Generality
The coma, or comatose state, is a state of unconsciousness, from which those who fall into it cannot be awakened; this condition - characterized by the lack of response to painful stimuli, light changes and sounds - undermines the sleep-wake cycle and makes any voluntary action impossible.
The severity of a coma and its modes of onset depend on the triggering causes.
Generally and unless the patient wakes up, the state of coma proper has a limited duration in time, ranging from 4 to 8 weeks. After that, it evolves either in a vegetative state or in a state of minimum consciousness.
The passage from the coma to the vegetative state or to the least conscious one can decree or not a progressive improvement of the patient's health conditions.
The improvements deriving from the exit from the state of coma are unpredictable, they can be more or less fast and depend on the severity of the encephalic damage that originally caused the comatose state.
In its early stages, the hospitalization of a comatose person takes place in the intensive care unit; therefore, when the patient's condition has stabilized to a certain degree, it occurs in the ward.
What is a coma?
The coma is a state of unconsciousness, from which those who fall into it cannot be awakened; this condition entails the lack of response to painful stimuli, changes in light and sounds, makes the sleep-wake cycle jump and, finally, makes any voluntary action impossible.
A subject who falls into a coma is called a " comatose subject ". The adjective comatose is also valid associated with the word "state"; comatose state and coma are synonymous.
COMA AND PHARMACOLOGICAL COMA: ARE THE SAME WHAT?
Coma and pharmacological coma are two distinct situations, which should be clarified from the very beginning of this article.
While the coma is a state of unconscious pathological unconsciousness and indicative of a serious health condition, the pharmacological coma is a state of unconsciousness induced voluntarily by doctors, to favor recovery from traumatic situations, to protect the brain from a deficiency of oxygen and to reduce the sensitivity to pain, during very delicate surgical interventions.
Also known as induced coma or artificial coma, the pharmacological coma is obtained with controlled doses of barbiturates, benzodiazepines or propofol, in addition to opiate analgesics (eg morphine).
ORIGIN OF THE NAME
The term "coma" comes from the Greek word " koma " ( κῶμα ), which means " deep sleep ".
Causes
There are many reasons why a person can go into a coma.
The possible causes of coma include:
- Intoxications from abuse / overdose of drugs, hard drugs, harmful substances or alcohol. According to reliable medical investigations, 40 cases of coma out of 100 (thus 40%) would be due to a pharmacological poisoning.
- Severe metabolic abnormalities;
- Diseases of the central nervous system at an advanced stage;
- Stroke and brain hernia;
- Serious brain trauma;
- Hypothermia;
- Hypoglycemia;
- Severe hypercapnia;
- Eclampsia.
WHEN A PERSON ENTERS COMA?
In the human brain, there are two nerve components whose correct functioning is fundamental for maintaining the state of consciousness: the cerebral cortex, in which the so-called gray substance resides, and a structure of the brainstem, called the reticular activation system (RAS ).
The entry into a coma by an individual takes place when one or both of the aforementioned nerve components (ie cerebral cortex and / or RAS) suffer damage.
How drug abuse causes coma and what effects it causes
Improper drug intake causes damage to the so-called reticular activation system (RAS), which, at this point, stops working properly.
Before leading to coma, the lack of functioning of RAS due to pharmacological intoxication involves: a sensitive alteration of the cardiac rhythm and arterial pressure, irregular breathing and profuse sweating.
Features
The severity of the coma and the modes of onset depend on the triggering causes.
For example, taking into consideration only the modes of onset, the coma resulting from hypoglycemia or hypercapnia includes a series of previous symptoms, including: agitation, confusion, progressive blunting and stupor; on the contrary the coma resulting from a head injury or a hemorrhagic stroke at the subarachnoid level ( subarachnoid hemorrhage ) is instantaneous.
The modes of onset of coma represent an important diagnostic fact, which helps doctors to understand what may have triggered the comatose state.
HOW TO ESTIMATE THE GRAVITY OF A COMA?
