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طبعا دي حاجه بنشوفها كل يوم و في اي مكان و مش في كل مره هيكون في وجود دكتور تخدي

فهنعرض كده كام طريقه انشاء الله تفيد الجميع
Selection of Anesthetic Agent
The most commonly used local anesthetic agents are lidocaine (1% or 2%) solution and bupivacaine (0.25% or 0.5%) solution. Lidocaine is effective quickly but lasts 1.5 to 3 hours. Bupivacaine is effective over 15 to 30 minutes, but lasts 3 to 10 hours. A 50-50 solution of the two agents is effective in combining the benefits of both agents. Solutions with epinephrine should not be used in blocks around the fingers and hand because of its vasoconstrictive effect. The maximum dose of anesthetic agents is lower when given without epinephrine. The maximum dose of lidocaine is 4.5 mg/kg. For adults, the maximum total dose should not exceed 300 mg. The maximum dose of bupivacaine is 2.5 mg/kg. The maximum total dose of bupivacaine should not exceed 175 mg. The addition of 1 mL of sodium bicarbonate solution per 10 mL of anesthetic alkalinizes the solution and decreases discomfort during injection. As with any injection, it is important to aspirate before injecting to avoid an intravascular injection of the agent. Early symptoms of toxicity from an intravascular injection include headache, ringing in the ears, numbness in the tongue and mouth, twitching of facial muscles, and restlessness. As the systemic levels of the agent increase, convulsions can result, followed by respiratory arrest and arrhythmias.


Types of Blocks
Field Blocks
Direct infiltration into the wound edges is useful for many dorsal wounds and some palmar wounds where exploration of deep structures is not anticipated. It is also commonly used for procedures such as first dorsal compartment and trigger finger releases. When done with a long-acting anesthetic agent, it provides postoperative analgesia after short-acting anesthetics such as Bier blocks or general anesthesia. The technique is simple and may be converted to another type of block if insufficient. The disadvantage is that it makes the soft tissues edematous and sometimes hemorrhagic, thereby further injuring the soft tissue and distorting the anatomy.
When doing the block, a 25-gauge, 1½-in. needle is inserted at one end of wound and advanced parallel along one side of the incision. The anesthetic is injected subcutaneously until the wound edges are seen to swell. The deep spaces may be injected similarly if required.


Digital Blocks
Digital blocks are the preferred type of anesthesia for procedures done distal to the PIP joint. Caution should be used when giving digital blocks after injury to the digital artery that may require revascularization because the digital nerves and arteries run together. Digital blocks should also not be given when there is an infection around the MP joint.
A 25-gauge, 1½-in. needle is inserted distally in the web space where the skin innervation is less dense than in the palm (Fig. 1). The needle is advanced under the dorsal skin to the MP joint and 1 mL of anesthetic is injected into the subcutaneous space. The needle is withdrawn half way and directed palmarly between the MP joints. The needle is advanced until it is almost subcutaneous. Two to three milliliters are injected palmarly. The procedure is then repeated on the other side of the digit.
In the thumb, the two digital nerves are more palmar and closer together than in the digit. The ulnar digital nerve lies just palmar to the first web and the radial digital nerve lies just radial to the midline. Both nerves can be blocked by inserting the needle from ulnar to radial into the first web space at the MP joint. Two to three milliliters of anesthetic are injected transversely along the MP crease. Dorsal injections are given via sites at the radial and ulnar borders of the MP joint. Care should be taken to not give a “ring block,” or circumferential injection at the MP joint. This block may tightly compress the tissues and compromise vascularity of the digit. As with any block in the hand, no effort is made to elicit paresthesias during the injection. The needle should be withdrawn and replaced in order to avoid injection into the nerve if paresthesias are elicited.



Wrist Block
Four nerves may be blocked at the wrist. These are the median nerve, ulnar nerve, dorsal sensory branch of the radial nerve, and dorsal sensory branch of the ulnar nerve. The nerves to be blocked are dependent on the region of the hand that must be anesthetized. The thumb, index, middle, and radial border of the ring finger are innervated by the median nerve on the palmar surface and the dorsal sensory branch of the radial nerve on the dorsal surface. The small finger and the ulnar border of the ring finger are innervated by the ulnar nerve on the palmar surface and the dorsal sensory branch of the ulnar nerve on the dorsal surface. The median and ulnar nerves mainly innervate deep structures. In general, 5 mL of anesthetic are given at each site. Prior to injection, the patient should be told about the possibility of paresthesias if the nerve is punctured. The patient is told to tell the surgeon if any electric shocks are experienced. The anesthetic agent is injected only after the patient states no paresthesias are present. Once the injection begins, the needle should not be repositioned, thereby avoiding an intraneural injection of an anesthetized nerve.





