What is the treatment for Diffuse Axonal Injury (DAN)?

Treatment for Diffuse Axonal Injury (DAI)

There is no specific treatment for the primary axonal damage in diffuse axonal injury; management focuses entirely on preventing secondary brain injury through aggressive physiological optimization and early rehabilitation. 1, 2

Acute Physiological Management

The cornerstone of DAI management is preventing secondary brain injury through meticulous control of cerebral perfusion and oxygenation:

Blood Pressure Management

• Maintain systolic blood pressure >110 mmHg at all times to ensure adequate cerebral perfusion. 1
• This threshold is critical as DAI patients are particularly vulnerable to hypotension-induced secondary ischemic injury.

Ventilation Control

• Perform tracheal intubation and mechanical ventilation with continuous end-tidal CO2 monitoring. 1
• Avoid hypocapnia, which causes cerebral vasoconstriction and increases the risk of brain ischemia. 1
• This is a common pitfall—overzealous hyperventilation can worsen outcomes despite appearing to "protect" the brain.

Intracranial Pressure Monitoring

• ICP monitoring is recommended for patients with severe traumatic brain injury to detect intracranial hypertension. 1
• Intervene when ICP exceeds 20 mmHg. 1

Diagnostic Imaging Strategy

While not "treatment" per se, proper imaging guides management decisions:

• Non-contrast CT is mandatory first-line imaging and should be performed without delay. 1, 2
• CT has significant limitations in detecting DAI, as microhemorrhages may not be visible. 2
• MRI is indicated when CT results are normal but persistent unexplained neurologic findings are present. 1, 2
• Optimal MRI sequences include T2*-weighted gradient-echo imaging, susceptibility-weighted imaging (SWI), and diffusion-weighted imaging (DWI). 1, 2
• Gadolinium-based contrast agents are not necessary for conventional MRI in traumatic brain injury. 2

Rehabilitation and Long-Term Management

Early physical therapy and rehabilitation are essential to prevent joint contractures and muscle atrophy. 1

Specific Interventions

• Proper positioning and frequent repositioning to prevent pressure injuries and contractures. 1
• Range of motion exercises initiated as soon as medically stable. 1
• Splinting to maintain functional joint positions. 1
• Task-oriented approaches and bowel-bladder retraining exercises as consciousness improves. 3, 4

Monitoring Strategy

• Regular neurological assessments are necessary to detect clinical deterioration. 1
• Follow-up imaging is indicated only with neurological deterioration, not on a routine basis. 1
• This avoids unnecessary radiation exposure and cost while ensuring timely detection of complications.

Multidisciplinary Approach

Regular multidisciplinary case reviews are recommended for patients with severe DAI. 1, 2

Key Considerations

• Early communication with regional neuroscience centers is essential for patients with perceived devastating brain injury. 1
• Establish patient values and preferences early to guide end-of-life care planning if needed. 1
• Honest and realistic discussions of the most likely outcome should occur at admission. 1
• The location and extent of DAI lesions correlate with clinical outcomes, with DAI Stage 3 (dorsolateral brain stem lesions) associated with poor outcomes. 2

Common Pitfalls to Avoid

• Do not rely on CT alone to rule out DAI—it misses most cases of axonal injury. 2
• Avoid hyperventilation—hypocapnia worsens cerebral ischemia despite lowering ICP. 1
• Do not delay rehabilitation—early mobilization prevents contractures that significantly impair long-term functional independence. 1, 3, 4
• The number of microhemorrhages on MRI, while helpful for diagnosis, is not associated with injury severity or outcomes. 2

Prognostic Factors

Understanding prognosis helps guide realistic goal-setting:

• The presence of both a contusion and >4 foci of hemorrhagic axonal injury on MRI is an independent prognostic predictor. 2
• Early subacute MRI findings improve prediction of 3-month outcomes. 2
• Consistency in performing physiotherapy exercises aids in achieving maximum functional independence and improves quality of life. 3, 4