Local anesthesia: types, methods, drugs

Advantages and disadvantages

For simple surgical interventions, local anesthesia is indispensable; it has advantages over other types of sensitivity suppression. The drug that is used, an anesthetic solution, acts strictly at the injection site, which helps to avoid severe complications and adverse reactions.

The blockade of pain sensitivity develops on average in 10-15 minutes. The effect lasts for an hour or more, so local anesthesia can reduce pain in the area of ​​the postoperative wound. The patient’s consciousness does not suffer from the action of the local anesthetic, so after the manipulation he can leave the clinic and not be in the ward.

But local anesthesia has its drawbacks. Just a few years ago, it was widely used for operations on superficial tissues and extremities; methods for intravenous administration of drugs with simultaneous application of a tourniquet were developed. Intraosseous anesthesia was widely used. But due to the large number of adverse reactions and complications, these methods began to be used less frequently. And after receiving high-quality drugs for anesthesia, dangerous methods of pain relief were practically abandoned.

The disadvantage of the local method is its limited scope of application. It is effective for anesthesia of mucous membranes, skin and superficial tissues, but is not used for operations on the abdominal and pelvic organs, neck and head.

The infiltration type of local anesthesia cannot be used when operating on malignant tumors due to the possibility of tumor cells entering beyond the wound into other tissues. This increases the risk of developing metastases.

Possible complications when using local anesthesia

The use of local anesthetics carries certain risks, which include several types of complications:

• damage to the central nervous system and conduction system of the heart;
• damage to spinal tissue, nerve roots and spinal cord membranes;
• suppuration at the site of anesthetic injection;
• allergic reactions.

In most cases, the listed problems arise when the anesthesia technique is violated, or when the anamnesis is not collected completely.

Types of local anesthesia

Several types of local anesthesia are used in surgical practice, but some of them already have historical significance. The main methods of pain relief are the following:

• superficial anesthesia - pain sensitivity is suppressed after the anesthetic comes into contact with the surface of the tissue, most often used to anesthetize the mucous membranes. The anesthetic solution is applied by lubrication or irrigation, the effect lasts for 10 minutes;
• infiltration anesthesia - anesthesia by impregnation, or infiltration of tissue layers with a local anesthetic. The technique allows you to control the depth and width of the drug injection, depending on the intended incision. The medicine is injected carefully first into the subcutaneous area until the lemon peel effect appears, then the needle is gradually moved inward and an additional dose of the drug is injected;
• anesthesia according to Vishnevsky is an improved version of the infiltration method. A weak anesthetic solution is injected layer by layer under high pressure. A tight creeping infiltrate forms in the tissues. It spreads through the interfascial spaces and disrupts the conduction of impulses along the nerves passing through them. After cutting the wound, the liquid gradually flows out of the wound, so there is no risk of its absorption into the systemic circulation and the development of toxic reactions;
• conduction anesthesia is the essence of the method in anesthetizing a specific area of ​​the body innervated by the nerve trunk. An anesthetic drug is injected into the tissue around the nerve; the technique is used for operations on the limbs;
• spinal anesthesia - the analgesic effect is achieved by injecting an anesthetic drug under the choroid of the spinal cord, the main place of drug administration is the lumbar region, and pain sensitivity in the pelvic organs and lower extremities disappears. But tactile sensitivity does not suffer;
• epidural anesthesia is a type of anesthesia in which a local anesthetic is injected into the space over the dura mater of the spinal cord, and a puncture is also performed in the lumbar region. Sensitivity is lost after 15-20 minutes, but the effect lasts for 3-4 hours. The use of this type of anesthesia allows you to resume activity early after surgery;
• bone anesthesia is a type of anesthesia in which an anesthetic solution is injected into spongy bone. Currently, it is practically not used; previously it was used for operations on the limbs.

Ubistezin

Ubistezin is a German drug that is produced. It contains the local anesthetic articaine and the hormone epinephrine (adrenaline), which has a vasoconstrictor effect. Vasoconstriction ensures a low degree of penetration of the drug into the blood and maximum effect at the site of use.

The drug has 2 release forms: with an epinephrine concentration of 1:200000 and 1:100000. The analgesic effect occurs within 1-3 minutes after administration. The duration of action is at least 75 minutes.

The drug is used only for anesthesia in dentistry (infiltration and conduction). It should not be administered intravenously or used in areas of inflammation.

Septanest

Septanest is an anesthetic that has been used in medical practice for quite some time. In addition to articaine and epinephrine, it contains auxiliary substances, which often cause complications of anesthesia in dentistry such as allergic reactions of patients. The drug is available in two dosage forms: with an epinephrine content of 1:100,000 and 1:200,000.

The effect of the drug appears after 1-3 minutes. Its duration is at least 45 minutes. It has good tissue tolerance and has a moderate vasoconstrictor effect.

Scandonest

What anesthesia in dentistry is suitable for patients with diabetes, thyroid diseases, an increased tendency to allergic reactions and patients with bronchial asthma? Scandonest is a drug that does not contain vasoconstrictor components or preservatives. Therefore, it is suitable for all patients at risk. For some, it is used with caution (during pregnancy, diseases of the liver, kidneys and cardiovascular system).

