Epidural Hematoma

Overview  

An epidural hematoma (EDH) is a medical condition characterized by the accumulation of blood between the protective skull and the outermost layer of the brain, known as the dura mater. The dura mater serves as a crucial protective barrier for the brain, but when there is a rupture in a blood vessel, typically an artery, it can lead to the leakage of blood into this space, forming a pocket that exerts pressure on the brain. This condition often arises from head injuries and is occasionally categorized as a type of traumatic brain injury (TBI). It is also known by various names such as extradural hematoma, epidural hemorrhage, or intracranial hematoma. 

Typically, the classic symptoms associated with EDH involve a brief loss of consciousness followed by a period of alertness that may extend for several hours before a decline in brain function occurs, sometimes resulting in the patient entering a coma. EDH is a critical medical emergency that necessitates immediate medical attention and treatment. 

Symptoms  

Epidural hematoma (EDH) is a traumatic brain injury characterized by a distinct symptom progression in some cases. Following a head trauma, individuals with EDH typically experience the following stages: 

• Initial loss of consciousness: Immediately after the head injury, there is a brief episode of unconsciousness. 
• Period of alertness: Subsequently, a period of apparent alertness ensues, lasting several hours in some instances. 
• Deterioration: However, this interval of alertness may be followed by a deterioration in consciousness and a decline in brain function. It is important to note that this deterioration does not invariably lead to a coma but may do so in certain cases.

Additional signs and symptoms of EDH may manifest minutes to hours after the head injury, including: 

• Severe headache: The individual experiences an intense and often incapacitating headache. 
• Nausea and vomiting: They may feel nauseated and may vomit. 
• An enlarged pupil in one eye: One eye may exhibit an enlarged pupil (anisocoria) in comparison to the other. 
• Confusion: A state of mental confusion and disorientation may become evident. 
• Slurred speech: Speech may become incoherent and difficult to understand. 
• Dizziness: Feelings of dizziness or vertigo may be reported. 
• Hemiparesis: Weakness affecting one side of the body may become apparent, leading to difficulty in movement and coordination. 

If left untreated with persistent bleeding, the situation can lead to elevated intracranial pressure, exacerbating symptoms such as seizures, respiratory difficulties, cognitive impairment, eventual coma, and ultimately, fatal outcomes. 

Causes   

An epidural hematoma (EDH) typically results from a head injury, with a skull fracture occurring in approximately 75% of cases. The primary source of bleeding in most cases is a torn middle meningeal artery. However, in some instances, an EDH can develop due to bleeding from a vein. 

In addition to trauma–related causes, EDH can also occur due to non–traumatic factors, including: 

• Infection or abscess. 
• Coagulopathy, where your blood does not clot properly. 
• Hemorrhagic tumors, which are tumors that lead to bleeding. 
• Vascular malformations, such as arteriovenous malformations and cavernous malformations. 

The primary cause of spinal epidural hematomas is often spontaneous bleeding from veins, which can be triggered by coagulopathies or the use of anticoagulant medications. Other contributing factors and causes include: 

• Bone fractures in the vertebrae. 
• Medical procedures like lumbar punctures or epidural anesthesia. 
• Presence of spinal arteriovenous malformations or other vascular abnormalities. 
• Spinal tumors. 
• Pregnancy. 

Risks factors  

Epidural hematomas (EDH) can develop in individuals who sustain head injuries, but they are more frequently observed in younger individuals, particularly those with skull fractures. Common causes of head injuries include sports activities like snowboarding, skateboarding, and biking, as well as automobile or motorcycle accidents. EDHs are four times more prevalent in males than females and are uncommon both in children under two years old and adults over 60 years old.