Blockade of a brachial plexus

Description:

Blockade performance technique. The patient lies on spin, the head has to be a poyovernuta on 30-45 ° in the party, opposite to the place of blockade. The middle of a clavicle is identified. Displacing грудино - a clavicular and mastoidal and front scalene forward and up, palpate a subclavial artery. In an interladder interval pulse is well felt. Use a needle with the blunted edges of a cut of 22-23 G in size and 4 cm long. The point in Coca is a little above the upper edge klyuchiyoets (approximately on finger width), enter a needle into an interladder interval directly towards the place of the maximum pulsation of a subclavial artery before emergence of paresthesias. If there are no paresthesias, then the needle is advanced to a soyoprikosnoveniye with the first edge. At a needle peremeshcheyoniya on the upper surface of an edge often there are paresthesias. If when using a needle 4 cm long during aspiration test bright red blood or air are received or it was not succeeded to reach an edge, then it is necessary to take a needle and again to estimate anatomic reference points. At aspiration of air it is necessary to execute a thorax X-ray analysis. At hit in an artery it is necessary to remove slowly a needle before the blood aspiration termination then it is possible to enter anesthetic, without waiting for paresthesias. At supraclavicular access enter 25-30 ml of local anesthetic.

  Complications. The most widespread complications are pheumothorax and гемото­ракс. Frequency of pheumothorax makes 1-6% though clinically significant (more than 20% of volume of a hemothorax) or a tension pneumothorax meet seldom. Pheumothorax can vozniyokat is delayed therefore expediency of an isyopolzovaniye of supraclavicular access at ambulayotorny interventions is represented somniyotelny. Emergence of a syndrome of Horner or blockade of a phrenic nerve is possible.

Subclavial access
    Technique of performance of blockade (fig. 4). The patient is on spin, the head is located in neutral situation. Skin is infiltrirut 2,5 cm below by the middle of a clavicle. Use a spinal needle of 22 G in size and 9 cm long. Attach the syringe to a needle and enter it in the lateral direction at an angle 45 ° to skin towards a head of a humeral bone. As an additional reference point it is palpatorno possible to define a pulsation of a subclavial artery in this area. Send to Eagle on a tangent to the surface of a breast in order to avoid a pleura puncture. At a depth of 5-7 cm there are paresthesias that serves as a signal for introduction of 20-25 ml of solution of local anesthetic. Apply also an elektroyostimulyation. Aspiration of air serves pokazayoniy to a thorax X-ray analysis.

    Complications. There is a risk of a pnevmotoyoraks, hemothorax and chylous hydrothorax (at levostoyoronny access), and it is higher, than at an ispolyyozovaniye of supraclavicular access. Nevertheless, neyokotory anesthesiologists constantly use subclavial access.

Axillary blockade
    Technically it is rather simple to carry out such blockade, it seldom causes complications. From all accesses to a brachial plexus podmyyoshechny blockade provides the most polnotsenyony anesthesia of branches C7-T1 (an elbow nerve).

    Technique of performance of blockade (fig. 5). For performance of blockade it is possible to use lyuyoby of below-mentioned techniques, but at the choice it is necessary to define, first of all, pulse on an axillary artery. The patient lies on spin, the hand of an otyoveden in a shoulder joint and is bent in an elbow at an angle 90 °. The hand shall be higher than the level of a body because the shift of a humeral bone complicates a pulse palpation on a pleyochevy artery forward. The medial cutaneous nerve of a shoulder leaves a fascial case at once below klyuchiyoets and therefore it cannot be blocked at axillary blockade regardless of an ispolzuyeyomy technique. Therefore, for blockade of this and intercostal and humeral nerve it is necessary to inyofiltrirovat anesthetic a hypodermic kletchatyoka in an artery projection that also allows to use a pneumatic tourniquet (see earlier). The anesthetic solution injection in thickness of a coronoid and humeral muscle provides blockade of a musculocutaneous nerve.

