Core concept & etiology
In medical practice, a disorder of consciousness is understood as the inability of the nervous system to adequately perceive and analyze information. The patient suffers from unclear perception, and their thinking becomes incoherent. Pronounced disorientation occurs, affecting several spheres at once: a person may lose track of time, fail to recognize their location, and fail to identify surrounding people and even their own personality.
All causes for the development of such conditions are divided into two large groups:
- Primary: associated with direct damage to central nervous system structures or organic diseases of the brain itself.
- Secondary: develop as a complication against the background of other diseases. These include any cerebrovascular disorders (ischemic processes, vascular spasms, hemorrhages), severe internal organ pathologies, and exogenous intoxications of the body.
Classification principles
In internal medicine practice, all disorders are conventionally divided into two fundamentally different categories. Patient management tactics and the attending physician's specialty depend on their type.
- Suppression of consciousness (non-productive forms).
These are so-called quantitative disorders. They are characterized by a pronounced deficit of mental activity and decreased motor activity. The patient's level of wakefulness drops, and intellectual functions gradually become suppressed. The clinical danger of such conditions lies in the fact that at their maximum depth, vital functions of the body begin to suffer.
- Alterations of consciousness (qualitative disorders).
They develop against the background of fully preserved physical wakefulness. The essence of the pathology boils down to a profound mental disorder and a distortion of perception regarding both oneself and the surrounding world. The disciplinary affiliation of this group is different: such conditions are studied in detail in psychiatry courses.
Stages of impaired consciousness
The differential diagnosis of quantitative disorders is based on how deeply the patient's reactions to stimuli are suppressed and whether their contact with the external world is preserved. The following stages are distinguished as severity increases:
- Stupor. The patient still retains the ability to answer questions asked, but their answers are insufficiently meaningful. This sign is especially noticeable when the patient emerges from this state.
- Obtundation. The threshold of perception for external stimuli is sharply increased: to get a response, the physician needs very strong stimuli. The patient's mental processes are slowed down and severely impaired. Concepts become sparse, and orientation in the environment is incomplete (or completely absent).
- Soporous state (Soporous). Represents a deep stage of obtundation. Key differential sign: the patient completely lacks any reaction to verbal address, but clearly retains a reaction to painful stimuli.
- Coma. The extreme, most severe degree of profound CNS depression. Characterized by total loss of consciousness and a complete lack of reactions to any external stimuli. In coma, a critical disruption in the regulation of vital functions occurs.
Briefly: answers to topical questions
What types of qualitative disorders of consciousness exist?
Qualitative disorders of consciousness (alterations of consciousness) include the following disorders:
- Delirium;
- Amentia;
- Twilight state of consciousness;
- Oneiric state.
Which scale is used to objectively assess the degree of impaired consciousness?
To objectively assess the degree of impaired consciousness and coma, the Glasgow Coma Scale (GCS) is used.
The Glasgow Coma Scale score is made up of the sum of points across 3 parameters: eye opening, motor responses, and verbal responses.
Which specific vital functions of the body are impaired in coma?
In coma, the functions of respiration and circulation are impaired.
What types of coma are distinguished depending on etiology?
The most frequent types of coma resulting from critical homeostasis shifts:
- Uremic coma — due to the retention of nitrogenous waste products in renal failure;
- Hepatic coma — due to severe damage to the liver parenchyma;
- Diabetic coma (ketoacidotic) — in diabetes mellitus;
- Hypoglycemic coma — as a result of insulin overdose;
- Coma in traumatic brain injury (TBI);
- Alcoholic coma.
Order of depression: S-O-S-C (Stupor — Obtundation — Soporous — Coma). The further the letter is from the beginning, the more severe the condition and the deeper the deficit of mental activity.
Class and exam questions
How to quickly distinguish stupor from coma during an initial examination?
The main criterion is the response to pain. In stupor, the patient does not respond to speech, but reacts to painful stimuli. In coma, reactions to absolutely any stimuli disappear.
What is the difference between quantitative and qualitative disorders?
Quantitative disorders (suppression) manifest as a deficit of activity and decreased wakefulness. Qualitative (alterations) occur with preserved wakefulness, but with distortion of the psyche and perception of reality.
What is characteristic of the obtundation stage?
In obtundation, the threshold of perception is sharply increased: the patient requires strong stimuli to react. Their mental processes are slowed down, and orientation in the environment is incomplete or absent.
What else to study on this topic
- Types and characteristics of qualitative alterations of consciousness in psychiatry
- Mechanisms of secondary disorders development in circulatory disorders
- The impact of exogenous intoxications on brain functions
- Pathophysiology of vital functions depression in coma
- Features of disorientation in identity and space
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