Traumatic Brain Injury (TBI)

Traumatic Brain Injury (TBI)

• TBI is typically caused by a sudden and violent blow or jolt to the head.
• Closed injuries involve a blow or jolt without penetration.
• Open injuries involve penetration of an object through the head.
• TBIs disrupt normal brain function.
• Injuries can cause bruising, nerve fiber damage, and hemorrhaging.
• Focal injuries are localized to one spot, while diffuse injuries affect the whole brain.
• Diffuse axonal injury involves the shearing of neurons and is often widespread, potentially leading to permanent brain damage.
• TBI severity ranges from mild to severe, with severe cases potentially leading to a vegetative state.
• High-risk groups include: males, children aged 0-4, adolescents aged 15-19, adults over 75, military personnel (e.g., paratroopers), and African-Americans (highest death rate).

TBI Complications

• Complications can result from a single significant event or multiple mild events.
• Mild complications can progress to severe, including death
• Complications include changes in thinking, sensation, language, or emotions, seizures, Alzheimer's, Parkinson's, memory decline, and depression.
• Falls are a significant cause of TBI followed by traffic accidents
• Being struck on the head is another cause of TBI

Concussion

• Concussion is a momentary interruption of brain function, with approximately three million cases annually
• Concussions are caused by a violent jarring or shaking resulting in a disturbance of brain function and can sheare axons
• The brain slams against the skull due to a blow to the head, disrupting neurological functioning
• Loss of consciousness may or may not occur, but longer unconsciousness indicates a more serious concussion
• Amnesia is an indicator of increased severity
• Other symptoms include confusion, sleep disturbances, and headaches, with neurological complaints being common
• Early signs include headache, nausea, and vomiting, and more symptoms indicate greater severity
• There is no cure, treatment includes rest and restricting activities, especially screens and excessive socializing
• Medications can be used for headaches and nausea
• The brain is more sensitive to further damage after a concussion

Cerebral Contusions

• Cerebral contusions involve bruising of brain tissue leading to bleeding
• Contusions typically result from blunt blows, causing the brain to impact the skull
• Coup is the initial area of impact, while countercoup is the area on the opposite side of the brain where it rebounds.
• Severity depends on the extent of damage and bleeding, with residual effects depending on severity

Fractures

• Fractures can be either open or closed
• Closed injuries can result from direct or rebound impacts
• Open injuries involve bone fragments penetrating the brain
• Manifestations: May be vague, develop slowly, or be sudden and severe. Can improve or worsen suddenly
• Symptoms are not indicated severity
• Concussion indications include headaches, nausea, vomiting, and amnesia
• Fluid draining from the nose, ears, or mouth suggests a skull fracture with cerebral spinal fluid leakage
• Other signs include skull or face fractures, facial bruising, swelling, and potential cranial nerve involvement affecting hearing, smell, taste, speech, or vision.
• Irritability, especially in children, can indicate brain swelling.
• Changes in personality and unusual behavior may occur due to frontal lobe involvement
• Serious signs include loss of consciousness, decreased respiratory rate, and hypotension indicating brain stem involvement
• Other symptoms include restlessness, lack of coordination, lethargy, stiff neck, and vomiting.
• Diagnosis involves history, physical exam, Glasgow Coma Scale, and CT/MRI scans
• Treatment: Rest, analgesics (acetaminophen), cold compresses, diuretics, anti-seizure meds, sedatives (with caution), surgery for depressed fractures, and therapy as needed
• Preventative measures include wearing seatbelts, using safety seats, making homes safe, storing firearms securely, not driving impaired, and supervising children

Secondary Brain Injury

• Secondary brain injury is injury caused after admission, as a complication
• The goal for TBI is to prevent secondary brain injury.
• Patients with head injuries lose their ability to auto-regulate blood pressure, making them vulnerable to hypotension and hypoxia
• Secondary injuries include: epilepsy, infections, blood clots/bleeds, brain swelling, increased intercranial pressure, hypoxia, hypotension, acidosis, changes in sodium levels, changes in blood sugar, changes in temperature.
• Treatment focuses on rapid intervention to prevent these complications

Hematomas

• Hematomas are a collection of blood in the tissue that develops from ruptured blood vessels after a TBI or surgery
• Common causes include head injuries and anticoagulant use (Warfarin)
• Types of hematomas include: epidural (above the dura), subdural (below the dura), and intracerebral (inside the brain tissue)
• Mnemonic PAD Mo to remember skull layers: Pia, Arachnoid, Dura mater

Epidural Hematoma

• Epidural hematomas develop between the dura and the skull.
• Typically caused by arterial tears, particularly in the middle meningeal artery (arterial bleed).
• Develops within hours of injury.
• The typical symptom pattern is a brief loss of consciousness, followed by a short period of alertness (lucid interval), then rapid decline in consciousness.

Subdural Hematoma

• Subdural hematomas develop between the dura and the arachnoid.
• Frequently caused by small venous tears.
• Develops slowly
• Acute subdural hematoma manifests within 24 hours of injury and progresses rapidly with a high mortality rate.
• Chronic subdural hematomas are a slow leak over several weeks, more common in older adults with brain atrophy

Intracerebral Hematoma

• Intracerebral hematomas result from bleeding within the brain tissue
• Caused by contusions, shearing injuries, hypertension, strokes, and aneurysms
• Bleeding leads to localized pressure on nearby tissue, increasing intercranial pressure (ICP)
• First signs of ICP are headaches
• Bleeding can trigger vasospasms, worsening ischema and potentially leading to stroke
• Vasospasms can lead to death and disability
• Vasodilators utilized to prevent vasospasms
• Increased intracranial pressure can result in herniation.
• Diagnosis involves history, physical examination, Glasgow Coma Scale, CT scan, MRI, and angiogram.
• Treatment may involve no intervention, blood removal, surgical intervention.
• Strategies include respiratory management, seizure precautions, and temperature regulation.

Subarachnoid Hemorrhage

• Subarachnoid hemorrhage results from bleeding in the space between the arachnoid and pia mater.
• Primary clinical presentation is a severe headache with sudden onset.
• Pain is worse near the back of the head due to the depth of the bleed within the skull
• Common cause is the rupture of an aneurysm within the subarachnoid space.