?

Neurosurgical Management of Subgaleal Hematoma

Most subgaleal hematomas do not require neurosurgery and resolve with conservative management, but urgent neurosurgical intervention is mandatory when the hematoma causes extracranial cerebral compression with elevated intracranial pressure, neurological deterioration, or life-threatening complications. 1

When Neurosurgery IS Required

Neurosurgical evacuation is indicated in the following scenarios:

• Extracranial cerebral compression with radiographic signs of elevated intracranial pressure (overlapping cranial sutures, diffuse cerebral edema, or midline shift) combined with neurological decompensation such as progressive lethargy or posturing movements 1

• Life-threatening brain lesions identified on CT scan that require urgent neurosurgical consultation and intervention after any systemic hemorrhage is controlled 2, 3

• Impending cerebral herniation with altered mental status, requiring emergency neurosurgery with osmotherapy and/or temporary hypocapnia while awaiting surgical intervention 2, 4

• Severe complications including airway compression, orbital compartment syndrome, or periorbital necrotizing fasciitis that threaten vital structures 5, 6

When Conservative Management Is Appropriate

The vast majority of subgaleal hematomas are managed non-operatively:

• Isolated subgaleal hematoma without intracranial pathology, mass effect, or neurological symptoms should be treated conservatively with direct compression using non-elastic bandage packing 7, 8

• Small to moderate hematomas that are not causing compressive symptoms typically resolve spontaneously within 10 days to several weeks without aspiration or drainage 7, 8

• Stable patients without signs of elevated intracranial pressure, hypovolemic shock, or progressive neurological decline can be observed with close monitoring 5, 6

Critical Assessment Algorithm

When evaluating a patient with subgaleal hematoma, follow this sequence:

1. Obtain urgent brain CT scan to rule out underlying intracranial hemorrhage, skull fractures, or mass effect causing brain compression 2, 1

2. Perform neurological evaluation including pupillary examination and Glasgow Coma Scale motor score to identify life-threatening brain damage 2, 4

3. Measure serial head circumferences in cases where the hematoma is expanding, as rapid increases (e.g., 33 cm to 42 cm) indicate massive bleeding requiring intervention 1, 6

4. Monitor for hypovolemic shock with serial hematocrit measurements, as massive subgaleal bleeding can cause exsanguination and disseminated intravascular coagulation requiring blood transfusions 1, 6

5. Assess for compressive complications including airway patency, orbital function, and signs of infection 5, 6

Perioperative Management When Surgery Is Required

If neurosurgical evacuation becomes necessary:

• Maintain systolic blood pressure >100 mmHg or mean arterial pressure >80 mmHg during the procedure 2, 4

• Correct coagulopathy before surgery with platelet count >50,000/mm³ (higher values advisable for neurosurgery) and PT/aPTT <1.5 times normal control 2, 4

• Transfuse red blood cells for hemoglobin <7 g/dL, with higher thresholds for elderly patients or those with cardiovascular disease 2, 4

• Maintain PaO₂ between 60-100 mmHg and PaCO₂ between 35-40 mmHg to optimize cerebral perfusion 2, 4

• Use Jackson-Pratt drainage after evacuation to divert continued bleeding (approximately 200 ml over 2 days in reported cases) 1

Special Considerations

Anticoagulation status is a critical risk factor, as patients on apixaban or other anticoagulants can develop massive subgaleal hematomas from mild head trauma that would otherwise be insignificant 7

Surgical drainage indications in stable patients without intracranial pathology are limited to: severe pain relief, suspected infection, or failure of conservative management after appropriate observation 5, 8

Needle aspiration alone is typically inadequate for massive hematomas and surgical evacuation through a scalp incision is required when intervention is necessary 1, 6

Common Pitfalls to Avoid

• Do not delay neurosurgical consultation when CT shows mass effect or the patient demonstrates neurological deterioration, as extracranial cerebral compression can be fatal 1

• Do not assume all scalp swelling is benign—obtain imaging to differentiate subgaleal hematoma from intracranial pathology or skull fractures 2, 1

• Do not perform surgical drainage for uncomplicated subgaleal hematomas, as most resolve spontaneously and surgery is reserved for specific complications 5, 7, 8

• Avoid hypotension during evaluation and management, as cerebral perfusion pressure must be maintained to prevent secondary brain injury 2, 4