Erector Spinae Plane (ESP) Block Volunteer Study

Although erector spinae plane (ESP) block reportedly provides postoperative pain relieve, controversy remains regarding the accuracy and consistency of analgesic success following ESP block. The goal of this study is to determine the extent and duration of clinical neural blockade following an ESP injection with different local anesthetic doses. Methods Twenty four healthy volunteers will be recruited, and each subject will make 2 separate visits to the study centre to undergo intervention and assessment. The 2 study visits will be separated by an interval of at least 2 weeks to ensure complete washout of any residual effects and a return to baseline status. At each study visit, the subject will receive a unilateral ESP block with 1.5% lidocaine and 5 mcg/mL epinephrine. Two different local anesthetic volumes will be investigated: 20 mL (300 mg lidocaine) at one study visit and 30 mL (450 mg lidocaine) at the other study visit. Volunteers will be randomized to one of two intervention groups: (1) Group 20/30: A unilateral ESP block with 20 mL of local anesthetic at the first visit, and 30 mL of local anesthetic at the second visit; or (2) Group 30/20: a unilateral ESP block with 30 mL of 1.5% lidocaine with 1/200,000 epinephrine at the first visit, and 20 mL of the same local anesthetic solution at the second visit. There will be 2 study subgroups based on the vertebral level at which the ESP block is administered: (1) Volunteer subjects in subgroup TP4 will receive the ESP block injection at the T4 transverse process (TP4) level in order to evaluate the anesthetic effect on the chest wall. (2) Volunteers in subgroup TP8 will receive the ESP block injection at the T8 transverse process (TP8) level in order to evaluate the anesthetic effect on the abdominal wall. The first 10 volunteer subjects recruited will receive ESP blocks at the TP4 level and the subsequent 10 subjects will receive ESP blocks at the TP8 level.

NCT Number	NCT04401007
Lead Sponsor	University Health Network, Toronto
Conditions	Pain Management
Enrollment	12 participants
Start Date	2021-07-28
Primary Completion	2023-11-20 (estimated)
Study Completion	2023-11-20 (estimated)
Updated on ClinicalTrials.gov	2026-07-31