The median nerve is located underneath the palmaris longus tendon. The injection is given ulnar to the palmaris longus tendon (Fig. 2A). A line is drawn from the ulnar border of the middle finger to the wrist crease if the patient does not have a palmaris longus tendon. With the wrist slightly extended, the needle is inserted just proximal to the wrist flexion crease and directed distally at a 30-degree

angle and slightly radially. Two distinct regions of resistance are felt as the needle is inserted. The first is on entering the skin and the second is piercing the antebrachial fascia. Once the patient states that no paresthesias are present, the solution is injected. A slight bulging in the palm, distal to the carpal tunnel, indicates proper placement of the agent.



انقر على هذا الشريط لمشاهدة الصوره بحجمها الطبيعي.

The ulnar nerve lays ulnar to the ulnar artery in Guyon's canal. The neurovascular structures lie radial to the pisiform and ulnar to the hook of the hamate. The ulnar nerve is anesthetized by placing the needle at the radial border of the pisiform (Fig. 2B). The needle is inserted until it clears the radial edge of the pisiform and passes deep into Guyon's canal. Alternatively, the needle may be placed just radial to the flexor carpi ulnaris tendon at the wrist flexion creases. The solution is injected once the patient states that no paresthesias are present.
The dorsal sensory branch of the radial nerve exits from between the brachioradialis and extensor carpi radialis longus 5 to 8 cm proximal to the radial styloid. It divides into multiple branches distal to the radial styloid. The injection is placed 1 cm proximal to the radial styloid, radial to the radial artery (Fig. 2C). The needle is advanced dorsally to Lister's tubercle and 5 mL of anesthetic is subcutaneously administered throughout this region once the patient states that no paresthesias are present. Care is taken to aspirate before injecting to avoid an intravascular injection.
The dorsal sensory branch of the ulnar nerve passes from palmar to dorsal in the region of the ulnar styloid. The injection is placed at the level of the ulnar styloid beginning at the flexor carpi ulnaris, extending dorsally to the distal radioulnar joint (Fig. 2D). Five milliliters of anesthetic are administered
subcutaneously throughout the region.


Other Blocks
The Bier block and the infraclavicular (axillary) block are two other commonly used blocks for the arm. Both are usually administered in a setting with resuscitation equipment available, preferably in a patient with an empty stomach because each of these blocks may have a complication with anesthetic toxicity. Many surgeons prefer that an anesthesiologist in an operating room perform these blocks.
A Bier block is an intravascular injection of an exsanguinated arm. Cast padding is applied to the arm and two 18- or 24-in. tourniquets are applied. An IV is inserted into a dorsal hand vein. The arm is exsanguinated by tightly wrapping it with an elastic bandage. Good exsanguination is the key to the procedure, obtaining both uniform anesthesia and a bloodless field. The distal tourniquet is first inflated to 250 or 100 mm Hg above the systolic blood pressure in hypertensive patients. The proximal tourniquet is then inflated and the distal cuff is released. Lidocaine 0.5% without preservatives is given as 3 mg/kg. The block is usually effective within 10 minutes. If the patient experiences tourniquet pain after 20 to 30 minutes, the distal cuff is inflated and the proximal cuff is then
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released, giving another 20 to 30 minutes of operative time. The tourniquet may be released 30 minutes after injection of the anesthetic.
The main advantage of Bier block anesthesia is that it is technically easy. Following release of the block, motor control returns in 10 to 15 minutes, allowing the surgeon to assess the results of a tenolysis. The disadvantages include tourniquet pain, which limits the usefulness of this block in procedures lasting more than 1 hour. The anesthetic effect lasts 5 to 10 minutes after release of the tourniquet, giving insufficient time for obtaining hemostasis and closing skin in some procedures. The block should not be used when infection or malignant tumors are present, as exsanguination of these limbs may spread the condition proximally. The major complication is early loss of tourniquet pressure, which is associated with systemic release of the agent and potential toxicity.
Infraclavicular blocks produce an effective sensory and motor blockade. With the use of long-acting anesthetics, these blocks also provide effective postoperative pain relief. The anesthetic agent is placed in the fascial compartment containing the peripheral nerves and axillary artery and vein. Considerable experience is required to adequately place this block and avoid an intravascular injection. The block is performed in a setting with resuscitation equipment available.

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