Cerebral edema - high brain pressure

Cerebral edema occurs when fluid builds up around the brain, which increases brain pressure. The brain pressure is also called intracranial pressure or ICP.

swelling due to fluid that has nowhere to go.
Cerebral edema can have serious consequences.

The brain needs good blood flow to supply oxygen and food, such as glucose. This is necessary in order to function.

 

Cerebral edema can restrict the flow of blood to the brain. As a result, a lack of oxygen in the brain can occur and the brain cells can be damaged or even die. Because the hard skull cannot expand, the brain can be pushed towards the brain stem.

Important parts of the brain stem can become trapped. The brainstem is responsible for respiration, circulation and consciousness.

Cerebral edema can cause irreversible damage and in some cases can be fatal.

 

Complaints

The following complaints can occur

• Headache
• Nausea and vomiting
• Trouble speaking
• Trouble moving
• Trouble seeing
  • double vision
  • blurred vision
• Loss of feeling
• Dizziness
• Pain in the neck
• Epileptic attacks
• Disturbances in consciousness, unconsciousness

 

Treatment

Because increased brain pressure can cause serious damage to the brain and brainstem, medical intervention will be necessary. Possible treatment methods or combinations are listed below.

• Medication depending on the cause:
  • Diuretics, usually corticosteroids, mannitol or glycerol by infusion
  • Anticoagulant medications to dissolve blood clots and help blood to clot less quickly
• Pain relief, because pain can influence the pressure in the brain
• Installing a pressure sensor, a tube with a small pressure sensitive device,  ICP measurement. (This is done in the operating room or ICU and takes about 30 minutes. The tube is attached to the skull with a screw.)
• Keeping the patient asleep / artificial coma
  
• Ventilation
• Surgery
  • Constructing a brain drain / shunt
  • Opening the skull to release the pressure from the brain.
  • Surgery on the damaged brain areas
• Hypothermia / cooling the body

 

Causes of cerebral edema / high brain pressure

 

• Traumatic brain injury

By an accident brain tissue can tear and swell, partly due to blood leakage. The bleeding takes up space within the skull and causes an increase in brain pressure. The walls of the brain capillaries can leak blood plasma, and this plasma then leaks into the brain tissue

- Severe concussion

- Brain contusion

• Cerebral hemorrhage

Cerebral hemorrhage occurs when a blood vessel in the brain ruptures and starts leaking. The bleeding takes up space within the skull and causes an increase in brain pressure.

• Cerebral infarction

Lack of oxygen can damage brain cells and cause swelling and pressure.

• Sinus thrombosis

When a large vein in the brain becomes blocked, the blood cannot be drained, but the arteries supply more blood. Then increased brain pressure can arise.

• Brain abscess
  
• Brain tumor

This can put pressure on other brain areas or prevent brain fluid / liquor from being drained.

• Brain cyst
• High blood pressure pinching surrounding blood vessels
  
• Pregnancy complications
  
• Birth defects
• Hydranencephaly or hydroenencephaly; (partly) missing large brains, causing the skull to fill with fluid
• Hydrocephalus
• Narrowing of the connection between the third and fourth brain chamber

• Disruption in the development of the fourth brain chamber.

• Cerebral hemorrhage in the first days of a baby born prematurely

• Increased production of cerebrospinal fluid

• Inadequate drainage of cerebrospinal fluid with congestion of the brain chambers (ventricles) - ventriculoma

• Disturbance in the balance between production and drainage of cerebrospinal fluid - idiopathic intracranial hypertension - benign intracranial hypertension - pseudotumor cerebri

• Tumor in the organ of production of cerebrospinal fluid (plexus papilloma)
• Enlarged brain chambers, enlarged ventricles after traumatic brain injury (post traumatic ventriculomegaly)
• Normal Pressure Hydrocephalus due to age, resembles dementia. Also called NPH; Normal Pressure Hydrocephalus (see the hydrocephalus page).
  
• Untreated or long-term diabetes that can make the blood vessel wall brittle
• Kawasaki disease; vascular wall inflammation, which causes blood vessels to build up and impedes the drainage of fluid
• Stay at a high altitude above 4000 meters

 

Midline shift

Midline shift literally means the shift of the center line of the brain. It is closely related to intracranial pressure (ICP) explained above.
It describes the situation where the midline of the brain anatomy is no longer centered. The center has moved.
This can occur when the pressure exerted by the pooling of blood and swelling around the damaged brain tissues is so forceful that it pushes the brain away from its center.
It can be a result of traumatic brain injury, stroke, bruising (hematoma) or birth defect in which the brain pressure is increased.

