Digital Nerve Block
- Author: Dmitry Volfson, DO; Chief Editor: Meda Raghavendra (Raghu), MD more...
Digital nerve blocks are important tools for the emergency medicine clinician. Injuries or infections of the digits are extremely common. Adequate analgesia is essential to properly address the presenting condition and to minimize the patient's discomfort. Digital blocks are useful in many scenarios in which local infiltration of an anesthetic would require several injections into the already painful site of injury. Furthermore, local infiltration around the wound may create increased swelling, making the repair more difficult. Several techniques are available for performing digital blocks.
Each digit is innervated by 4 digital nerves. In the upper extremity, the digital nerves arise from the median, ulnar, and radial nerves. The 2 palmar digital nerves innervate the palmar aspect of the digit and the nail bed, whereas the dorsal nerves innervate the dorsum of the digit (see images below). The tibial and peroneal nerves branch off into the digital nerves of the lower extremities, which follow a pattern of distribution analogous to those of the upper extremity.
Digital blocks are indicated for any minor surgery or procedure of the digits. These include, but are not limited to, the following:
- Large irregular lacerations
See the list below:
- Compromised digit circulation
- Infected injection site
- Known allergy to anesthetic
See the list below:
- Avoid epinephrine use in the digits; a clamped Penrose drain can be used to limit bleeding.
- Limit the patient’s discomfort by using a smaller needle, injecting slowly, and using small amounts of anesthetics.
- Anesthesia of the great toe is more difficult to achieve and requires 3-sided/4-sided ring blocks.
- Use of sterile technique is essential to limit the risk of introducing infections (especially with the transthecal block).
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|Agent||Maximum Adult Dose (mg)/Procedure*||Onset (min)||Duration|
|*Administer by small incremental doses.|