1. Chrezarterialny access. Define pulse on an axillary artery as it is possible proksimalny in an axillary pole, it is ideal — proksimalny from a crest of a big hillock of a humeral bone (the place of an attachment of a big pectoral muscle). Use a needle with the blunted edges of a cut of 25 G in size both 2 cm long or 22 G in size and to Eagle 4 cm long enter in the direction of a pulsation point. A signal to the termination of introduction buyodt receiving bright red blood at aspiration. After that the needle is carefully advanced or back until stops postupyoleny blood at aspiration. It is reasonable to use a technique of "a motionless needle" (see rayony). Anesthetic is entered either in front, or behind from an artery, and sometimes in both places: the choice opredelyayotsya by the venue of operation and opinion of an anesyoteziolog concerning a role fascial a pereyogorodok. If surgical intervention zatyoragivat the area which receives an innervation more than from one trunk of a texture, then anesthesiologists who hold the opinion on an important role of fascial partitions prefer to enter anesthetic in both points — in front and szayod from an artery. The general dose of anesthetic makes 40 ml, pressure upon fabrics distalny places of an injekyotion promotes proximal distribution of anesthetic in a fascial case and to a vovleyocheniye in the block of proximal branches, for example a musculocutaneous nerve.
2. Verification of provision of a needle on a zone of pareyosteziya. In certain cases the anesthesiologist nameyorenno causes paresthesias, in other cases they arise in passing, when performing blockade by other technique. Knowing about the venue of predstoyoyashchy operation and representing extremity innervation zones, the anesthesiologist tries to receive pareyosteziya in the zone interesting him. For example, for treatment of a fracture of the V metacarpal bone it is necessary to doyobitsya paresthesias in a zone of an innervation of an elbow nerve for what the needle is directed slightly below by pulsation points on an axillary artery (fig. 17-8). In the beginning the fascia puncture then бы­стро there is paresthesia is felt. It is reasonable to prekrayotit advance of a needle at once after there are paresthesias. As it was noted earlier, use of needles with the blunted edges of a cut sniyozhat probability of an intraneural injection. Neyokotory strengthening of paresthesias during an injection is a normal phenomenon and confirms the correct provision of a needle. Burning, muchitelyyony pain testifies to an intraneural vveyodeniye of anesthetic therefore in order to avoid a povrezhyodeniye of a nerve it is necessary to stop immediately an injyoektion and to change the provision of a needle.

    Considering existence of partitions in a fascial case, some anesthesiologists aim to get paresthesias in a zone of an innervation of elbow, median and beam nerves for what enter anesthetic solution in several points. Pressing on soft tissues distalny places of an injection, enter 40 ml of solution of anesthetic. At the same time total quantity of the injected drug remains to constants regardless of that, vvoyodit anesthetic in one point or in several.
3. Futlyarny perivascular blockade. To Eagle with the blunted edges of a cut the surfaces of skin in the direction over tochyoky enter perpendikuyolyarno pulsations to a fascia. As soon as the needle prokoyolt a fascia, the syringe is disconnected and on a peredatochyony pulsation of a needle judged proximity of an artery. The needle is inclined almost parallel to skin and proyodvigat on 1-2 cm. Pressing on soft tkayon distalny places of an injection, enter 40 ml of a rayostvor of anesthetic.
4. Electrostimulation of a nerve. As in case of an opyoredeleniye of localization of a needle on a paresthesia zone, the provision of a needle of rather axillary aryoteriya depends on the venue of operation. Nayoprimer, at intervention on a sinew of a razgibayotel of a thumb it is necessary to block a beam nerve therefore the tip of a needle has to raspoyolagatsya behind from an axillary artery. The Pravilyyony provision of a needle is confirmed at indutsiyorovanny by electrostimulation extension of a bolyyoshy finger. For more exact definition of a poloyozheniye of a nerve it is necessary to delay a needle to an ischeznoveyoniya of motor reaction, and then to enter again before its emergence. Besides, a variation the napryazheyoniya allows to reduce current. If muscular contraction arises at electrostimulation with a current of 1 мА, then the probability непосредственно­го contact of a needle with a nerve is high, and at current 0,5 мА it makes nearly 100%.

    At the electrostimulation which is carried out against the background of an anesthetic solution injection kratyokovremenny strengthening of muscular contraction because anesthetic, being, salt of a salt kisyolota, is a conductor of current is observed and increases nervous impulse up to the beginning of development of a bloyokada. After short-term strengthening proiskhoyodit bystry decrease (fading) in activity. In the absence of strengthening and fading of a muscular aktivyonost at electrostimulation against the background of administration of anesthetic it is necessary to stop an injection and to izmeyonit the provision of a needle. Against the background of a distal prelum of fabrics enter 40 ml of solution of anesthetic.

Complications. The risk of an intra arterial injection of anesthetic is higher when using chrezarterialny access. Identification of paresteyoziya, especially in several places, can povyyosit risk of postoperative neuropathy though this statement is very controversial. The infection and a gemayotoma arise very seldom.