Anesthesia

From ArticleWorld

Anaesthesia is the provision of sensation loss to all or part of the body for the purposes of pain control, surgery, wound or injury treatment. It can involve the loss of sensation to a small body area, a body region or to the entire body, which involves the patient becoming and remaining unconscious.

Types

General anesthetic refers to the giving of medications to eliminate pain and consciousness to an individual having surgery. Artificial ventilation is a part of this kind of anesthesia.

Local anesthesia usually involves injecting a local anesthetic, such as xylocaine, around an area of injury or an area needing excision. The effect of local anesthesia depends upon the type of medication injected.

Regional anesthesia involves blocking, with anesthetic medication, proximal large nerve that affects sensation to all of the nerves supplied by the larger nerve. Regional anesthesia is used in hand and foot surgery and is the basis for spinal anesthesia as well. Spinal anesthesia blocks all of the nerves below a certain level of the spinal cord that is given a localized anaesthetic.

Topical anesthesia has been traditionally associated with mucus membranes that take up topical medicines easily. Now there are skin-applied medications that provide brief anesthesia without an injection. Anesthesia sprays or the topical application of medicinal cocaine numbs the membranes of the upper respiratory tract.

Agents

Cocaine was the first identified local anesthetic in the 1800s. Newer local anesthetics are either amide- or ester-based. Ester anesthetics act quickly but are unstable during storage. Cocaine is an ester-based anesthetic. Allergic reactions are common with ester-based anesthetics. Amide-based anesthetics are more stable, have a lower onset of action and are less prone to allergic reactions.

Intravenous anesthetic agents include IV benzodiazepines, IV ketamine and etomidate. IV Fentanyl is an opioid agent commonly used in anesthesia.

Gaseous agents are used in the maintenance of general anesthesia. Halothane, isoflurane, desflurane and sevoflurane are all volatile anesthetics. In poorer countries, ether is still used as a general anesthetic. In dentistry, nitrous oxide is a commonly used anesthetic.

Providers

Anesthetists are nurses specially-trained to provide general anesthesia in surgery. Anesthesiologists are medical doctors who specialize in anesthesia and who also oversee the work of the anesthetists.