38 Transversus Abdominis Plane Block
Perspective
The transversus abdominis plane (TAP) block is used for patients undergoing surgeries involving anterior abdominal wall incisions. The TAP block provides analgesia to the anterior abdominal wall. The lateral abdominal wall comprises three layers of muscle and their associated fascia: the most superficial muscle is the external oblique; deep to this is the internal oblique; and still deeper is the transversus abdominis. The anterior rami of the lower six thoracic and first lumbar nerves provide sensation to the skin, muscles, and parietal peritoneum of the anterior abdominal wall. After exiting the vertebral column’s foramina, these nerves pass through the lateral abdominal wall within the fascial plane between the internal oblique and transversus abdominis muscles (the transversus abdominis neurofascial plane; Fig. 38-1). Injecting local anesthetic into the fascial plane between the internal oblique and transversus abdominis muscles produces the TAP block.