The anesthetic is produced on the basis of 3% mepivacaine. It provides fast, long-lasting and strong pain relief. Suitable for all types of local anesthesia.

Ultracaine

Ultracaine

– this is the best anesthesia in dentistry during pregnancy and for many diseases. It is based on articaine and is available in three forms: with a concentration of epinephrine 1:100000, 1:200000 and completely without epinephrine. The drug contains almost no preservatives. Lasts on average 2-3 hours. According to reviews from dentists and patients, ultracaine is the most potent among its analogues.

The cost of a carpule of any of the listed medications is approximately 30-50 rubles.
This article is for informational purposes only, please consult your doctor for details!

Preparations for local anesthesia

Local anesthetics are drugs from the group of neurotropic drugs that completely or partially block the flow of signals along nerve fibers from the site of painful manipulation or surgery to the central parts of the nervous system.

The peculiarity of the action of drugs is related to their spectrum of action. They suppress the transmission of signals along myelinated type A nerve fibers, which transmit feelings of pain, smell, and temperature. Tactile sensations are carried out through type B fibers, and anesthetics do not affect them. Therefore, when using local anesthesia, the patient does not feel pain, but feels the touch of the doctor and the surgical instrument.

Local anesthetic drugs are divided into 3 groups depending on the duration of action:

• short-acting - the effect lasts 30-50 minutes, these include Novocain;
• average duration - up to 90 minutes, these are drugs Lidocaine, Trimecaine, Ultracaine;
• long-acting – the effect lasts more than 90 minutes, typical for Bupivacaine.

Local anesthetic drugs affect the electrochemical processes of ion exchange in nerve endings. Medicines work effectively in an alkaline environment and tissues rich in lipids, which include nerves. But the analgesic effect decreases with severe tissue inflammation, which is associated with a transition of pH to the acidic side.

The effect of local anesthetics is enhanced by drugs that affect vascular tone. Therefore, they are often combined with adrenaline to prolong the effect. This allows you to reduce the dose of pain medication and avoid toxic reactions.

What is operated under local anesthesia in mammology?

The mammary glands are located superficially, they do not have muscles and large nerve trunks. Breast tissue is loosely located; in young women, glandular tissue predominates, which is replaced by fatty tissue with age. Therefore, for numerous manipulations and operations, local anesthesia can be used.

In mammology, anesthesia is used to perform invasive diagnostics, which include breast tissue biopsy. To do this, a local anesthetic is injected with a thin needle into the area of ​​the intended puncture. After 10-15 minutes, the doctor can take breast tissue for examination without fear of causing pain to the patient.

Local infiltration anesthesia in mammology is used for small, minimally invasive operations. A woman can undergo puncture of a breast cyst after preliminary infiltration anesthesia. A similar approach can be used when removing small benign breast tumors.

In men, anesthesia is used during surgery for type 1 gynecomastia, when the size of the gland is still small. Infiltration of tissues increases hydrostatic pressure in them, thanks to which the doctor can easily separate pathological tissues from healthy ones.

Is it painful to do local infiltration anesthesia?

When performing anesthesia, a standard disposable syringe with a thin needle is used. Whether local anesthesia is painful depends on your general pain threshold. The patient feels the moment of the first puncture of the skin and a slight feeling of fullness when the drug is administered. After the medication begins to act, sensitivity disappears. The doctor checks how effective the injection is by tapping the skin. In response, there is a feeling that the injection site has become woody.

After the end of anesthesia, sensitivity gradually increases, and a slight tingling sensation may appear. If anesthesia was performed for surgery, pain in the wound area begins to bother you, which can be reduced with the help of non-steroidal anti-inflammatory drugs.

Contraindications for local anesthesia

Local infiltration anesthesia is a relatively safe method of pain relief. But to reduce risks during and after surgery, it is necessary to take into account contraindications to the use of the method. The main ones are the following:

• allergy to anesthetic - if earlier during dental treatment under local anesthesia an allergy to an anesthetic appeared, then during breast surgery the effect will repeat, and may be more pronounced, up to anaphylactic shock;
• psychomotor agitation and mental illness, reaction to the administration of an anesthetic and the surgical procedure itself can cause unpredictable behavior of the patient;
• during operations on malignant tumors - when infiltration anesthesia does not allow compliance with the ablastic rule;
• during long operations that require the use of microsurgical equipment;
• during interventions on areas of the body with a pronounced vascular network, for example, on the neck.

If local anesthesia is contraindicated, general anesthesia is preferred.

Indications for local anesthesia

All methods of local anesthesia have the same list of indications, and are used if necessary to numb a specific area for a short time (up to an hour and a half). It is recommended to use them:

• for performing surgical non-abdominal interventions or small abdominal operations, the duration of which does not exceed 60-90 minutes;
• with intolerance to general anesthesia;
• if the patient is in a weakened state;
• if it is necessary to carry out diagnostic procedures against the background of severe pain;
• if the patient refuses general anesthesia;
• in elderly patients;
• when general anesthesia cannot be used.