Evidence Hub

Patients with Ehlers-Danlos Syndrome Experience Reduced Effectiveness of Lidocaine Local Anesthetic: A Randomized Cross-Over Clinical Trial

K. Bourne, Serra Thai, L. Lei, T. Siddiqui, Bonnie Black, Amanda C. Peltier, S. Paranjape, C. Shibao et al.

Regional anesthesia and pain medicine, 2026

135 participants · 1 citation

Abstract

Background The Ehlers-Danlos syndromes (EDS) are a collection of heritable connective tissue disorders. Local anesthetic resistance is commonly reported by patients with EDS, but there is little clinical evidence to support this finding. We hypothesized that patients with EDS would have increased anesthetic resistance using lidocaine compared with healthy controls. Methods An interventional study design was used. Participants (total N=135: EDS n=91, healthy n=44) completed a series of sensation tests using a standardized 10 g monofilament following subcutaneous injection with saline or lidocaine at two separate sites on the right forearm in a randomized order. Participants rated their sensation at each site relative to non-anesthetized skin. Sensation was used as a surrogate measure of anesthetic effect. Participant ratings were converted into two measures: (1) a dichotomous variable to represent adequate anesthesia and (2) a delta sensation score. This study was registered on ClinicalTrials.gov (NCT05603741). Results Delta sensation scores were not different at 5 min post-injection between EDS and healthy participants (p=0.2), but were significantly different at 15 min (1 (0–2) arbitrary units (a.u.) vs 2 (1–2) a.u; p=0.002) and 30 min (1 (0–2) a.u. vs 2 (1–2) a.u.; p=0.003) post-injection. There was no difference in categorical “anesthesia” at 5 min between EDS and controls (p=0.2). A smaller proportion of EDS experienced “anesthesia” at 15 min (60% vs 84%, p=0.006) and 30…

How strong is the evidence?

Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design. Reported size: 135 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free