Repeat injections (Fig 130.47 B ) in this fashion Continue injections until complete infiltration of the circumference of the wound has been achieved (Fig 130.47 C ) Allow minutes for anesthesia If the field block is used to prevent distortion of the wound margins, then anesthetic is infiltrated in a diamond-shaped fashion around the wound The needle is inserted at the proximal end of the wound, and lidocaine is injected slowly as the needle is advanced The needle is then withdrawn and redirected approximately 90 degrees, and infiltration is continued The needle is then reinserted at the other end of the wound and the process repeated until the diamond-shaped ring of lidocaine is complete (Fig 130.47 D ) Anesthesia should be achieved by to 10 minutes PERIPHERAL NERVE BLOCKS Complications Infection Bleeding Intravascular, intraneural injections Equipment Antiseptic solution 3- to 5-mL syringe 1% or 2% lidocaine (may be alkalinized with 1-mL NaHCO3 to 10-mL lidocaine) or 0.25% bupivacaine 27- to 30-gauge 1- to 1.5-in needle Digital and Metacarpal Nerve Block Indications Anesthesia of fingers and toes for surgical procedures (i.e., drainage of a felon or paronychia, removal of a foreign body, or laceration repair) including the proximal digit Caution Do not use a vasoconstrictor such as epinephrine with the anesthetic agent Procedure Identify the area that requires anesthesia If it includes more than the distal twothirds to three-fourths of the finger or toe, use the metacarpal nerve block For more proximal procedures, use the proximal digital nerve block, discussed below