Artificial coma

definition

Artificial coma is a term used for long-term general anesthesia. As with short-term general anesthesia during an operation, an artificial coma consists of several aspects. The sensation of pain, consciousness and muscle work with medication are switched off. This is often a way to give the body time to recover from major surgeries and injuries. The circulation and the functioning of the brain are monitored and protected and the energy and oxygen requirements are reduced. The stress that the body experiences in life-threatening illnesses and injuries is also reduced, which increases the chances of recovery.

Causes & application

An artificial coma, i.e. maintaining anesthesia, is used for life-threatening illnesses and injuries. The diseases include, for example, threatening blood poisoning with so-called septic shock. The body is often severely weakened by bacteria in the blood and must be treated with antibiotic therapy. The artificial coma prevents an excessive stress reaction of the body, which could otherwise endanger the person affected.

Another example of an artificial coma cause is major surgery. After brain or heart operations, an artificial coma is often induced in order to protect the body and to have more precise control over the health of the person concerned.

Another reason to induce an artificial coma is serious injury, especially if the brain is affected.It can prevent involuntary movements, which impair healing, and by buffering the inflammatory reaction, a possible pressure development in the brain can be alleviated. A poor ventilation situation in the case of lung diseases can also make longer anesthesia necessary.

What do the patients get?

How much a person affected in an artificial coma perceives of their surroundings depends particularly on the depth of the anesthesia. Nowadays people often try to keep the artificial coma very shallow so that the body gets rest, but the person concerned is not deeply unconscious. Experience reports show that some of those affected certainly perceive the voices of their relatives and also remember them. Sometimes they are also able to perform small movements, such as opening their eyes or moving a toe.

Many sufferers also remember nightmares during the artificial coma. This is often a side effect of the ketamine drug as it can induce hallucinations. The perception during the artificial coma is therefore very different from person to person and depends on many factors. However, since there is always the possibility that the person concerned hears and understands something, care and psychological care should not be forgotten. The famous reading aloud, which is often shown in films, can actually have a positive effect on relatives. In the same way, pleasant smells such as your favorite perfume or touch can also be perceived.

Duration of the artificial coma

The duration of an artificial coma is very variable and depends on many factors. Those affected are kept in an artificial coma until their physical condition is stable and the cause or underlying disease can be controlled without anesthesia. In most cases, the acute, life-threatening situation can be controlled after a few days and the anesthesia can be lifted. However, in some cases longer anesthesia is possible.

After about four weeks you try to end the artificial coma at the latest. After the intracranial pressure has stabilized, there are hardly any reasons to maintain the artificial coma in the head injured. In theory, an artificial coma can be sustained for a very long time, but in most cases the anesthesia will only last for a day or two. The longer the artificial coma, the higher the risk of consequential damage.

Duration of the wake-up phase

The waking up phase is a very critical time and must be closely monitored. The duration of this waking up phase depends on the anesthetics used, the underlying disease and the duration of the artificial coma. The medication is only slowly reduced and not suddenly discontinued, and even after discontinuation, the active ingredients are still present in the patient's body for a while. The ventilation is also slowed down, because the body, especially after a long period of anesthesia, first has to learn to control all body functions again. In addition to breathing, this also includes blood pressure, heart rate and the salt and water balance.

The waking up process therefore means great stress for the still weakened body. Since an incision in the trachea is often made in the case of a particularly long artificial coma, this lengthens the weaning process from the ventilators and thus the waking up phase. From a medical point of view, the wake-up phase ends with pulling the ventilation hose. For the affected relatives, however, the perceived period is longer, as the patients initially suffer from memory problems and are still confused. The relatives tend to assume that the end of the waking up phase is when communication with the relatives is possible.

How long can the artificial coma be maintained?

The artificial coma is a normal general anesthetic that is maintained for a longer period of time. Theoretically, there is no time limit for this type of anesthesia. However, the consequential damage and complications increase significantly if the anesthesia is maintained for longer. In addition, those affected develop a habit of the medication, so that a dose increase is often necessary. This is only possible to a certain extent.

Usually an artificial coma is not sustained for more than four weeks. In most cases the artificial coma will end after a few days. The treating physicians try to keep the duration of the artificial coma as short as possible and still give the body time for the underlying disease to stabilize. An attempt to wake up is started after four weeks at the latest, but this is terminated when the intracranial pressure rises again. In this case, anesthetic drugs are given again and the attempt to wake up is repeated later.

For more information, see: general anesthetic

How long are you confused after waking up?

