Phrenic Nerve Blockade to Diagnose and Treat Diaphragmatic Pain After Surgical Repair of Congenital Diaphragmatic Eventration

A 46-year-old woman presented with pain in the lateral side of the left chest wall and a sensation of fullness and pulling in the epigastric region, which started 4 weeks following diaphragmatic plication for left diaphragmatic eventration. The patient was diagnosed as suffering from post-thoracotomy pain syndrome (PTPS). A diagnostic intercostal nerve block relieved the chest wall pain, but not the epigastric pain. After a detailed evaluation, the epigastric pain was postulated to be of diaphragmatic origin and hence a diagnostic phrenic nerve block was performed which relieved the epigastric pain. Combined intercostal nerve neurolysis and phrenic nerve block relieved her pain completely. The phrenic nerve may play a role in pain transmission and the genesis of chronic pain following diaphragmatic surgery. Diaphragmatic pain following surgery may contribute to the development of chronic pain. Phrenic nerve blockade provides diagnostic information regarding the etiology of pain as well as being effective in providing analgesia. The technique of phrenic nerve block is presented and its role in the diagnosis and treatment of pain following thoracic surgery is reviewed.