The locked-in syndrome consists of almost complete paralysis. Awareness and mental function are not affected. People cannot make facial expressions, move, speak, or communicate on their own, but they can move their eyes up and down and blink.
Locked-in syndrome may result from
Any disorder (almost always a stroke) that destroys the middle part of the brain stem but does not affect the parts of the brain that control consciousness and mental function (the upper part of the brain stem and the cerebrum, the largest part of the brain)
Rarely, complete paralysis of peripheral nerves and muscles, as may result from severe Guillain-Barré syndrome or from cancer that affects the middle part of the brain stem or the area around it
People with locked-in syndrome cannot move their lower face, chew, swallow, speak, move their limbs, or move their eyes from side to side. They may have difficulty breathing but can see and hear. The disorder resembles stupor or coma because people have no obvious way of responding even though they are fully conscious. However, most can move their eyes up and down and blink. If caregivers do not notice the eye movements, people with locked-in syndrome may mistakenly be thought to be unaware of their surroundings and unable to think or communicate. People with this syndrome can learn to communicate by opening and closing their eyes in response to questions.
Whether people recover depends on the cause and its severity, as in the following examples:
If the cause is a small stroke and people are not completely paralyzed, people may recover completely or enough to do some daily tasks, such as eating and speaking, on their own.
If the stroke is large, most people need full-time nursing care permanently.
If the cause is Guillain-Barré syndrome, people may improve over several months, but recovery is seldom complete.
If the cause is a progressive disorder such as cancer, death usually results.
Because this syndrome can be mistaken for stupor or coma, doctors test people who do not move and appear unresponsive by asking them to open and close their eyes.
Imaging tests of the brain, such as magnetic resonance imaging (MRI) and computed tomography (CT), are done to determine the cause, particularly to check for any treatable disorders that may be contributing to the problem. If the diagnosis is in doubt, doctors may do other imaging tests—positron emission tomography (PET), single-photon emission computed tomography (SPECT), or functional MRI.
Early treatment involves correcting any conditions that may contribute to the syndrome. People who have difficulty breathing may need assistance with breathing, such as mechanical ventilation.
Like people in a coma, people in a locked-in syndrome require comprehensive care.
Providing good nutrition (nutritional support) is important. People are fed through a tube inserted through the nose and into the stomach. Sometimes they are fed through a tube (called a percutaneous endoscopic gastrostomy tube, or PEG tube) inserted directly into the stomach through an incision in the abdomen. Drugs may also be given through this tube.
Many problems result from being unable to move, and measures to prevent them are essential (see Problems Due to Bed Rest). For example, the following can happen:
Pressures sores: Lying in one position can cut off the blood supply to some areas of the body, causing skin to break down and pressure sores to form. Caregivers must turn people very frequently.
Contractures: Lack of movement can also lead to permanent stiffening of muscles (contractures) causing joints to become permanently bent.
Blood clots: Lack of movement makes blood clots more likely to form in leg veins.
To prevent these problems, physical therapists gently move the person’s joints in all directions (passive range-of-motion exercises). Therapists may splint joints in certain positions to help prevent contractures. People are also given drugs to prevent blood clots from developing.
Because people are incontinent, care should be taken to keep the skin clean and dry. If the bladder is not functioning and urine is being retained, a tube (catheter) may be placed in the bladder to drain urine.
People with the locked-in syndrome can learn to communicate using a computer input device controlled by eye movements. Other devices can detect when people sniff slightly. These devices can also be connected to a computer and used to communicate. Speech therapists can help people develop a communication code using eye blinks or sniffs. If they recover use of another body part (such as a thumb or the neck), they can communicate in other ways.
However, these methods are tiring and slow. So other methods are being developed using electrodes that are attached to the scalp or implanted in the brain. The electrodes can detect electrical signals produced by nerve cells. These signals are sent to a computer and processed. They can be used to move cursors on a computer screen, operate a robotic arm, and produce computer-generated speech.
Because communication can usually be established, affected people should make their own health care decisions. However, affected people are often very depressed and may need to be advised by a compassionate mental health care practitioner, especially when they are considering future medical interventions and life support measures.
If present, depression is treated.