Symptoms of impaired consciousness

Variants of impaired consciousness

Below are some concepts used to refer to disorders of consciousness. The definitions of these concepts may differ from one author to another.

Acute and subacute disorders of consciousness

Darkening of consciousness - with a slight decrease in the level of wakefulness, the perception and evaluation of the environment is reduced and distorted. There may be excitement, delirium, hallucinations, various affects, in connection with which the patient can make inadequate actions. Typical for intoxication, psychosis. It can precede the development of a coma.

Confusion is characterized by a violation of the sequence and a slowing down of all mental processes, memory, attention. Typical disorientation in place, time, personal situation. The level of wakefulness is reduced slightly. It can be a consequence of intoxication, intracranial hypertension, acute and chronic circulatory disorders and other conditions.

Twilight consciousness is a peculiar state when the perception and awareness of the surrounding reality is sharply limited or completely absent, but the patient is able to perform a series of unconscious successive habitual actions. The most typical example is an epileptic seizure in the form of complex automatisms. Similar conditions can also be found in acute transient circulatory disorders (states like global amnesia).

Delirium is an acute disturbance of consciousness, manifested primarily by excitation, disorientation in the environment and a violation of perception of sensory stimuli, sleep-like hallucinations, during which the patient is absolutely inaccessible to contact. A patient in a state of delirium can be aggressive, verbose, suspicious. The flow of the delirious state is wavy, with relatively light intervals, during which elements of contact and criticism appear. The duration of delirious condition usually does not exceed 4-7 days. It occurs in exogenous and endogenous intoxications, including alcoholic, as well as with severe craniocerebral trauma in the stage of getting out of the coma.

Stunning is a condition in which the level of wakefulness is significantly reduced in the absence of productive symptoms. Speech contact with the patient is possible, but it is essentially limited. The patient is languid, sleepy, mental processes are slowed down. Characterization of disturbance of orientation, memory. At the same time the patient performs various motor tasks, the physiological position in the bed is preserved, complicated motor acts are complicated. Typical fast exhaustion.

Distinguish between moderate and deep stunning. The boundary between these states is very conditional.

• With moderate stunning, the speech activity of the patient remains in the form of answers to questions, although the speech is monosyllabic, emotional coloring is absent, responses are slow, often they can be obtained only after repeated repetition of the question.
• With deep stunning, the decrease in wakefulness increases, the patient's speech activity is almost non-existent, but the understanding of reversed speech persists, which is manifested in the performance of various motor tasks. When differentiating the state of stunning, it should be remembered that the cause of speech impairment may be focal lesion of the temporal lobe of the dominant hemisphere.

Sopor is a condition that in translation means "deep sleep". Under a co-morbid state, one usually understands the deep depression of consciousness with the development of pathological sleep. There are no instructions. Nevertheless, the patient can be "awakened", that is, to receive a reaction of opening the eyes to sound or pain. Vital functions, as a rule, are not significantly disturbed. A mimic and purposeful coordinated motor reaction to the corresponding strong irritation, for example, to the pain stimulus, has been preserved. There are various stereotyped motions, motor anxiety in response to irritation. After the stimulus ceases, the patient is again immersed in a state of areactivity.

Stupor - in the English-speaking literature concept, almost similar to the comparison. They are also used to refer to psychogenic isactivity, which occurs as an element of a complex symptomatic complex in catatonia (catatonic stupor).

Coma (coma). The main manifestation of a coma - a virtually complete absence of signs of perception and contact with others, as well as mental activity (areactivity). The patient lies with his eyes closed, it is impossible to "wake him up" - there is no reaction of opening the eyes to sound or pain. For all other signs (the position in bed, spontaneous motor activity, reaction to various stimuli, the degree of preservation of stem functions, including vital, the state of the reflex sphere, etc.), coma states are extremely diverse. The neurological symptom complex of a comatose patient consists of various symptoms of irritation and loss, depending on the etiology of the lesion, its localization and severity.

Not every brain damage, even very extensive, causes coma. A necessary condition for the development of this state is the damage to structures providing wakefulness. In this regard, comatose states with supratentorial pathological processes are possible only with significant bilateral damage involving activating conducting systems that go from the reticular formation and the visual hillock to the cerebral cortex. The fastest coma develops when the damaging factor is affected by the medial and medio-different parts of the midbrain. In the case of damage to the subtentorial structures, coma states develop as a result of primary or secondary impairment of the brain stem function and are primarily due to the effect on the oral sections of the reticular formation. The close functional relationship of the reticular formation to the nuclei of the scapular nerves, providing vital functions (respiratory and vasomotor centers), causes a typical rapid damage to the breathing and circulation of the stem. The development of coma is typical for acute pathological processes in the brain stem (circulatory disorders, craniocerebral trauma, encephalitis). With slowly progressing diseases, long-term compensation (tumors and other volumetric processes of the posterior cranial fossa, including brainstem, multiple sclerosis, syringobulbia) is possible.

