Overview of Elevated Intracranial Pressure

Understanding Elevated Intracranial Pressure (ICP)

Elevated intracranial pressure (ICP) occurs when the pressure inside the skull rises to a dangerous level, potentially causing brain damage or even death. This pressure can result from conditions such as traumatic brain injury, bleeding in the brain, tumors, or infections. Common signs include persistent headaches, nausea, vomiting, and visual disturbances—especially when lying down.

What Is Intracranial Pressure?

Intracranial pressure refers to the force exerted by the brain tissues, cerebrospinal fluid (CSF), and blood within the skull. These three components must remain in balance for normal brain function. If any one of them expands or is disrupted, pressure within the skull increases.

Normal ICP ranges from 5 to 15 mmHg. When levels exceed 20 mmHg, it may start to damage brain structures. The body initially tries to compensate by shifting CSF or reducing blood volume, but once those mechanisms fail, pressure builds rapidly.

Symptoms of Elevated Intracranial Pressure

One of the earliest indicators of increased ICP is a worsening headache that intensifies when lying flat and eases when sitting or standing. This happens because gravity affects fluid distribution in the brain.

Other common symptoms include:

• Nausea and vomiting

• Behavioral changes

• Seizures

• Blurred or double vision

• Sensitivity to light

• Difficulty concentrating

In infants, signs may include:

• Bulging soft spot (fontanelle)

• Widened sutures (skull gaps)

• Irritability and poor feeding

Visual Disturbances Linked to ICP

The optic nerves are especially sensitive to elevated pressure, and swelling—known as papilledema—can occur. This condition can result in:

• Temporary vision loss or blurring

• Narrowed visual field

• Permanent vision damage if untreated

Papilledema often presents alongside headaches and nausea.

How Elevated ICP Harms the Brain

As pressure rises, brain tissue can shift or become compressed. For instance, if one hemisphere swells due to bleeding or a mass, it can be pushed across the brain’s internal divisions, damaging healthy areas.

A severe example is herniation, where the brain is forced through small openings such as the one near the brainstem, leading to irreversible injury, paralysis, coma, or death.

Common Causes of Increased Intracranial Pressure

Several conditions can contribute to rising ICP:

• Head trauma

• Brain tumors (benign or malignant)

• Brain bleeds (intracerebral or subarachnoid hemorrhage)

• Ischemic strokes

• Hydrocephalus (fluid buildup)

• Infections like meningitis or encephalitis

Sometimes, the cause is unknown. In such cases, it’s called Idiopathic Intracranial Hypertension (IIH).

Diagnosing Elevated Intracranial Pressure

Diagnosis often begins with a physical and neurological exam. A fundoscopic eye exam may reveal optic nerve swelling.

In more severe cases, an intracranial pressure monitor is surgically inserted through the skull to provide real-time readings. This might involve:

• Intraventricular catheter (within CSF space)

• Subdural bolt (beneath brain membrane)

• Epidural sensor (outside the membrane)

A lumbar puncture (spinal tap) may also be used to measure pressure, though it can be risky if ICP is extremely high.

Treating Elevated Intracranial Pressure

Management depends on severity. Mild increases might respond to simple interventions such as:

• Elevating the head

• Avoiding activities that raise pressure

• Administering medications like acetazolamide to reduce CSF production

In moderate to severe cases, treatment may include:

• Mannitol or hypertonic saline to draw fluid away from the brain

• Steroids to reduce inflammation

• Hypothermia therapy to lower body temperature and swelling

• Craniectomy (surgical removal of part of the skull) to relieve pressure

Sedatives like propofol may also be used to slow brain metabolism and protect brain function.

A Word From the Medical Community

Early recognition of elevated intracranial pressure is essential for preventing long-term neurological complications. Symptoms can vary depending on the patient’s age and underlying cause, so timely medical intervention is critical.