There are various measurement scales to estimate the severity of a coma. The most famous and most widely used measurement scale today is the so-called Glasgow Coma Scale ( GCS scale ). The GCS scale includes a range of values ranging from a minimum of 3 - a value that represents the deep coma - to a maximum of 15 - a value that represents the maximum consciousness .
The parameters considered by the GCS scale, to assess the severity of a coma, are three: the opening of the eyes, the motor response to a given command and the verbal response to a certain vocal stimulus . Each of these parameters corresponds to a numerical interval (in English score ), which indicates its severity.
To understand:
- The opening of the eyes has a score ranging from 1 to 4. 1 (one) indicates complete absence of eye opening; is the most serious level. 4 (four), instead indicates spontaneous ocular opening; equivalent to normality.
Intermediate values correspond to intermediate situations.
- The motor response to a given command has a score that goes from 1 to 6. 1 (one) reports complete absence of motor response to any command; is the most severe level. 6 (six), on the other hand, indicates maximum motor obedience to any command; corresponds to normality.
Values between 1 and 6 represent intermediate situations.
- The verbal response to a certain vocal stimulus has a score that goes from 1 to 5. 1 (one) indicates complete absence of response to any type of verbal stimulus; is the most serious level. 5 (five), on the other hand, indicates maximum attention, normal language ability and ability to respond to any verbal stimulus; represents normality.
As in the previous cases, the values included between 1 and 5 are equivalent to intermediate situations.
The estimate of the severity of a coma is the result of the sum of the points assigned to each of the aforementioned parameters. For example, if in a medical investigation the opening of the eyes, the motor response to a command and the verbal response to a vocal stimulus total the minimum each (ie 1), the evaluation of the coma is equal to 3 (the situation more severe, equivalent to deep coma).
At this point, there is one last important aspect to be clarified: in the GCS scale there is a threshold value that represents the borderline between the state of coma and the state of consciousness . This value is 8 . Thus, when the sum of the GCS parameters is greater than 8, the individual is more or less conscious; when instead the sum of the GCS parameters is equal to or less than 8, the subject is in a more or less deep state of coma.
DURATION OF THE COMA
Unless the person concerned wakes up, the true coma has a canonical duration of between 4 and 8 weeks . Then it evolves and, depending on the seriousness of the triggering causes, it can become: vegetative state or state of minimum consciousness .
A person in a vegetative state is a person awake unaware of himself and of the environment in which he finds himself; a person in a state of minimum consciousness, on the other hand, is a waking subject who, at times, is also aware.
It is very rare for a state of coma to last for more than 8 weeks. In fact, in the absence of awakening or transition to the vegetative state or state of minimum consciousness, it is easier for the patient to die.
RECOVERY FROM THE COMA
Recovery from a state of coma varies from individual to individual . In fact, for some, entry into the vegetative state or state of minimum consciousness does not coincide with other improvements or coincides with minimal improvements; for someone else, however, it represents the beginning of a gradual process of restoring normal encephalic functions (cognitive abilities, motor skills, etc.).
When it takes place, the restoration of normal brain functions can be more or less fast. The speed of restoring normal brain functions depends on various factors, including:
- The severity of the cause that caused the brain damage and the resulting coma;
- Age and general state of health of the patient;
- Duration of coma;
- Ability of doctors and other therapists (eg, physiotherapists), who take care of the patient.
HOSPITAL ENVIRONMENTS
People in coma need medical care that only a hospitalization can provide.
In its early stages, the hospitalization of a comatose person takes place in the intensive care unit . In this phase, intensive care is essential, as the onset of coma represents the most delicate and needy moment of attention by medical personnel.
Subsequently, when the patient's condition has stabilized, hospitalization is held in the ward . Here, doctors will mainly provide maintenance, recovery and prevention therapies.
Diagnosis
The diagnosis of coma is not only the ascertainment of the comatose state - which is usually a simple finding - but it is also the identification of the triggering causes .
The identification of the causes of the coma can also be very complex, so as to require the use of various diagnostic tests.
