Locked-In Syndrome

What Is Locked-In Syndrome?

Locked-in syndrome is a rare neurological condition characterized by quadriplegia and the ability to communicate only with eye movements while the individual is in a conscious state. The most common cause of locked-in syndrome is damage to the pons, which is part of the brain. This usually happens when the pons does not receive enough blood.

Symptoms and Signs

Locked-in syndrome has signs and symptoms that are evident upon close examination. These signs and symptoms include:

• Quadriplegia: A paralysis of voluntary muscles in all four limbs and the torso. There is no ability to voluntarily move below the neck, speak, show facial expression, chew, swallow, or breathe normally.
• Conscious status: A person with locked-in syndrome is awake and has intact cognitive function. They can hear, see, and respond with certain eye and eyelid movements. These eye movements are very important as a means of communication.
• Prevalence: Locked-in syndrome happens to men and women in equal numbers; it can happen at any age, but it is more common in adults.
• Variants: Locked-in syndrome can have subtle differences from person to person, but in this state, individuals are totally dependent on caregivers.

The signs and symptoms of locked-in syndrome are specific to the condition and must be present for a healthcare provider to make an accurate diagnosis.

Classification Of Locked-In Syndrome

Locked-in syndrome has three main types, and each has been designated with the following names:

• The classic form: There are no voluntary muscle movements except for the eyes and eyelids, allowing for blinking and movement of the eyes up and down. Your loved one cannot speak but can see, hear, and understand spoken statements. The individual is locked in a paralyzed body.
• The incomplete form: The incomplete form of locked-in syndrome is similar to the classic type, except there is some voluntary movement and sensation. It may also be a stage of the syndrome where some recovery is taking place.
• The complete or total form: With complete locked-in syndrome, there is total paralysis with no voluntary movement and no eye movement. They are unable to communicate or express their needs.

For proper diagnosis, a healthcare professional will carefully evaluate the patient using appropriate testing, which will usually disclose the type of locked-in syndrome the individual has.

Locked-In Syndrome Causes

The most common cause of locked-in syndrome is an injury to the pons, a part of the brainstem. The most prevalent causes of locked-in syndrome are:

• Damage to the pons: An interruption of blood circulation to the pons can happen from an infarction or hemorrhage. Damage to the pons also can happen from traumatic brain injuries, stroke, tumors, toxins, cocaine abuse, loss of myelin—which protects the nerves in this area—inflammation, and disorders like multiple sclerosis and amyotrophic lateral sclerosis.
• Medical negligence: Medical errors can happen if the provider fails to address high-risk conditions, misdiagnoses brainstem strokes, or makes a mistake with anesthesia, or when a patient has an adverse reaction to medicines or complications develop during surgery. These incidents may be found if the medical records are examined by someone with medical knowledge.
• Damage to other parts of the brain: Injury to the cortical areas and white matter fiber tracts can also cause locked-in syndrome.

Although strokes in the pons region are usually the cause of locked-in syndrome, other causes are possible and should be ruled out before a definitive diagnosis is made.

Medical Negligence

Medical negligence may cause locked-in syndrome in a variety of ways, including:

• If the correct diagnosis is not ascertained
• If high-risk conditions are not addressed
• If there is an adverse reaction to a medication
• If an error is made during anesthesia
• If complications during surgery are not correctly treated

If a family suspects medical negligence caused locked-in syndrome, they should secure all medical records, document events, consult a medical malpractice attorney, and consider an independent expert review. Meanwhile, ensure the patient receives proper care and seek support for family and caregivers.

A careful and thorough evaluation must be made to correctly diagnose and treat locked-in syndrome.

How Does A Provider Diagnose Locked-In Syndrome?

To make an accurate diagnosis of locked-in syndrome, a full medical history from the patient’s family or friends is essential. The provider will evaluate this history and conduct a thorough physical exam. The provider may also order various tests to determine an accurate diagnosis and to eliminate other conditions.

A thorough history may demonstrate risk factors for a stroke, such as high cholesterol, hypertension, or a family history of strokes.

To diagnose a patient with locked-in syndrome, the provider will look for symptoms like quadriplegia and an inability to speak while still having eye and eyelid movements. Tests such as an MRI of the brain, a cerebral angiogram, an EEG, blood tests, and examination of the cerebrospinal fluid may help the provider make an accurate diagnosis and rule out other conditions.

What Disorders Mimic Locked-in Syndrome?

The diagnosis of locked-in syndrome may be overlooked due to the difficulty of evaluating the patient, as speech is not possible. When your loved one can only move their eyes and cannot speak, important information may be initially missed because the first aim of providers is to stabilize the patient. If a healthcare professional is unaware of the ability to communicate through eye movements, an accurate diagnosis may not be made initially. Conditions that may mimic locked-in syndrome are:

• Unresponsive wakefulness syndrome: Individuals cannot follow verbal commands with their eyes and lack awareness of themselves and their environment.
• Minimally conscious state: In a minimally conscious state, individuals show inconsistent awareness of themselves and their surroundings.
• Akinetic mutism: Individuals are awake and alert but cannot or will not initiate communication with their eyes.

Locked-In Syndrome Treatment

There is no specific cure for locked-in syndrome, but the underlying cause of the condition should be addressed. If the patient has a blood clot causing an interruption of blood flow to the pons, the provider may want to dissolve the clot if not too much time has passed since the injury occurred. Similarly, if a tumor has caused the locked-in syndrome, a provider may want to treat the tumor.

Supportive care is extremely important for locked-in syndrome since the patient cannot chew and will have difficulty breathing. Usually, a feeding tube is needed for nutrition, and a tracheotomy and breathing assistance are required to aid respiration. These measures will help prevent aspiration pneumonia and respiratory failure.

A person with locked-in syndrome will also require physical therapy to prevent limb contractions, and the patient should be turned on a regular basis on a special mattress in an attempt to prevent bedsores.

It is important for the provider to assist with communication, and this usually starts with eye contact. The provider will attempt to determine which type of eye movement is easiest for the patient. Blinking once can represent yes, and blinking twice can represent no. Looking up or down can have various meanings, as can closing the eyes. A speech therapist can point to individual letters on a sheet, and the patient can signal appropriately to spell words.

Eventually, the provider may introduce electronic communication machines and infrared eye tracking devices to allow the use of a computer with an artificial voice.

Outlook For Individuals With Locked-In Syndrome And Their Caregivers

If you are caring for someone with locked-in syndrome, it is imperative to advocate for the individual as much as possible. With appropriate support and care, people with locked-in syndrome can maintain comfort, dignity, and the best possible quality of life.