FINGER BLOCK: SINGLE SUBCUTANEOUS INJECTION IN THE MIDLINE PROXIMAL PHALANX WITH LIDOCAINE AND EPINEPHRINE (SIMPLE BLOCK)

SIMPLE is the acronym for single subcutaneous injection in the midline proximal phalanx with lidocaine and epinephrine.

When you inject 2 mL of buffered 1% lidocaine with 1:100,000 epinephrine in subcutaneous fat in the red injection point just under the skin without moving the needle, local anesthetic can be seen and palpated in the blue area in an unscarred patient. The two digital nerves always get numb. You numb the distal green area by nerve block, but this area has no epinephrine vasoconstriction and may bleed more because of the sympathectomy of the nerve block. This block can be helpful in frostbite of the fingertip.1

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  Only 2 mL is required for a good digital block. Use a 30-gauge needle on a 3-mL Luer-lock syringe.

  
  
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  There is level II evidence that patients prefer this block to the two dorsal injections block.2

  
  
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  There is level I evidence that needle penetration of the palmar skin is not more painful than needle penetration of web space skin.3

  
  
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  There is level II evidence that this block hurts less if you inject it over 60 seconds than if you inject it over 10 seconds.4

  
  
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  There is level II evidence that lidocaine without epinephrine digital blocks lasts 5 hours, whereas lidocaine with epinephrine blocks lasts 10 hours.5

  
  
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  There is level I evidence that the pain-relieving effect of bupivacaine blocks lasts 15 hours, whereas the annoying numbness to touch and pressure lasts more than 30 hours with these blocks.1

“SIMPLE” FINGER BLOCK WITH DORSAL BLOCK AUGMENTATION

When you inject 2 mL of buffered 1% lidocaine with 1:100,000 epinephrine in subcutaneous fat in the red injection point just under the dorsal skin without moving the needle, local anesthetic can be seen and palpated to diffuse in the blue area in an unscarred patient. In some patients, the SIMPLE block does not numb this dorsal area and it needs to be augmented with this second injection if you are applying a tourniquet at the base of the finger.

“SIMPLE” THUMB BLOCK (SEE ▶ Video 17.7)

When you inject 2 mL of buffered 1% lidocaine with 1:100,000 epinephrine in subcutaneous fat in the red injection point just under the skin without moving the needle, local anesthetic can be seen and palpated to diffuse in the blue area in an unscarred patient. The two digital nerves always get numb.

DORSAL THUMB PROXIMAL PHALANX BLOCK

When you inject 2 mL of buffered 1% lidocaine with 1:100,000 epinephrine in subcutaneous fat in the red injection point just under the skin without moving the needle, local anesthetic can be seen and palpated to diffuse in the blue area in an unscarred patient.