What type of traumatic brain bleed can be drained and what procedure, such as a shunt, is used?

Traumatic Brain Bleeds That Can Be Drained

Epidural hematomas, subdural hematomas, and brain contusions with mass effect are the traumatic brain bleeds that can be surgically drained, but these are evacuated through craniotomy or burr-hole procedures—not shunts. Shunts are used for a different purpose: draining cerebrospinal fluid (CSF) to control intracranial pressure, not for evacuating blood collections. 1

Types of Traumatic Bleeds Requiring Surgical Evacuation

The following traumatic brain bleeds require surgical drainage through direct evacuation procedures 1, 2, 3:

• Symptomatic epidural hematoma (extradural hematoma) at any location requires surgical removal 1, 3
• Acute subdural hematoma with thickness >5mm and midline shift >5mm requires evacuation 1, 3
• Brain contusions with mass effect may require removal after failure of first-line medical management of intracranial hypertension 1, 3
• Closed displaced skull fracture with brain compression (thickness >5mm, mass effect with midline shift >5mm) requires surgical intervention 1

These bleeds are evacuated through craniotomy or burr-hole procedures, not shunts. 1 The blood is directly removed from the subdural, epidural, or intraparenchymal space through surgical access to the skull. 1

When Shunts Are Actually Used in Traumatic Brain Injury

Shunts serve an entirely different purpose in TBI management—they drain CSF, not blood 1:

External Ventricular Drainage (EVD)

• External ventricular drains are placed to control intracranial pressure by draining CSF from the ventricles when medical management fails 1
• This procedure is recommended for persisting intracranial hypertension despite sedation and correction of secondary brain insults 1
• EVD can be inserted using neuronavigation and is effective even when draining small volumes of CSF from normal or small-volume ventricles 1

Acute Hydrocephalus

• Drainage of acute hydrocephalus is a neurosurgical indication in the early phase of severe TBI 1, 3
• This involves placing a drain to remove CSF that has accumulated due to impaired circulation or absorption 1

Critical Distinction: Blood Evacuation vs. CSF Drainage

The fundamental error in thinking about "draining" traumatic brain bleeds with shunts is confusing two separate problems:

1. Blood collections (epidural, subdural, intraparenchymal hematomas) require direct surgical evacuation through craniotomy or burr-holes 1, 3

2. Elevated intracranial pressure from CSF accumulation requires ventricular drainage or shunting 1

Important Caveat About Shunts and Subdural Hematomas

Pre-existing CSF shunts actually increase the risk of subdural hematoma after trauma. 4, 5, 6 Patients with hydrocephalus who have CSF shunts are predisposed to developing subdural hematomas, especially after even minor head trauma. 4, 6 In these cases, management often requires shunt ligation or pressure adjustment rather than using the shunt to drain the hematoma. 4

Decompressive Craniectomy for Refractory Cases

When intracranial pressure remains elevated despite medical management and CSF drainage, decompressive craniectomy is recommended in multidisciplinary discussion at the early phase of TBI. 1, 2 This involves removing a portion of the skull to allow the swollen brain to expand, rather than draining fluid through a shunt. 1

Prognostic Considerations

Large bleeds have substantially worse outcomes than small bleeds. 7 The odds ratios for mortality comparing large versus small bleeds are: subdural hematoma 3.41, intraparenchymal hemorrhage 3.47, and epidural hematoma 2.86. 7 This underscores the importance of prompt surgical evacuation when indicated rather than attempting conservative management or inappropriate drainage procedures. 7