Anesthesia, or anaesthesia is a temporary state consisting of unconsciousness, loss of memory, lack of pain, and muscle relaxation.
Anesthesia is a unique medical intervention which does not itself offer any particular medical benefit and instead enables the performance of other medical interventions. The best anesthetic is therefore one with the lowest risk to the patient that still achieves the end points required to complete the other intervention. There are many different needs and goals of anesthesia. The goals (end points) are traditionally described as unconsciousness and amnesia, analgesia, and muscle relaxation. To reach multiple end points one or more drugs are commonly used (such as general anesthetics, hypnotics, sedatives, paralytics, narcotics, and analgesics), each of which serves a specific purpose in creating a safe anesthetic.
Anesthesia is unique, in that it doesn’t offer any particular benefit, rather it allows others to do things that might be beneficial. The best anesthetic, therefore is the one with the lowest risk to the patient that still achieves the endpoints required to complete the procedure. The first stage of an anesthetic is the pre-operative risk assessment made up of the medical history, physical examination and lab tests. Diagnosing a person’s pre-operative physical status allows the clinician to minimize anesthetic risks. A well completed medical history will arrive at the correct diagnosis 56% of the time which increases to 73% with a physical examination. Lab tests help in diagnosis but only in 3% of cases, underscoring the need for a full history and physical examination prior to anesthetics. Incorrect pre-operative assessments or preparations are the root cause of 11% of all adverse anesthetic events.
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