What is the prognosis for a patient with a severe head injury, skull fracture, decorticate posturing, anisocoria, and a Glasgow Coma Scale (GCS) score of 5?

Prognosis for Severe Traumatic Brain Injury with GCS 5, Decorticate Posturing, and Anisocoria

This patient has an extremely poor prognosis with a high likelihood of death or severe disability, with mortality risk exceeding 50-80% and less than 15% chance of achieving functional independence. 1, 2

Critical Prognostic Factors Present

Glasgow Coma Scale Score of 5

• A GCS of 5 (E1, V1, M3) indicates severe traumatic brain injury and is independently associated with poor neurological outcome at 6 months. 1
• The motor component (M3 = decorticate posturing) is particularly concerning, as motor response remains the most robust predictor of severity even when other components are affected. 1
• Historical data shows that patients with initial GCS ≤5 have significantly worse outcomes compared to those with GCS >5, even when other factors are controlled. 3

Rapid Onset Anisocoria

• Anisocoria developing 45 minutes post-injury indicates acute intracranial mass effect, likely from expanding hematoma or severe brain swelling, and is a critical predictor of mortality. 1
• Pupillary size and reactivity are validated as key determinants of neurological outcome at 6 months in large studies including 6,681 and 8,509 patients. 1
• Pupil status is the single most important prognostic factor—mortality approaches 80% when bilateral fixed dilated pupils are present, though this patient currently has anisocoria (unilateral abnormality). 2

Decorticate Posturing

• Decorticate posturing (M3) indicates severe hemispheric injury with intact brainstem function, but represents a critical threshold for poor outcome. 4
• Motor posturing (decerebrate or decorticate) is associated with irreversible brain injury and unfavorable outcomes. 4
• The presence of abnormal motor posturing combined with pupillary abnormalities creates a particularly ominous combination. 1, 2

Age Factor

• At 60 years old, this patient faces additional risk, as age is consistently identified as an independent predictor of poor outcome in severe TBI. 1, 3
• Younger patients (mean age 23-34 years) have significantly better outcomes than older patients even with similar injury severity. 3, 2

Expected Mortality and Functional Outcomes

Mortality Risk

• Overall mortality for GCS 3-5 with pupillary abnormalities ranges from 49-80%. 2
• With unilateral fixed/dilated pupil (anisocoria), mortality is approximately 50-70%. 2
• If pupils progress to bilateral fixed and dilated, mortality increases to nearly 80%. 2

Functional Recovery Potential

• Only 13-25% of patients with GCS ≤5 achieve good functional outcome (Glasgow Outcome Scale 1-2, indicating moderate disability or good recovery) at 6 months. 3, 2
• The majority of survivors remain severely disabled (GOS 3-5), requiring assistance with activities of daily living. 3, 2
• Patients with GCS 5 and abnormal pupils have less than 15% chance of functional independence. 2

Time-Dependent Prognostic Considerations

Critical 72-Hour Window

• Failure to show neurological improvement within 72 hours from injury is a negative prognostic factor associated with poor functional outcome or death. 5
• Serial neurological examinations every 15-30 minutes initially, then hourly, are essential to detect secondary deterioration. 1, 5
• Any decrease of 2 or more points in GCS score should trigger immediate repeat CT imaging. 1

Secondary Insults

• Prevention of secondary brain injury is critical—even brief episodes of hypotension (SBP <90 mmHg) or hypoxemia (SaO2 <90%) dramatically worsen outcomes, with combined insults causing 75% mortality. 1
• Maintain mean arterial pressure ≥80 mmHg and SaO2 >95% to optimize cerebral perfusion. 1, 5

Immediate Management Priorities

Urgent Imaging and Neurosurgical Evaluation

• Immediate non-contrast head CT is mandatory to identify surgical lesions (subdural, epidural, or intraparenchymal hematoma). 1
• Patients with focal brain injuries, especially subdural hematomas, have higher mortality than those with diffuse injuries regardless of GCS. 4
• Neurosurgical consultation is required immediately, as 8-40% of patients with GCS ≤8 require surgical intervention. 1, 6

Intracranial Pressure Monitoring

• ICP monitoring should be strongly considered given the GCS ≤8, skull fracture, and pupillary abnormality. 1
• Elevated ICP that is not reducible indicates unfavorable outcome. 4, 3
• Initial ICP on admission is a significant predictor—patients with lower admission ICP (mean 16 vs 26 mmHg) have better survival. 3, 2

Common Pitfalls to Avoid

• Do not make irreversible treatment limitation decisions before 72 hours unless brain death criteria are met. 5
• Do not delay correction of hypotension and hypoxemia while awaiting imaging or neurosurgical consultation. 1, 5
• Do not assume futility based solely on initial GCS—some patients with GCS 3-5 can achieve functional recovery, particularly younger patients with reactive pupils. 3, 2
• Do not rely on skull fracture presence or absence to predict intracranial injury severity—CT imaging is mandatory. 1, 6

Realistic Family Counseling

Families should be counseled that this injury is life-threatening with greater than 50% mortality risk and that most survivors will have severe permanent disability requiring long-term care. 3, 2 The combination of low GCS (5), abnormal pupils (anisocoria), and abnormal motor response (decorticate posturing) creates a particularly poor prognostic profile. 1, 2 However, aggressive initial management for 72 hours is warranted to identify the subset of patients who may show neurological improvement. 5, 3