A tuft of long hairs at one (or both) end(s) of a seed; seed appendage to aid wind dispersal.
A state of unconsciousness from which a patient cannot be aroused.
A severe disturbance of consciousness with absence of voluntary activity (either motor or cognitive) and diminished or absent responsiveness to tactile, thermal, proprioceptive, visual, auditory, olfactory, or verbal stimuli. Coma is indicative of widespread cerebral dysfunction and is often part of delirium.
A state of profound unconsciousness from which the patient cannot be aroused, even by powerful stimuli.
Stupor; abnormally deep sleep.
A state of profound unconsciousness from which a person cannot be aroused.
Deep and prolonged state of unconsciousness.
A state of deep unconsciousness, but unlike sleep in that the person cannot be aroused and does not respond, either to external stimuli (such as shouts or pinches) or internal (such as the sensation of a full bladder). Unlike conditions of brain death, however, some types of brain activity remain. Even severely comatose patients can sometimes breathe on their own, move their eyes, and make other facial movements. Patients in less severe comas may even have some modest response to external stimulation, even though still unconscious. People can exist for years in a coma, if feeding, breathing, and other vital functions are maintained. Coma can result from a variety of problems, including head injury, brain tumor, severe cases of diabetes mellitus, kidney and urological disorders, liver problems, encephalitis, meningitis, shock, and hypoxia.
State of profound unconsciousness, from which the person cannot be aroused, resulting from drug action, toxicity (as in nephritis), brain injury, or disease.
State of unconsciousness in which the patient cannot be aroused, even with powerful stimuli; may result from trauma, disease, or toxicity.
Accumulation of sebum and keratin in the opening of a hair follicle.
A deep unconscious state in which a person is unable to respond to stimuli such as another person’s voice or pain. It may result from trauma, illness, poisoning, or an overdose of drugs or alcohol.
A profound or deep state of unconsciousness. A coma may occur as an outcome of an underlying illness, or it may be caused by trauma. A person in a coma lacks both wakefulness and awareness. In addition to providing treatment to reverse the coma, medical care includes providing nutrition and preventing infection (especially pneumonia) and pressure sores. Physical therapy may be used to prevent permanent muscular contractions and orthopedic deformities.
A state of unrousable unconsciousness. Its severity is sometimes graded according to the presence or absence of withdrawal responses to painful stimuli and pupillary and corneal reflexes.
A state of profound unconsciousness in which the patient cannot be roused and reflex movements are absent. Signs include long, deep, sighing respirations, a rapid, weak pulse, and low blood pressure. Usually the result of a stroke, coma may also be due to high fever, diabetes mellitus, glomerulonephritis, alcohol, epilepsy, cerebral tumour, meningitis, injury to the head, overdose of insulin, carbon monoxide poisoning, or poisoning from opium and other narcotic drugs. Though usually of relatively short duration (and terminating in death, unless yielding to treatment) it may occasionally last for months or even years.
A state of unconsciousness from which one cannot be aroused. Coma is the most severe of the alterations of consciousness. It differs from sleep in that comatose patients will not awaken with stimulation; it differs from lethargy, drowsiness, or stupor (states in which patients are slow to respond) in that comatose patients are completely unresponsive. Finally, it differs from delirium, confusion, or hallucinosis (states in which patients’ sense of reality is distorted and expressions are bizarre) in that comatose patients cannot express themselves at all.
A prolonged period of deep unconsciousness that may result from a severe brain injury, a disease, or a drug overdose.
A state characterized by profound unconsciousness, wherein the individual is unresponsive and cannot be awakened.
A condition characterized by a lack of consciousness and unresponsiveness to both external stimuli, such as physical stimuli like pinching, and internal stimuli, including the sensation of a full bladder.
Coma occurs as a consequence of disruption or injury to specific brain regions responsible for conscious functioning or the preservation of consciousness. These areas primarily encompass the cerebrum, upper portions of the brainstem, and central regions of the brain, notably the limbic system.
Coma can arise from various conditions, including severe head injury, disorders like stroke or cardiac arrest that cause partial or complete deprivation of blood to the brain, and infectious disorders affecting the brain such as meningitis and encephalitis. Moreover, abnormal blood levels of certain substances, either excessively high or low, can lead to a state of coma. For instance, individuals with diabetes mellitus may experience coma if their blood glucose (sugar) levels rise or fall to an abnormal extent.
In the realm of comatose states, a wide spectrum of depths exists. Within the milder manifestations, an individual experiencing such a state may exhibit slight movements and exhibit responses to specific stimuli. Conversely, in the depths of a profound coma, no voluntary motions or reactions are observed. Nevertheless, even in the profound depths of a coma, involuntary reflexes can manifest, such as autonomous respiration and intermittent eyelid fluttering. However, when the lower brainstem incurs damage, critical bodily functions become compromised, necessitating the provision of artificial respiration and circulation maintenance.
When the extent of brain damage remains minimal and holds the potential for reversibility, an individual stands a chance of experiencing a complete restoration. Conversely, in cases of deep coma resulting from severe trauma, long-term neurological complications may arise, encompassing muscle weakness and alterations in behavioral patterns. In instances where an individual remains in a profound coma, often referred to as a persistent vegetative state, the preservation of life for extended periods becomes possible as long as the brainstem maintains its functionality. However, the irreversible and total loss of brainstem function signifies brain death, marking the permanent cessation of all cognitive faculties.
A state of absolute unconsciousness. Partial unconsciousness is called stupor. If the casualty responds to a shouted question, providing he is not deaf, he is in stupor; if there is no response he may be in coma, fainting, hysterical, or dead. If the eyelids are retracted and flutter or resist being opened the casualty is in stupor. If the pupils contract when a torch is shined into the eyes and dilate when the light is turned off, the casualty is in stupor; in coma, the pupils are unresponsive to light, and if the coma is very deep they may be widely dilated as well as unresponsive. First aid for the unconscious. Remove any dentures and ensure there is no obstruction to the breathing. Slightly raise the shoulders and keep the head turned to one side in case the patient should vomit. If the breathing is noisy and sounds as though water is bubbling in the chest, place him half on his front and half on his side. Cover him with a blanket but do not warm with a hot-water bottle. Do not give anything to drink or he may choke, and do not leave him unattended but send for a doctor.