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Do not use epinephrine in digital blocks: myth or truth?
B J Wilhelmi1, S J Blackwell, J H Miller
1Division of Plastic Surgery, University of Texas Medical Branch, Galveston, 77555-0724, USA.
Plastic and Reconstructive Surgery
|February 24, 2001
Summary
Epinephrine added to lidocaine for digital blocks safely prolonged anesthesia duration and reduced bleeding, decreasing tourniquet use. This suggests epinephrine is beneficial for digital anesthesia, enhancing patient outcomes and safety.
Area of Science:
- Anesthesiology
- Emergency Medicine
- Hand Surgery
Background:
- Digital block anesthesia is crucial for managing hand injuries.
- Lidocaine is a common anesthetic, but its short duration and lack of hemostasis can be limiting.
- Epinephrine's vasoconstrictive properties may improve digital block efficacy and safety.
Purpose of the Study:
- To evaluate the effectiveness of epinephrine in augmenting digital block anesthesia.
- To assess if epinephrine prolongs anesthesia duration and provides hemostasis.
- To determine the impact of epinephrine on the need for digital tourniquets and complication rates.
Main Methods:
- Prospective, randomized, double-blind study of 60 digital block procedures.
- Comparison of lidocaine with epinephrine versus plain lidocaine.
- Dorsal approach used for all anesthetic injections.
- Data collected on additional injections, tourniquet use, and complications.
Main Results:
- Fewer additional injections were needed with epinephrine (1/31) compared to plain lidocaine (5/29), though not statistically significant (p=0.098).
- Significantly less need for digital tourniquets when epinephrine was used (9/31) versus plain lidocaine (20/29) (p < 0.002).
- No complications occurred with epinephrine, compared to two with plain lidocaine (p=0.23).
Conclusions:
- Epinephrine augmentation of lidocaine for digital blocks is safe and effective.
- Epinephrine prolongs anesthetic duration, potentially reducing the need for repeat injections.
- The hemostatic effect of epinephrine significantly decreases the requirement for digital tourniquets, minimizing associated risks.
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