Split Face Study of the Duration of Local Anesthetics

Study Overview
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Brief Summary
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This is a research study to compare how long injectable pain medications (anesthetics) commonly used in dermatologic surgery are effective for. This study will compare a short-acting anesthetic, lidocaine with epinephrine, to one of two long-acting anesthetics (ropivacaine or bupivacaine). This study will also directly compare the duration of actions of ropivacaine and bupivacaine. The investigators hypothesize that the duration of anesthesia of short-acting anesthetics will not differ significantly from long-acting anesthetics at a single site and there will not be a significant difference between the two long-acting anesthetics at a single site.

Detailed Description
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This study will compare the relative durations of local anesthetics within the same subject at a highly vascularized anatomic region of skin, the nasal ala. This study will test and compare the relative durations and efficacy of commonly used long acting (ropivacaine or bupivacaine) and short acting local anesthetics (lidocaine with epinephrine), delivered via local anesthesia. This study will use a modification of a previously published approach of non-invasive pinprick testing to assess the duration of local anesthetic.

Official Title
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Characterizing and Comparing the Duration of Local Anesthetic in Dermatologic Surgery

Conditions
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Anesthetics, Local

Intervention / Treatment
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* Drug: lidocaine + epinephrine 1:100,000
* Drug: Ropivacaine 0.5% Injectable Solution
* Drug: Bupivacaine 0.5% Injectable Solution


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female ≥ 18 years of age Normal skin sensation at both nasal ala assessed by pinprick Ability to provide informed consent Exclusion Criteria: Previous adverse reaction to local anesthetic or any components of the local anesthetics being evaluated Pregnant or breastfeeding volunteers (assessed by self-report) Patients taking monoamineoxidase inhibitors (MAOI) or antidepressants of the triptyline or imipramine types

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Lidocaine + epinephrine vs Ropivacaine<br>Each site of the nasal ala will be tested for normal sensation using sterile 30-gauge needles. Other eligibility criteria will be confirmed. Participants in this arm will receive an injection of 0.5ml of . Xylocaine + epinephrine 1:100,000 (lidocaine + epinephrine 1:100,000), buffered 1/10 with sodium bicarb into one side of the nose (nasal ala) and 0.5ml of Naropin (ropivacaine) 0.5% into the opposite nasal ala. Laterality of each anesthetic administration will be randomly assigned for each patient. Subjects will be evaluated for duration of effect of anesthesia every 15 minutes on both sides of the face, until the patient reports return of a sharp sensation upon the pinprick test. | Drug: lidocaine + epinephrine 1:100,000<br>* 0.5 ml lidocaine + epinephrine 1:100,000, buffered 1/10 with sodium bicarb.<br>* Other names: Xylocaine + epinephrine 1:100,000;Drug: Ropivacaine 0.5% Injectable Solution<br>* 0.5 ml Ropivacaine 0.5% Injectable Solution<br>* Other names: Naropin;|
| Experimental: Lidocaine + epinephrine vs Bupivacaine<br>Each site of the nasal ala will be tested for normal sensation using sterile 30-gauge needles. Other eligibility criteria will be confirmed. Participants in this arm will receive an injection of 0.5ml of lidocaine + epinephrine into one side of the nose (nasal ala) and 0.5ml of Marcaine (bupivacaine) 0.5% into the opposite nasal ala. Laterality of each anesthetic administration will be randomly assigned for each patient. Subjects will be evaluated for duration of effect of anesthesia every 15 minutes on both sides of the face, until the patient reports return of a sharp sensation upon the pinprick test. | Drug: lidocaine + epinephrine 1:100,000<br>* 0.5 ml lidocaine + epinephrine 1:100,000, buffered 1/10 with sodium bicarb.<br>* Other names: Xylocaine + epinephrine 1:100,000;Drug: Bupivacaine 0.5% Injectable Solution<br>* 0.5ml bupivacaine 0.5%<br>* Other names: Marcaine;|
| Experimental: Ropivacaine vs Bupivacaine<br>Each site of the nasal ala will be tested for normal sensation using sterile 30-gauge needles. Other eligibility criteria will be confirmed. Participants in this arm will receive an injection of 0.5ml of Naropin (ropivacaine) 0.5% into one side of the nose (nasal ala) and 0.5ml of Marcaine (bupivacaine) 0.5% into the opposite nasal ala. Laterality of each anesthetic administration will be randomly assigned for each patient. Subjects will be evaluated for duration of effect of anesthesia every 15 minutes on both sides of the face, until the patient reports return of a sharp sensation upon the pinprick test. | Drug: Ropivacaine 0.5% Injectable Solution<br>* 0.5 ml Ropivacaine 0.5% Injectable Solution<br>* Other names: Naropin;Drug: Bupivacaine 0.5% Injectable Solution<br>* 0.5ml bupivacaine 0.5%<br>* Other names: Marcaine;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to Return to Baseline Sensation, as determined by binary outcomes (yes/no) in 15 minute increments | To determine whether the time to return to baseline sensation differs significantly between each pair of anesthetics, the investigators will measure the time to return to baseline sensation at each anesthetized site by asking participants at 15 minute intervals if they can feel a sharp sensation at the site. Sterile needles will be used. The return of the sensitivity will be determined using binary outcomes (yes/no) and recorded on a standardized template. The maximum difference in anesthetic duration that the investigators consider not different from a clinical standpoint is 15 minutes. | Up to 4 hours. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Anesthesia, Mohs, lidocaine, ropivacaine, bupivacaine