Dispersion Following ESP Versus ITP Blocks Using Lidocaine Study

Summary

Regional anesthesia techniques (or nerve blocks) are used to provide sensory blockade over the chest wall. The most established technique is thoracic epidural. This provides bilateral spread but is also associated with neuraxial complications, which has led to a decrease in clinical usage. Alternative peripheral nerve block techniques, such as intercostal nerve blocks, eliminate the neuraxial complications but, in turn, require numerous injections to provide unilateral coverage. The introduction of ultrasound-guided (USG) nerve blocks has generated clinical interest in the development of novel paraspinal (non-epidural) nerve block techniques, which will provide multiple dermatomal coverage with a single injection. Two such techniques are the Erector Spinae Plane (ESP) block and the Intertransverse Process (ITP) block. The Intertransverse Process (ITP) block targets a slightly deeper plane than the Erector Spinae Plane (ESP) block and was specifically designed to address the ESP block's variable anesthetic spread. Despite its potential for more localized and precise dermatomal coverage, no prior studies have directly compared the two techniques in terms of their cutaneous distribution.

Thus, this randomized, double-blinded trial aims to compare the cutaneous distribution of both these blocks in healthy adult volunteers. To compare the dermatomal sensory block distribution, the investigators will use detailed mapping with pinprick, cold, and heat stimuli.

In addition to assessing the distribution and coverage of the ESP and ITP blocks, this study also seeks to investigate the pharmacokinetics (PK) of lidocaine in each technique. The rationale for this lies in the anatomical differences between the two blocks. Theoretically, there may be a difference in the anatomical target for both blocks, but the investigators hypothesize that there is no difference in the local anesthetic absorption. Therefore, the investigators expect similar systemic absorption, the chances of local anesthetic systemic toxicity (LAST) should be equally low, and both blocks should be similarly safe.

A total of 14-18 healthy adult volunteers will be included. There will be two different procedure days, separated by at least one week. On each day, the subjects will receive a paraspinal block, according to the randomization process. Each volunteer will undergo pre-procedure screening on the first visit. The blocks will be performed on the same side, at the same level, by the same anesthesiologist, at least one week apart. An ultrasound-guided ESP block will be administered in one day, and an ITP block on the other. The order will be randomized, and both the subject and the research team member assessing the block will be blinded. Sensory testing will be performed at baseline and 60-90 minutes after the block injections. Serial samples of blood will be drawn to analyze lidocaine PK (between 0 and 240 minutes post-block).

Conditions

• Acute Pain, Postoperative
• Regional Anesthesia Block

Interventions

PROCEDURE

Intertransverse Process Block with 1.5% Lidocaine

For the ITP block, the needle will be advanced further into the intertransverse tissue complex between the T4 and T5 transverse processes, and local anesthetic will be injected just above the superior costotransverse ligament, under ultrasound guidance.

PROCEDURE

Erector Spinae Plane Block with 1.5% Lidocaine

The ESP block will be performed by advancing the needle to the transverse process, under ultrasound guidance, with local anesthetic injected between the erector spinae muscle and the transverse process, targeting a caudad-cephalad spread.

DRUG

1.5% Lidocaine

local anesthetic to be used in either the ITP and ESP block

Sponsors & Collaborators

• Duke University

  lead OTHER

Principal Investigators

• Brian Mendelson, MD · Duke University

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-06-10

Primary Completion

2025-07-26

Completion

2025-08-01

FDA Drug

Yes

Countries

• United States

Study Locations