Local anesthesia is the second major field of anesthesia after general anesthesia. It is used for local (locally limited) analgesia without affecting consciousness. Nerve endings or pathways are reversibly (non-permanently) anesthetized for a limited period of time using so-called local anesthetics. The beginnings of local anesthesia date back to 1884, the year in which Carl Koller, an ophthalmologist working in Vienna, first used cocaine to anesthetize the eye. The substance cocaine is obtained from the leaves of the South American coca bush. Even before Koller, the anesthetic effect of cocaine was described. However, there were frequent incidents of cocaine intoxication (poisoning) during its use in 1885, so that further development of local anesthesia was mandatory. Today, the different variants of local anesthesia allow a variety of small and large operations. This article has an introductory function and highlights the composition of the overall topic into various subtopics. Local anesthesia is divided into the following subtopics:
- Surface anesthesia
- Infiltration anesthesia
- Tumescent anesthesia
Indications (areas of application)
The areas of application of local anesthesia are very extensive, so that an exact enumeration would lead too far in this framework. However, the indications of the individual subfields of local anesthesia, subsequent in the individual articles on it, are discussed comprehensively.
Before local anesthesia
As a rule, no special precautions need to be taken before local anesthesia is performed. However, an allergy to the local anesthetics used should be ruled out in advance. Depending on the local anesthetic procedure, individual measures may be required (see the related articles below). In addition, different preparations are made depending on the operation for which local anesthesia is necessary.
The procedure
The following is a brief description of the subspecialties of local anesthesia; if you would like to learn more about them, please read the full articles:
- Surface anesthesia – It is used for “superficial” anesthesia of pain. Here, mucosal anesthesia is distinguished from topical local anesthesia of the skin. The local anesthetic is usually administered as a spray in the case of mucosal anesthesia, while topical local anesthesia is performed with the help of a cream.
- Infiltration anesthesia – Infiltration anesthesia is the injection of local anesthetics intradermally (into the skin), subcutaneously (into the subcutaneous fat tissue), or intramuscularly (into the muscles) to temporarily interrupt the conduction of pain.
- Tumescent anesthesia – This form of infiltration anesthesia is used for cosmetic surgery procedures, such as liposuction (fat removal). For this purpose, a large volume of fluid mixed with a local anesthetic is injected into the subcutaneous fat tissue, which facilitates the actual liposuction.