Split Face Study of the Duration of Local Anesthetics

Characterizing and Comparing the Duration of Local Anesthetic in Dermatologic Surgery

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.

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.

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