The Rancho Los Amigos Scale is a complex scale that has eight separate levels, and is often used in the first few weeks or months of coma while the patient is under closer observation, and when shifts between levels are more frequent. Treatment
Treatment for people in a coma will depend on the severity and cause of the comatose state. Upon admittance to an emergency department, coma patients will usually be placed in an Intensive Care Unit (ICU) immediately, where maintenance of the patients respiration and circulation become a first priority. Stability of their respiration and circulation is sustained through the use of intubation, ventilation, administration of intravenous fluids or blood and other supportive care as needed. Continued care
Once a patient is stable and no longer in immediate danger, there may be a shift of priority from stabilizing the patient to maintaining the state of their physical wellbeing. Moving patients every 2–3 hours by turning them side to side is crucial to avoiding bed sores as a result of being confined to a bed. Moving patients through the use of physical therapy also aids in preventing atelectasis, contractures or other orthopedic deformities which would interfere with a coma patients recovery.Pneumonia is also common in coma patients due to their inability to swallow which can then lead to aspiration. A coma patients lack of a gag reflex and use of a feeding tube can result in food, drink or other solid organic matter being lodged within their lower respiratory tract (from the trachea to the lungs).
The term is found again in Thomas Willis (1621–1675) influential De anima brutorum (1672), where lethargy (pathological sleep), coma (heavy sleeping), carus (deprivation of the senses) and apoplexy (into which carus could turn and which he localized in the white matter) are mentioned. The term carus is also derived from Greek, where it can be found in the roots of several words meaning soporific or sleepy. It can still be found in the root of the term carotid. Thomas Sydenham (1624–89) mentioned the term coma in several cases of fever (Sydenham, 1685). Signs and symptoms
General symptoms of a person in a comatose state are:

Inability to voluntarily open the eyes
A non-existent sleep-wake cycle
Lack of response to physical (painful) or verbal stimuli
Depressed brainstem reflexes, such as pupils not responding to light
Irregular breathing
Scores between 3 and 8 on the Glasgow Coma Scale

Causes
Many types of problems can cause a coma. Forty percent of comatose states result from drug poisoning. Certain drug use under certain conditions can damage or weaken the synaptic functioning in the ascending reticular activating system (ARAS) and keep the system from properly functioning to arouse the brain. Secondary effects of drugs, which include abnormal heart rate and blood pressure, as well as abnormal breathing and sweating, may also indirectly harm the functioning of the ARAS and lead to a coma. Given that drug poisoning is the cause for a large portion of patients in a coma, hospitals first test all comatose patients by observing pupil size and eye movement, through the vestibular-ocular reflex. (See Diagnosis below.