Buffered versus plain lidocaine for digital nerve blocks

Ann Emerg Med. 1993 Feb;22(2):216-9. doi: 10.1016/s0196-0644(05)80206-9.


Study objectives: To test whether buffered lidocaine is less painful to administer as a digital nerve block than plain lidocaine.

Design: Randomized, double-blind, prospective clinical trial.

Setting: University hospital emergency department.

Participants: Adults not allergic to lidocaine requiring a digital nerve block.

Interventions: Subjects received digital nerve blocks by injection of buffered lidocaine on one side and plain lidocaine on the other in a predetermined, randomized order. Pain of infiltration was assessed. Scores were compared using a two-tailed t-test. Standard 1% lidocaine was used if additional anesthetic was required.

Measurements and main results: Thirty-one patients were enrolled. Buffered lidocaine was significantly less painful to administer than plain lidocaine (P < .001; t = 4.21). Supplemental anesthesia was required less often for buffered lidocaine (two times) compared with plain lidocaine (six times), although this difference was not statistically significant.

Conclusion: Because it causes less pain and is equally efficacious, buffered lidocaine is preferable to plain lidocaine for digital nerve blocks in adults.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Adult
  • Bicarbonates
  • Buffers
  • Double-Blind Method
  • Female
  • Fingers
  • Humans
  • Injections / adverse effects
  • Lidocaine / administration & dosage*
  • Male
  • Middle Aged
  • Nerve Block*
  • Pain / etiology
  • Pain / prevention & control*
  • Prospective Studies
  • Sodium
  • Sodium Bicarbonate


  • Bicarbonates
  • Buffers
  • Sodium Bicarbonate
  • Lidocaine
  • Sodium