Local Anesthetic Response in Ehlers-Danlos Syndrome (EDS) and Healthy Volunteers

Local anesthetic resistance is commonly reported by patients with EDS. However, there are no objective data on the occurrence of local anesthetic resistance in EDS patients and in healthy volunteers. The investigators propose to collect such objective data on the frequency of drug resistance and whether any problems with local anesthesia are due to initial ineffectiveness or due to its effects dissipating too soon.

There was a prior large online questionnaire to better understand the issues around local anesthetic resistance. By November 2018, 933 EDS patients (total 1059 respondents) completed the survey, 99.2% of which had previously received local anesthetics. Among these patients, 88% reported that they have "had a problem with local anesthetic injection not working adequately or properly," while only 54% of respondents without EDS reported a similar problem. These data suggests that local anesthetic resistance might be more prevalent in patients with EDS than in the general population. If these findings are true, then this might have significant implications for the appropriate management of these patients during minor surgery and dental procedures. This study aims to assess the frequency and related issues around local anesthetic resistance in EDS patients, including whether the problem is a lack of analgesia or a timing effect (short duration of action or delayed onset of action), and whether the problem relates only to some local anesthetics or whether there is a problem with the whole class of local anesthetics. This study is completing data originally collected during a 2019 EDS conference.

Patients meeting the diagnostic criteria (2017) for Ehlers-Danlos Syndrome Healthy control volunteers who do not meet the criteria for Ehlers-Danlos Syndrome

Difference between the pain score at the Lidocaine injection locations (compared to a control location) and the saline injection location (compared to a control location). The pain scale is .a 4 level scale from 0 ("absent sensation"), to 1 ("dull pressure"), to 2 ("sharp but less than a control [non-injected] region) to 3 (same or worse than the control region).

Difference between the pain score at the Lidocaine injection locations (compared to a control location) and the saline injection location (compared to a control location). The pain scale is .a 4 level scale from 0 ("absent sensation"), to 1 ("dull pressure"), to 2 ("sharp but less than a control [non-injected] region) to 3 (same or worse than the control region).

Inclusion Criteria: EDS patients, clinically diagnosed hypermobile EDS based on 2017 criteria EDS patients with genetically proven non-hypermobile EDS Healthy participants, no EDS Able and willing to provide informed consent Exclusion Criteria: Known allergy to Lidocaine Unable to provide informed consent