Anesthesia is the use of medications to block the pain of a medical procedure. The medications that block this pain are called anesthetics. Different forms of anesthesia are used to prepare patients for different types of procedures.
Local anesthesia is used for minor procedures such as sutures or skin biopsies. A physician uses local anesthetic to numb a small area of tissue without affecting surrounding areas. Local anesthetic drugs can be applied on the skin's surface or injected at the site of the procedure. The numbness typically wears off within a few hours.
Regional anesthesia is used for more extensive procedures that involve larger areas of the body, such as a knee or hand. Regional anesthetic drugs can block sensation in an entire limb. They do not cause the patient to lose consciousness. Regional anesthetic is typically given through a catheter.
Conscious sedation is a form of anesthesia that relaxes the patient and dulls painful sensations. This type of anesthetic can be taken as a pill, or it can be injected or inhaled. Conscious sedation is often used during procedures such as endoscopy and plastic surgery. A patient who is given this type of anesthetic remains awake and is alert enough to respond to questions. Typically the patient will not remember the procedure.
General anesthesia results in a complete loss of consciousness. General anesthesia is used for major surgery or when other types of anesthesia are not appropriate. General anesthesia drugs may be inhaled or injected. They affect the entire body. The patient's vital signs must be closely monitored until the anesthesia wears off. A patient who is under the influence of general anesthesia usually requires breathing assistance.
The type of anesthesia that is most appropriate for a particular procedure depends on the patient's need. For complex procedures, an anesthesiologist will help make this decision. Patients will be asked about their physical and mental health. They will be asked about food and drug allergies and medication usage. They will also be asked about previous experiences with anesthesia.
Anesthesia can have profound effects on the body. Modern techniques have minimized its risks and its side affects. Any time anesthesia is used, the patient's health is closely monitored.