Ultrasound-guided peripheral nerve blocks for anterior cutaneous nerve entrapment syndrome after robot-assisted gastrectomy: A case report.

Background: Anterior cutaneous nerve entrapment syndrome (ACNES) is a condition manifesting with pain caused by strangulation of the anterior cutaneous branch of the lower intercostal nerves. This case report aims to provide new insight into the selection of peripheral nerve blocks for the ACNES treatment.

Case summary: A 66-year-old woman manifested ACNES after a robot-assisted distal gastrectomy. An ultrasound-guided rectal sheath block was effective for pain triggered by the port scar. However, the sudden severe pain, which radiated laterally from the previous site, remained. A transversus abdominis plane block was performed for the remaining pain and effectively relieved it.

Conclusion: In this case, the trocar port was inserted between the rectus and transverse abdominis muscles. The intercostal nerves might have been entrapped on both sides of the rectus and transversus abdominis muscles. Hence, rectus sheath and transverse abdominis plane blocks were required to achieve complete pain relief. To the best of our knowledge, this is the first report on use of a combination of rectus sheath and transverse abdominis plane blocks for pain relief in ACNES.