The term “coma” comes from the Greek and means “deep sleep”. It is therefore not an illness in itself, but a symptom of various diseases. The coma represents the most severe form of a disturbance of consciousness.
Consciousness is the ability to perceive one’s surroundings (i.e. external stimuli, other people, etc.) and to interact with them. In general, there are 5 degrees of consciousness: 1. clarity of consciousness, in which the environment is perceived normally and there are no impairments, 2. drowsiness, in which even slight limitations in perception exist and the person affected shows a certain drowsiness, 3.
Somnolence is then already a more pronounced drowsiness, in which the affected person can still be awakened, 4. sopor as pronounced drowsiness from which the affected person can hardly be awakened at all, and finally 5. coma, a state in which the affected person can no longer be awakened by any kind of external stimuli, not even pain stimuli. Coma is the consequence of a serious disturbance of the function of the cerebrum and is usually a life-threatening condition. The “artificial coma” must be distinguished from the actual coma.
The term is not entirely correct in this respect, since the limitation of consciousness is deliberately induced by medication and is also completely reversible after the medication has been discontinued. In the medical sense, the term coma should be reserved for an unregulated unconsciousness. There are different ways of classifying coma into different degrees or classes, usually based on medical considerations.
The most common classification of coma is in 4 degrees: 1st degree: The patient shows reactions to pain in the form of targeted defensive movements (but without waking up) the puppets shrink when a light stimulus is given, even an irritation from the organ of balance still triggers the corresponding eye movements (the so-called vestibulo-ocular reflex). 2nd degree: The patient now only deflects pain stimuli in an undirected manner by means of so-called mass movements, but the pupillary reflex is still present; at most, squinting outwards may be conspicuous. 3rd degree: The defensive reaction against pain is completely absent, if at all, slight undirected movements take place, the vestibulo-ocular reflex is now missing and the pupil reaction is only weakly preserved.
4th degree: There is no longer a reaction to pain, the pupils are dilated and no longer narrow when exposed to light. The “Glasgow Coma Scale” has continued to prove its worth, although it also includes the less serious disturbances of consciousness and is primarily used for an initial assessment on the spot, thus making it easier to make a decision in an emergency. This scale assigns different points in the 3 categories “eye opening”, “verbal communication” and “motor reaction”. The maximum number of points to be achieved is 15, the minimum number is 3, which then indicates a deep coma. A score of 8 or lower should normally be followed by ventilation, as severe impairment of brain function can then be assumed.
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