A disturbance of consciousness

Consciousness is a complex philosophical concept used in a variety of fields of knowledge (for example, legal, historical consciousness, etc.). In medicine, the concept of consciousness is one of the fundamental ones. Disorders of consciousness can be a manifestation of a variety of diseases and pathological conditions, so doctors of many specialties encounter it. Most often, issues related to diagnostics, differential diagnostics and treatment of disorders of consciousness have to be resolved by a neurologist.

Normal consciousness (clear consciousness) means adequate perception of the surrounding world and one’s own “I” (full orientation in space, time, one’s own personality), the ability to productively interact with the surrounding world and cognitive activity.

Consciousness is the result of the integrative activity of the entire brain, therefore the spectrum of changes and disorders from a normal state of consciousness to its absence (coma) is extremely wide and depends to a large extent on the “point of application” of the damaging factor.

When characterizing the state of consciousness, it is necessary to distinguish two main aspects: the level of wakefulness and the substantive, cognitive component of consciousness. The state of wakefulness is provided mainly by the activating function of the reticular formation of the brainstem and the limbic system, while cognitive activity is the function of the cerebral hemispheres. Both of these components are closely interconnected, however, it is obvious that adequate cognitive activity is impossible without a sufficient level of wakefulness, provided by more ancient mechanisms and therefore significantly less dependent on mental activity. The main criterion for wakefulness, or "awakenability", of a patient is considered to be the reaction of opening the eyes to sound or pain irritation (preservation of reactions at the level of the midbrain). If this reaction is preserved, the patient's state cannot be classified as unconscious. In pathological conditions, various combinations of the depth and structure of disorders of wakefulness and cognitive functions are possible, which creates objective difficulties in classifying disorders of consciousness and explains the multitude of terms used to characterize them, sometimes contradicting each other. Thus, a patient with gross aphasic disorders may be in a state of active wakefulness, but his cognitive activity and interaction with the outside world are undoubtedly limited. Nevertheless, it is difficult to classify such a patient as a patient with impaired consciousness. On the contrary, some patients after coming out of a coma, that is, a state in which wakefulness (awakening) and perception of the outside world are absent, talk about what happened around them. The latter fact is currently confirmed by functional MRI in patients in a state of coma, which records the activation of certain parts of the cortex when the corresponding stimuli are presented. Nevertheless, the state of such a patient must be assessed as unconscious.

Disorders of consciousness are differentiated by etiology, rate of development (acute, gradually increasing, wave-like), duration (acute, subacute, chronic), depth, content (productive and unproductive).

Impaired consciousness is understood as a disorder of reflection of the environment, objects, phenomena and their connections, manifested by a complete impossibility or indistinctness of perception of the environment, disorientation in time, place, surrounding persons, one's own personality, incoherence of thinking. Impaired consciousness can be caused by both primary diseases of the brain and secondary lesions of the central nervous system, developing with impaired cerebral circulation (transient disorders due to vascular spasm, as well as hemorrhage or ischemia of the brain), pathology of internal organs or exogenous intoxication. Impaired consciousness is conventionally divided into two groups - depression and alteration of consciousness.

• Depression of consciousness - unproductive forms, characterized by a deficit of mental activity, a decrease in the level of wakefulness, suppression of intellectual functions and motor activity. These include stupor, stupor and coma (with some reservations - and stupor). With severe depression of consciousness, vital functions are disrupted.
• Changes in consciousness develop against the background of wakefulness and are characterized by a disorder of mental functions, a distorted perception of the environment and one’s own personality.

Assessing the state of consciousness is the first element of a general examination performed by a physician.

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Classification of depression of consciousness

The following types of depression of consciousness are distinguished.

• Stupor is a state of numbness; when emerging from this state, the patient does not answer questions meaningfully enough.
• Stupefaction is a form of clouding of consciousness, characterized by an increase in the threshold of all external stimuli, a slowdown and difficulty in the flow of mental processes, a paucity of ideas, and an incomplete or lack of orientation in the surrounding environment.
• Sopor is a deep stage of stupor, in which there are no reactions to verbal communication and only reactions to painful stimuli are preserved.
• Coma is a state of profound depression of the central nervous system functions, characterized by complete loss of consciousness, loss of response to external stimuli and disruption of the regulation of vital functions of the body.

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Forecast

The outcome of patients with impaired consciousness, especially those in a coma, depends on many factors. The accuracy of the prognosis is determined primarily by the etiology of the lesion and the degree of depression of consciousness, so it is advisable to discuss the prognosis and outcome of the disease only in connection with the specific condition of the patient. In general, in addition to the cause of the coma, the patient's age, speed and volume of medical care are of great importance.

A patient with impaired consciousness, especially in a coma, requires quick decisions, since with timely diagnosis and adequate therapy, coma can be reversible, while delay in some cases can be fatal.

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