The state of confusion, also called passage syndrome, after an artificial coma can be very different. Some sufferers are completely oriented again after a few hours or days, while others suffer from memory disorders for several weeks. In rare cases, a permanent disorder develops. The state of confusion is influenced by the age, the general condition of the person concerned and the duration of the anesthesia. Alzheimer's patients are particularly badly affected.

Further information on this topic can be found at: Continuity syndrome

Risks of Artificial Coma

The risks of an artificial coma are the same as with normal general anesthesia. However, the likelihood of complications increases with the duration of the artificial coma. The first risks already exist when the anesthesia is initiated. An intolerance to one of the anesthetic drugs or a difficult ventilation situation is possible. This can lead to an insufficient supply of oxygen if the anesthetist cannot check the ventilation in good time. Tooth damage can also occur during intubation.

The risks of a longer duration of anesthesia are to be equated with the risks of a long stay. There is a risk of thrombosis, a blood clot that can block blood vessels, which can develop into pulmonary embolism in the lungs. This is an acutely life-threatening situation as not enough oxygen is reaching the organs. Long lying periods also increase the risk of pneumonia, which can also be life-threatening in people who are already weakened. In rare cases, the controlled artificial coma can develop into a real coma, the end of which can no longer be brought about in a controlled manner. In addition to the risks of the artificial coma, complications of the underlying disease must always be expected for those affected.

Further information on this topic is available at: Risks of general anesthesia and tube feeding

Consequential damage from an artificial coma

As with shorter anesthesia, long-term anesthesia is also associated with possible long-term effects and complications. The likelihood of long-term effects increases with the depth of the anesthesia and the length of the anesthesia, which is why the artificial coma leads more often to long-term effects than short-term anesthesia during operations. The person's age and underlying disease also have a major impact on the likelihood of complications.

A frequent consequence of anesthesia, and thus also of an artificial coma, is a continuity syndrome. These are states of confusion after waking up from a coma. In most cases this condition disappears within a few days, but especially after a long artificial coma, the period of the continuity syndrome is also prolonged. Those affected report several weeks in which they have difficulty concentrating and memory gaps and sometimes fail to recognize relatives. In some people affected, this condition is also expressed through aggressive behavior, which is why restraint is often used to protect the person concerned in the waking up phase.

Another complication can come from interactions with the patient's previous medication. Since an artificial coma is used for severe injuries, it is often not possible to discuss and plan the anesthesia in detail and the anesthetist does not know the patient's history. The consequences can go in all directions, depending on the type of medication. For the same reason, the person concerned is not always sober, which can lead to a difficult ventilation situation. In both cases it is a question of the consequences of general anesthesia in general and not specifically of long-term anesthesia. The interactions can also lead to a slipping into a real coma, which cannot be ended by tapering off the medication. This is a normal protective function of the body on the stressful and threatening situation.

Further physical complications can arise, especially during the waking up phase. Since all body functions are artificially controlled during the artificial coma, the body can have problems taking over these functions itself. This particularly includes the regulation of breathing, blood pressure and heart rate. Furthermore, the long length of stay can lead to thromboses, blood clots in the legs or other blood vessels, which are usually prevented in a targeted manner by medication. Such a thrombosis can also lead to pulmonary embolism, which is an acute emergency.

The long-term consequences of an artificial coma can only be assessed when all drugs have been broken down by the body. The consequential damage of the underlying disease can only be assessed after the effects of anesthesia have subsided. In the case of brain injuries or a lack of oxygen in particular, a neurological check must then be carried out to determine which consequences the person affected will continue.

Read more on this topic at: Aftermath of anesthesia

Tracheal incision

Normal anesthesia ventilation is a breathing tube that is inserted through the mouth into the windpipe. This can be used well in the case of a brief artificial coma that is planned to wake up after a few days. However, this breathing tube irritates the mucous membranes in the mouth and throat and can lead to pressure points and open wounds in the mouth. For this reason, incision of the trachea is often used in the event of a prolonged artificial coma.

A small incision is made in the front of the neck and a ventilation tube is placed directly in the windpipe. Especially in older people who have a tendency to pressure sores due to circulatory disorders, this is a way of protecting the mouth and throat and preventing such ulcers. Furthermore, the vocal cords are spared, as the normal ventilation hose is also passed through the glottis while the tracheal incision is made below the glottis. Ventilation via a tracheal incision is tolerated even by awake people and can continue to be used after the end of the artificial coma, depending on the underlying disease.