 

There are three brain structures that serve as reference points. If any of these three are misaligned, it indicates that pressure on one side of the brain is pushing the brain out of position.
Being:

1. the septum pellucidum: a thin membrane that runs directly through the center of the brain.
   
2. the third ventricle: a space filled with cerebrospinal fluid located deep in the center of the brain.
   
3. the pineal gland (epiphysis): a small gland located just behind the third ventricle.
   

 

The image below shows a midline shift due to a subdural hematoma

By James Heilman, MD Own work, CC BY-SA 3.0 https://commons.wikimedia.org/w/index.php?curid=16263158

 

Brain pressure facts

• Normal brain pressure / intracranial pressure (ICP) is between 5 and 15 mmHG (mercury pressure), but should remain below 20 mmHg (mercury pressure). ICP should be less than 20 mmHg.
• Another value is cerebral perfusion pressure (CPP), which is also measured to detect and treat cerebral edema. Cerebral perfusion pressure (CPP) is determined by the mean pressure in the arteries (arterial blood pressure, mean arterial pressure (MAP)) and intracranial pressure (ICP) Cerebral perfusion pressure must be between 50 and 70 mmHg.
• The intracranial pressure may also be too low. This is called
  spontaneous intracranial hypotension (SIH) due to a leak in the meninges, allowing cerebrospinal fluid to leak out.

 

Idiopathic Intracranial Hypertension (IIH)

 

Although cerebral edema, high intracranial pressure, and Idiopathic Intracranial Hypertension (IIH) may be related, they are not exactly the same thing.
Cerebral edema refers to swelling in the brain due to a buildup of fluid, often resulting from injury, infection, or other conditions, as discussed on this page. High intracranial pressure refers to the pressure itself that occurs when there is more pressure than normal in the skull, such as due to cerebral edema, a tumor, or a hemorrhage.

Idiopathic Intracranial Hypertension (IIH) is a neurological condition that results from a persistently elevated pressure in the spinal canal.

A change in the pressure regulation in the brain and spinal canal can cause the pressure in thes locations to increase.

This can cause cerebrospinal fluid to press on the nerve roots (compression), which can put pressure on the cranial nerves.

When you go from lying down to standing, the pressure of the cerebrospinal fluid increases in the lower part of your body and it decreases in the upper part.

 

The official name for cerebrospinal fluid is cerebrospinal fluid (CSF). The word 'cerebro' refers to the brain, while 'spinal' refers to the spinal cord. It is also called liquor cerebrospinalis.

The pressure on the nerve roots can cause various symptoms, such as neuropathic pain, tingling, muscle weakness or reduced sensation. This can cause weak spots in the protective layer of the nerves, which can then swell.

 

Idiopathic means: without a clear reason or cause. There are researchers who do think about causes and make connections.

 

One possible cause that is sometimes overlooked is a link to craniocervical instability (CCI). This means that the joints between the skull and the upper cervical vertebrae are not strong enough, which can put pressure on the spinal cord or brainstem. Although not all is clear, studies show that CCI can contribute to changes in cerebrospinal fluid pressure and thus cause or worsen IIH.

 

Pressure on nerve roots in the neck and upper back can cause the following symptoms:

• neuropathic pain
  
• radiating pain in the neck and arms
  
• tingling in the hands, numb hands
  
• tennis elbow
  
• loss of strength in the arms
  
• temperature change in the hands
  
• pain between the ribs
  
• chest pain, often radiating to the front (known as 'Tietze's syndrome')

 

Pressure on the cranial nerves can cause the following symptoms:

• pain when moving the eyes due to painful eye muscles
  
• disrupted control of the eye muscles and therefore double vision
  (cranial nerves III, IV and VI control the eye muscles)
  
• pain in the eyes
  
• tingling or numbness in the face
  
• trigeminal neuralgia, a severe facial pain due to a blood vessel pressing against a nerve in the facial nerve
  
• pain in the jaws, tense jaw muscles
  
• dizziness, vertigo
• altered taste
  
• dry mouth and feeling thirsty
  
• burning pain in the mouth
  
• hoarse voice
  
• difficulty swallowing, risk of choking (dysphagia)
• tinnitus, also known as ringing in the ears
• cognitive symptoms including:
  
  • concentration problems,
    
  • word-finding problems
• chronic fatigue (neurofatigue)
  
• severe headache

 

Read more about the function and symptoms of the 10th cranial nerve Nervus vagus or nX and the optic nerves III, IV and VI.
Information about eye muscles follow this link.