Chronic disorders of consciousness

Chronic disorders of consciousness are usually called states formed in the outcome of acute disorders. A clear time line between acute, subacute and chronic disorder of consciousness is absent. Chronic is considered to be a condition that was formed about a month after a disturbance of consciousness appeared. Criterion of chronic disorder should also be considered stabilization of the state at a certain level and the absence of changes in one direction or another for a fairly long (not less than a few days) time interval.

Vegetative state (vegetative status, wakeful coma, apallic syndrome). The above terms describe a condition characterized by relative preservation of stem functions with complete absence of signs of functioning of the cerebral hemispheres. The vegetative state, as a rule, develops as a coma outcome. Unlike the latter, it is characterized by a partial, stable or unstable recovery of the awakening reaction in the form of spontaneous or induced opening of the eyes, the appearance of a change of sleep and wakefulness. Spontaneous breathing is preserved and the cardiovascular system is relatively stable. At the same time, there are no signs of contact with the outside world. Other symptoms can be very variable. Thus, motor activity may be completely absent or manifest as a mimic or non-purposeful motor reaction to pain; can be preserved chewing, yawning, involuntary phonation (moaning, crying), reflexes of oral automatism, grasping reflex. There are various changes in the muscle tone in a pyramidal or plastic type. The clinical picture corresponds to the morphological changes in the brain, the absence of micro-focal changes in the trunk is characteristic with pronounced extensive bilateral changes in the terminal brain, especially its anterior medial divisions, or these changes are insignificant.

The vegetative state can be a stage of the patient's exit from a coma. In such cases, as a rule, it is short-lived, soon it becomes possible to contact the patient (the first signs are fixation of eyes, tracking, reaction to speech). However, the complete restoration of mental functions in a patient who survives a vegetative state, almost never occurs.

In the absence of positive dynamics, the vegetative state may persist for many years. Its duration depends mainly on good care of the patient. The death of a patient usually comes as a result of infection.

Akinetic mutism is a condition in which a patient who has all the signs of a rather high level of wakefulness, the preservation of stem functions, the elements of contact with the outside world (the awakening reaction, the change of sleep and wakefulness, the fixation of the gaze, the tracking of the object), shows no signs of motor and speech activity, both spontaneous, and in response to the stimulus. There are no signs of damage to the motor ways or speech zones, which is proved by the cases of complete recovery of motor and speech activity with a favorable outcome of the disease. The syndrome develops, as a rule, with a bilateral lesion of the medial parts of the hemispheres involving reticulocortical and limbic-cortical pathways.

Dementia is a condition in which, with a high, high level of wakefulness, severe stable or steadily progressing disorders of mental activity are revealed (a substantial, cognitive component of consciousness). Dementia is the outcome of many extensive and diffuse organic lesions of the cerebral cortex (outcomes of craniocerebral trauma, acute and chronic circulatory disorders, prolonged hypoxia, Alzheimer's disease, etc.).

The lock-in syndrome is described by F. Plum and J. Posner in 1966. It occurs with extensive cerebral infarctions on the basis of the bridge. Characterized by the complete absence of voluntary motor activity, with the exception of eye movements in the vertical direction and flashing. These movements provide contact with the patient. Syndrome in the strict sense of the word is not considered a disorder of consciousness, but it is necessary to know it, since the state of isolation is often confused with a coma or a state of akinetic mutism.

Death of the brain is a condition in which all the functions of the brain are lost. Characterized by complete loss of consciousness, lack of independent breathing, a tendency to arterial hypotension, diffuse muscular atony, areflexia (individual spinal reflexes may persist), bilateral fixed mydriasis. In conditions of safe operation of the heart and ventilation, with appropriate care, the patient's life can be prolonged for a fairly long time. The problems associated with determining the criteria for brain death are extremely complex, especially from the ethical point of view. In many countries, these criteria are summarized in specially adopted protocols. Determination of brain death is of great importance for transplantology.

[1], [2], [3], [4]