Read more on this topic at: Tracheal incision

Artificial coma after pneumonia

If you have severe pneumonia and have difficulty breathing, ventilation may be necessary to provide the body with adequate oxygen. To do this, a ventilation tube must be pushed through the glottis into the windpipe. A person who is awake cannot tolerate this breathing tube. Nausea and panic reactions would occur. For this reason, the affected person can be placed in an artificial coma for the acute phase of pneumonia.

The body is given time to heal and receives sufficient oxygen so that the brain and other organs are not undersupplied. However, the artificial coma is the maximum level in the treatment of pneumonia and not the standard therapy. In most cases, drug therapy combined with bed rest and, if necessary, oxygen is sufficient. The maximum therapy can be necessary especially in vulnerable groups of patients, such as small children, old people and immunocompromised people.

Further information on this topic can be found at: lung infection

Artificial coma after a heart attack

A heart attack leads to an insufficient supply of oxygen to the heart muscle and thus possibly to cardiac arrest. After such a heart attack, as a result of which the person affected may even have to be resuscitated, the heart is still very weak and other organs, such as the brain, can also be damaged by the lack of oxygen as a result of the cardiac arrest. In order to avoid stress reactions of the body and to enable safe ventilation, the person affected can be placed in an artificial coma.

Another advantage of this artificial coma is that doctors can monitor body functions, such as blood pressure and heart rate, more safely and influence them with medication. Psychological stress, which can have a strong influence on body functions, can also be prevented by a deeper artificial coma. The body thus has the opportunity to heal independently of the outside world and to get used to the new situation, such as a bypass or a pacemaker. Unless cardiac arrest as part of the heart attack has occurred, an artificial coma after the heart attack is usually not necessary.

Read more on this topic at: Therapy of a heart attack

Artificial coma after an operation

There are several possible reasons for an artificial coma after an operation. First of all, these reasons can be divided into two groups. The first group are the planned cases. These are serious interventions, such as operations on the brain or heart, where it is clear even before the operation that the person concerned must be placed in an artificial coma in order to fully recover.

The second group of causes concerns complications in normally less problematic operations. The artificial coma is particularly necessary for operations on the brain in order to prevent an increase in intracranial pressure. Most other surgeries are a reduction in the body's stress response. Inflammation is prevented and strong fluctuations in blood pressure and other body values ​​are limited.

Read more on this topic at: Increased intracranial pressure

The advantage of operations is that the anesthesia does not have to be started again, but can simply be continued. This reduces the risks at the onset of the artificial coma. Ventilation is already safely possible and the person concerned already has access to medication. Furthermore, especially in the case of planned operations, it is already known whether the person concerned tolerates the anesthetic drugs well. The artificial coma can therefore be better adjusted and controlled.

Artificial coma after cardiac arrest and resuscitation

In the case of cardiac arrest, a severe lack of oxygen in the brain and all other organs occurs within a few minutes. The brain reacts quickly to a lack of oxygen with an inflammatory response, which includes swelling. Since there is little room in the skull for swelling, this leads to increased intracranial pressure and further damage to the brain. An artificial coma is possible to prevent this reaction. The oxygen supply can be secured and the stress on the body can be reduced. In an artificial coma, intracranial pressure can also be continuously monitored using a probe.

If the reason for the cardiac arrest is unknown, further examinations can take place during this time. The time to wake up and the later state of health depend heavily on how long the brain had to get along without oxygen. In the case of direct resuscitation in the hospital, the consequential damage is usually less than that of those affected who suffer cardiac arrest at home and have only waited for the ambulance service. Cardiopulmonary resuscitation by relatives is very important here. The emergency services often initiate an anesthetic on site in order to protect the person's body and to control the body's functions.

Read more on this topic at:

• Cardiac arrest
• resuscitation

Which drugs keep the artificial coma going?

The artificial coma is basically a normal general anesthetic. This consists of drugs that reduce consciousness, pain perception and muscle function. Propofol is most often used for the restriction of consciousness. Pain reduction is achieved with opiates such as morphine, fentanyl or sufentanyl.Relaxing drugs such as succinylcholine are used for muscle function. In contrast to short-term anesthesia, medication is usually administered via the veins and no additional anesthetic gas is used.

Read more on the subject at: Anesthetic and nasogastric tube

cramps

During the artificial coma, cramps are rare, as the muscle work is influenced and suppressed by drugs. The waking phase is more critical with an artificial coma. The body must first relearn its normal functions, including control over the muscles, and this can lead to excessive reactions. Furthermore, many strong drugs have an impact on brain function and can trigger convulsions. In addition, there is the underlying disease, which can be, for example, an undersupply or injury to the brain. The anesthetic medication can suppress cramps, so that these can only occur in the waking phase when weaning from the medication.