title: Reducing the discomfort of lidocaine administration through pH buffering.
abstract: OBJECTIVE
  A prospective, double-blind study was undertaken to evaluate the effect of using a buffered lidocaine solution on the perception of pain experienced by a patient during its intradermal injection.
  
  
  METHODS
  One hundred fifty patients undergoing diagnostic angiographic and interventional procedures at the authors' institution were randomly assigned to receive a 1-mL aliquot of one of three lidocaine solutions: plain 1% lidocaine, 1% lidocaine diluted with normal saline in a 10:1 ratio, and 1% lidocaine diluted with 8.4% sodium bicarbonate in a 10:1 ratio. The lidocaine solutions were administered intradermally over 10-15 seconds. A numerical value was placed on the patient's perception of pain, separate from that associated with the 25-gauge needle insertion, with use of a linear visual analog scale.
  
  
  RESULTS
  Mean pain scores were as follows: for the 1% lidocaine solution, 2.83 +/- 2.60; for 1% lidocaine plus normal saline solution, 2.89 +/- 2.34; and for 1% lidocaine plus sodium bicarbonate solution, 1.37 +/- 1.73 (P = .0018).
  
  
  CONCLUSIONS
  Buffering lidocaine significantly decreased the discomfort associated with its administration as a local anesthetic.
authors.affiliation: Department of Radiology, University of Virginia Health Sciences Center, Charlottesville 22908.
authors.forename: A H
authors.initials: AH
authors.lastname: Matsumoto
authors.forename: A C
authors.initials: AC
authors.lastname: Reifsnyder
authors.forename: G D
authors.initials: GD
authors.lastname: Hartwell
authors.forename: J F
authors.initials: JF
authors.lastname: Angle
authors.forename: J B
authors.initials: JB
authors.lastname: Selby
authors.forename: C J
authors.initials: CJ
authors.lastname: Tegtmeyer
mesh_terms: D000293:Adolescent; D002021:Buffers; D004311:Double-Blind Method; D006801:Humans; D007271:Injections, Intradermal / Q000009:adverse effects*; D008012:Lidocaine / Q000008:administration & dosage* / Q000009:adverse effects; D008875:Middle Aged; D010146:Pain / Q000517:prevention & control*; D011446:Prospective Studies; D017693:Sodium Bicarbonate
chemical_list: D002021:Buffers; D017693:Sodium Bicarbonate; D008012:Lidocaine