The purpose of this study is to determine if the transthecal metacarpal block is superior to
the traditional digital block for regional digital anesthesia in children.
Background: Finger injuries and infections are common presenting problems in the pediatric
emergency department. A traditional digital block, requiring at least two injections of
anesthetic, is the traditional method of regional anesthesia for many finger procedures.
Digital blocks can sometimes be difficult to administer and assess for effectiveness
especially in children. A newer procedure, the transthecal metacarpal block, may be easier
to administer, and more effective with one injection.
Objective: To determine if the transthecal metacarpal block (MCB) provides superior digit
anesthesia in children requiring painful finger procedures as compared to the traditional
digital block (TDB).
Methods: A randomized clinical trial comparing the MCB to the TDB will be conducted in an
urban, tertiary care pediatric emergency department. Children <18 years of age, presenting
to the emergency department with a finger injury or infection, which requires regional
anesthesia for repair will be screened for eligibility. Eligible patients, with appropriate
consent will be randomized to receive either the MCB or TDB with 1% Lidocaine. The primary
outcome, success of the block will be assessed using pinprick testing after a standardized
wait time. Secondary outcomes including pain with the block and repair, repairing physician
satisfaction, and short-term complications will also be assessed.
Implications: Finding successful methods of anesthesia and pain control are paramount in the
pediatric emergency department. In addition, using a type of digital block which is easy to
administer, successful, and requires only one injection would give physicians confidence to
treat finger injuries in children with regional anesthesia and possibly avoid procedural
sedation in some cases. To date, no studies have been published on the efficacy of digital
blocks in children. This study will also serve to give baseline success rates for both types
of digital blocks.
- Age <18 years
- Greater than 10 kg in weight
- Have finger injuries or infections that will require digital regional anesthesia
- Require only local anesthesia for the repair
- English speaking
- Have previous participation in this study
- Need procedural sedation at the onset of the repair
- Have allergy to lidocaine or amide-type local anesthetics
- Have infection at the sites of block injection
- Have known coagulopathy
Elizabeth R Alpern, MD, MSCE
The Children's Hospital of Philadelphia, Division of Emergency Medicine