Transversus abdominis plane block: a cadaveric and radiological evaluation

Area of Science:

• Anesthesiology
• Surgical Pain Management
• Regional Anesthesia

Background:

• Abdominal surgery frequently causes significant postoperative pain originating from the anterior abdominal wall.
• Effective anterior abdominal wall analgesia is crucial for improving patient recovery and managing postoperative pain.
• The transversus abdominis plane block is a novel technique targeting abdominal wall neural afferents.

Purpose of the Study:

• To define the anatomic characteristics and spread of the transversus abdominis plane block.
• To evaluate the in vivo deposition and time course of solution spread within the transversus abdominis fascial plane.
• To establish the clinical potential of this novel regional anesthesia technique.

Main Methods:

• Anatomic studies using methylene blue injection via the triangles of Petit in cadavers.
• In vivo imaging studies (CT and MRI) in volunteers to assess solution spread and deposition.
• Evaluation of sensory block extent and duration following local anesthetic injection.

Main Results:

• Cadaveric studies confirmed reliable deposition into the transversus abdominis plane using the "double pop" technique via the triangle of Petit.
• Volunteer studies demonstrated reliable sensory block and consistent spread of injected solution within the transversus abdominis plane.
• Lidocaine 0.5% produced a sensory block from T7 to L1, lasting 4-6 hours, with MRI confirming gradual contrast reduction over time.

Conclusions:

• The transversus abdominis plane block is anatomically defined and reliably targets the transversus abdominis plane.
• The technique demonstrates significant clinical potential for managing anterior abdominal wall pain post-surgery.
• This novel block offers a promising approach to improving postoperative analgesia in abdominal surgery patients.