The Local anesthesia is mainly used when it is only a question of anesthetizing the skin over a small area (for example when visiting the dentist). A fundamental distinction is made between surface anesthesia and infiltration anesthesia and some other sub-forms. The aim is always to switch off the pain in a specific part of the body for a certain period of time, while maintaining consciousness and motor skills in contrast to general anesthesia.
Local anesthesia is mainly used when it is only a question of anesthetizing the skin over a small area (for example when visiting the dentist).
In the Local anesthesia (also local anesthesia called) is an anesthetic in which the sensation of pain is temporarily switched off in a precisely defined area of the skin. The agents used are called local anesthetics. These work at the branches of the nerve endings directly in the subcutaneous tissue and avoid the transmission of pain impulses to the brain.
These nerve inhibitions are reversible and subside after a while. This allows medical interventions to be carried out without pain, while the ability to move and consciousness is not switched off.
The Local anesthesia is a branch of regional anesthesia, whereby there are two basic forms: infiltration anesthesia and surface anesthesia.
With surface anesthesia, the active ingredients are injected directly into the skin of the area where the operation is to take place. Typical examples are dental treatment or the removal of a mole. In infiltration anesthesia, sprays or drops with cotton swabs can be applied to the cornea, mucous membranes or conjunctiva.
Typical of these procedures are gastroscopy, awake intubations (inserting a ventilation tube into the mouth and throat) and eye examinations. Furthermore, a distinction is also made between conduction anesthesia, which includes entire body regions supplied by specific nerves. There is also intravenous regional anesthesia, in which a cuff is used to congest an extremity and the anesthetic is then injected into a vein.
There are also central conduction anesthesia (spinal anesthesia and epidural anesthesia), which work in such a way that spinal nerves close to the spinal cord are blocked and several parts of the body are made pain-free for a certain period of time.
There are local anesthetics with a shorter or longer effect. It is possible to add adrenaline to the anesthetic to extend the duration of its action. This is because the adrenaline constricts the blood vessels, thus reducing the blood flow to the tissue so that the local anesthetics are effective for longer. It must be taken into account that, for example, adrenaline must not be used on toes or fingers, because otherwise the tissue can die.
With the use of local anesthetics, treatments can be carried out painlessly that would otherwise be associated with very unpleasant side effects for the patient. The advantage is that consciousness and motor skills are retained, so the patient can “fully notice” everything. For this reason, local anesthetics are less risky than anesthetics that turn off consciousness and motor skills.
In contrast to general anesthesia, brain and lung function, the acid-base balance and the metabolism are hardly impaired with local anesthesia. This allows treatment with local anesthetics even if the patient is in poor general condition and general anesthesia is too risky. If possible, local anesthetics are used predominantly, while general anesthesia is only used when the treatment cannot be carried out otherwise.
However, it can be a side effect of Local anesthetics cause various allergic reactions. These are also the most common undesirable side effects of these anesthetic procedures. Theoretically, poisoning (intoxication) can also occur in tissue with good blood circulation, in which the local anesthetic is quickly removed.
This goes hand in hand with nervousness, dizziness and seizures. A drop in blood pressure and cardiac arrhythmia can also result. The latter side effects are very rare, however, as usually only very small areas of the skin are numbed. This eliminates the need for the amount of local anesthetic that could cause poisoning.
In general, however, one can say that local anesthetics are far less risky than general anesthesia, so that in case of doubt these procedures are more likely to be used.