Clinical Outcomes of Buffered vs. Non-Buffered Lidocaine
Condition: Blood Levels of Buffered vs Non-buffered Lidocaine; Anesthetics, Local
Study type: Interventional

Summary: 
      Anecdotal reports suggest buffering lidocaine with epinephrine just before intraoral
      injection reduces time of onset, results in a deeper anesthetic effect, without the "sting"
      with injection from a low pH. Additional data are needed to establish clinical important
      outcomes such as the peak blood level of lidocaine as compared to the non-buffered drug
      combination.

      Clinical pilot studies are proposed as the start of a series of investigations to support or
      modify the use of the buffered anesthetic for intraoral procedures.
    

Detailed description: 
      Specific Aims:

      Compare blood levels at 30min post injection mandibular block with buffered and non- buffered
      2% lidocaine with 1/100k epinephrine. Assess outcomes (pain levels during and post-injection,
      and onset of anesthesia symptoms) after buffered and non-buffered oral administration of 2%
      lidocaine with 1/100k epinephrine. Assess possible topical anesthetic properties of buffered
      and non-buffered oral administration of 2% lidocaine with 1/100k epinephrine

      Hypotheses:

      No difference in peak blood levels exist between buffered and non-buffered intraoral
      injection of 2% lidocaine with 1/100k epinephrine.

      Injection of buffered local anesthetic will produce less discomfort for the subject as
      compared to the drug with a low pH.

      Buffered local anesthetic will not produce a topical anesthetic effect

      Study Time Frame: 6 months Month One IRB approvals. Recruit volunteers as subjects. Prepare
      case-books. Months Two-Three Clinical Study Months Four-Five Analyze Lab, QOL data Month Six
      Prepare Abstracts, Papers

      Methods: Blinded, Randomized Clinical Design Recruit subjects with IRB approved consent at
      UNC Target enrollment 24 subjects Subjects will serve as their own controls in a cross-over
      AB/BA study design which is uniform within sequences, uniform within periods, and balanced
      Sample size justification: Primary interest is estimation of effect size from pilot study. 24
      subjects should be sufficient to provide data to assess whether a larger study is warranted
      and provide estimates for sample size calculation for larger studies. Vital signs recorded:
      10 min before, during at 30min intervals and after post-anesthetic clinical signs disappear:
      targeted lower lip no longer numb. Randomized subjects to be injected alternatively with 4cc
      of buffered and 4cc non-buffered oral administration of 2% lidocaine with 1/100k epinephrine.

      SAS will be used to create randomization schedules:

      The randomization will be performed first to type of drug given with a balanced randomization
      (half subjects buffered; half to non-buffered) An OMS resident, Dr Phero, will administer the
      drugs in the OMS clinic.

      In week One each subject would receive anesthetic to block the inferior alveolar and lingual
      N; Halstead or Gow-Gates techniques. No Buccal N. block. At least a week later injections
      would involve the alternate local anesthetic combination.

      Venous blood samples would be drawn from the antecubital fossa 30min post oral injection and
      assayed for blood lidocaine levels Timed Assessment: pre, during injection, and
      post-anesthetic for Clinical Onset of Anesthesia Signs: subject reported molar area numbness
      and numb lower lip on ipsilateral injected side. Assessment for pain level on injection;
      modified Likert-type scale

      In addition at each clinic session an assessment of a topical anesthetic effect on
      contralateral lower lip with 5 drops of the injected drug placed on the clinically dry lower
      lip mucosa, Outcome yes/no.

      Data Collection: UNC OMS clinic Venous blood samples (10cc) will be drawn from the
      antecubital fossa 30min post oral injection. Timed assessment pre, during injection, and
      post-anesthetic clinical Signs: molar area anesthesia, incisor area anesthesia, and numb
      lower lip for topical

      Data Collection/Analysis:

      Data will be managed by study staff. Data collection forms and questionnaires for clinical
      data will be developed to use Teleform for direct scanning input into an ACCESS database.
      Similar forms have been used in previous studies. All databases are stored on a password
      protected School of Dentistry server with specific group assignment. SAS will be used for
      database management and statistical analysis. Descriptive statistics are used to verify
      correct entry through range and logical checks.
    

Intervention name(s): Lidocaine
Intervention type(s): Drug
Intervention description(s): See above
Other intervention name(s): Xylocaine
Intervention MeSH terms: Lidocaine
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Care Provider)
Primary purpose: Treatment
Keywords: lidocaine, jaw