A nerve block "turns off" the transmission of pain in the peripheral nervous system - in the nerves on which it was performed. It is worth finding out how such anesthesia works, when it can be performed and what the procedure looks like.
Nerve blockis one type of local anesthetic and is performed with similar medications as for infiltration anesthesia at the dentist or for suturing.
Peripheral block is safe anesthesia, but requires technical skills, experience and knowledge of anatomy from the anesthesiologist.
During the procedure, the patient remains conscious, but feeling and mobility in the anesthetized part of the body is reduced.
Interlocks are reserved for a fairly narrow group of treatments, most often small operations in the field of limbs (e.g. wrist, foot), neck or in dentistry.
The mechanism of their action is based on the inhibition of the transport of ions (mainly sodium) across the cell membrane of neurons, which results in the stabilization of both the cell membrane and its potential. T
This mechanism of action causes that local anesthetics used in blockades to reversibly inhibit the generation and transmission of impulses in peripheral nerves. Anesthesia lasts as long as the drug administered is not broken down by the body.
The principle of the blockade is the inhibition of conduction through nerve structures (large nerves or nerve plexuses), supplying individual parts of the body, or larger areas.
The basic feature of such anesthesia is their complete reversibility and keeping the patient conscious, the latter feature distinguishes them from general anesthesia - "anesthesia".
Therefore, it is less burdensome for the respiratory and cardiovascular systems, and therefore it can be used in people with many other diseases who have an increased risk associated with general anesthesia.
Epidural anesthesia, commonly called "spine" anesthesia, is sometimes considered a special type of blockade, in which the transmission of pain is inhibited at the level of the nerve entry into the spinal canal.
Nerve blocks are most often performed on specific nerves or plexuses (these are connections and branches of neurons), e.g. the brachial plexus - it supplies the entire upper limb, so such anesthesia covers the entire hand.
Another area where such anesthesia can be performed is the areawrist (radial, ulnar and median nerves), or ankles (tibial and peroneal nerves), then it covers the hand and foot, respectively, the cervical plexus to numb the neck and upper chest.
Of course, blockades can also be used in other places, as long as the location of the nerve supplying this area is determined.
The doctor who performs such anesthesia determines the course of the nerve on the basis of anatomical relations, i.e. based on his knowledge, he determines the place where a specific nerve is most likely to run.
Special stimulators or ultrasound are used less frequently for this purpose.
Due to the necessity of precise assessment of the injection site, it is sometimes a long procedure, because before starting the surgery, the anaesthesiologist must be sure that the anesthesia is working properly.
Once the site is in the right place, the anesthetic is usually injected with a syringe quite deep into the tissues surrounding the nerve or plexus, or into the structure itself.
The drug then penetrates deep into these structures, which takes about 30 minutes, after which the anesthetic begins to work.
It causes the inhibition of pain sensation, but unfortunately sometimes also temporary exclusion from the functioning of the anesthetized part of the body.
This is because nerves have both sensory fibers for the skin and motor fibers for the muscles, and during anesthesia we act on the entire nerve.
Blocking the action of these fibers causes not only the "switch off" of the feeling, but also the action of the muscles.
Of course, such analgesia and disabling the mobility of a given limb are completely reversible, these functions return after a different length of time depending on the anatomical area, what drug was used and the general condition of the patient.
First, the motor function returns, followed by the feeling and sensation of pain, thanks to which the blockade also ensures the relief of pain after the procedure.
Nerve block: when is it used?
Interlocks are used in many different situations, for example :
- minor surgery, usually on the limbs
- persistent pain in the nerve or plexus, the cause of which cannot be treated, so-called chronic pain
- as an addition to general anesthesia if the surgery is extensive and painful
- after surgery, if pain persists after surgery, it applies to a well-defined anatomical location, and drugs administered orally are not fully effective or are contraindicated
In addition to the relief of pain, blockade also inhibits the stateinflammation, vascular spasms and slight muscle relaxation in the area of drug administration.
Blockades are safe procedures, but they should be performed by an experienced physician, usually an anesthesiologist. Complications are rare and harmless, e.g.
- hematoma at the injection site
- puncture of structures adjacent to the nerve
- insufficient anesthesia - then a different method is used or the blockade is repeated to ensure maximum comfort for the patient.
Nerve damage or failure to regain full fitness after blockades are extremely rare.
When it is not possible to use interlocks?
This type of anesthesia may not always be used, contraindications include, for example:
- skin infection at the site of drug administration, in which case there is a risk of transferring it under the skin and causing muscle or nerve infection, for a similar reason a contraindication is a systemic bacterial infection
- coagulation disorders that can cause bleeding after needle puncture
- some neurological diseases, in this case the risk is associated with the risk of worsening the neurological condition of the sick person
Continuous Nerve Block
Sometimes the so-called continuous blockade is also used, it consists in placing the end of a thin catheter (tube) in the area of the structure to be anesthetized and connecting a pump containing the drug to it.
This results in a continuous flow of analgesic agent and uninterrupted blockage for as long as the drug is administered. It is a long-term solution, usually in advanced neoplastic diseases
ImportantThere are many methods of anesthesia (analgesia), they allow you to turn off the feeling of pain in a specific location or throughout the body. The choice of the type of anesthesia depends on the he alth condition, the possibility of complications and the purpose of its use (temporarily or for surgery).
Local anesthesia is widely used in medicine, the most common in this context is infiltration anesthesia, i.e. the one used, for example, at the dentist's or when placing sutures. Local anesthetics start working after a few minutes, maintaining anesthesia for up to 12 hours depending on the type of substance administered.
A very important aspect of local anesthesia is its safety - side effects practically do not happen, and if they do occur, they are harmless. What is also important, for such analgesia you do not need preparation, and you do not need to be on an empty stomach (unless the procedure itself requires it).
Also read:
- Anesthesia at the dentist's, i.e. treatment of teeth without pain
- Hypertension and epidural [Expert advice]
- Block anesthesia with adrenaline [Expert advice]