Among the possible diagnostic tests useful for the discovery of the conditions at the origin of a state of coma, include: the physical examination, the medical history, the CT scan, the nuclear magnetic resonance ( MRI ), the electroencephalogram, etc.
The typical steps of the diagnosis of coma and its causes
- Physical examination and evaluation of clinical history;
- Verification of the state of coma. There are specific tests that allow doctors to ascertain whether an individual is in a coma;
- Search for the damaged brain site, which led to coma;
- Evaluation of coma severity, through the Glasgow Coma Scale scale ;
- Analysis of a patient's blood sample, to understand if at the origin of the coma there can be a pharmacological intoxication;
- Analysis of blood levels of glucose (glycaemia), calcium (calcemia), sodium (sodium), potassium (kaliemia), magnesium (magnesium), phosphate (phosphataemia), urea and creatinine;
- Brain scans, via CT or nuclear magnetic resonance;
- Monitoring of encephalic functions, through encephalogram.
Treatment
Coma doctors and experts have not yet identified a medicine or a particular instrument capable of awakening a person in a comatose state.
Having said this, those in a coma receive numerous treatments, the purpose of which is manifold and varies from safeguarding vital functions - such as breathing or blood circulation - to supplying the body with all the nutrients necessary for the survival and maintenance of a good state of health.
In addition, comatose people need special medical care, which is used to prevent infectious diseases (primarily aspiration pneumonia ) or to prevent problems such as bedsores, atelectasis, etc.
Finally, readers are reminded of the existence of a therapeutic guide for people who came out of the coma, whose goal is to help them return to a normal or almost normal life.
HOW DO THE COMATOSI SUBJECTS BREATHE?
In subjects in coma, mechanical ventilation through intubation supports breathing.
HOW TO PREVENT SUCTION PULMONITE
In the case of coma, aspiration pneumonia is a complication that may depend on several factors, including:
- Gastroesophageal reflux, resulting from prolonged maintenance of a horizontal position;
- The inability to swallow correctly;
- Tube feeding.
To prevent the complication in question, the most practiced medical remedies consist of:
- Maintaining the patient in a lateral position;
- Saliva aspiration at regular intervals;
- Parenteral nutrition.
HOW TO PREVENT DECUBITUS PLEASURES
Briefly, pressure sores are lesions that typically appear in people who, forced to immobility for long periods of time, maintain a static position.
Pressure sores are a possible consequence not only of coma, but also of fractures in the limbs, castings in several parts of the body, severe obesity or risky pregnancy.
To prevent pressure sores, it is essential:
- Change the position of the patient bedridden every 2-3 hours;
- Use water mattresses, which are more congenial to those who are forced to spend long periods of immobility;
- Plan nutrition appropriate to the needs of the human body;
- Monitor favorable conditions, such as diabetes.
THERAPEUTIC GUIDE FOR PEOPLE GIVEN FROM THE COMA
People who wake up from a state of coma need some care, which - as anticipated - encourages a return to a normal life.
The care in question includes:
- Physiotherapy, essential to remedy muscle contractions, resulting from prolonged immobility;
- Occupational therapy, whose field of application ranges from favoring the reintegration of the patient, in a social context, to adapting the home environment according to the needs of the person just awakened from the coma;
- Psychotherapy, whose goal is to help the patient to overcome the early stages of awakening from the comatose state and to accept irrecoverable incapacities, which the resulting brain damage and coma may have caused.
CURIOSITY
On the basis of several scientific studies (in particular, one dating back to 2002), some doctors claim that a treatment particularly indicated in the case of post-cardiac arrest would be induced hypothermia .
In medicine, the term hypothermia indicates the lowering of body temperature below the physiological average.
Prognosis
The prognosis in case of coma varies from patient to patient and depends, mainly, on the triggering causes, on the health conditions in which the patient was before entering the comatose state and on the extent of the neurological damage.
Even for the most experienced doctors, any prediction of the evolution and long-term consequences of a coma is quite complex.
