Neurolytic Transversus Abdominal Plane Block with Alcohol for Long-Term Malignancy Related Pain Control

Abstract

There have been several case reports in the literature of neurolytic transversus abdominis plane (TAP) blocks being used for malignant abdominal wall pain. However, most used phenol as a neurolytic agent. We found only a single case report by Sakamoto using alcohol for TAP neurolysis. Unfortunately this patient passed away only 5 days after performance of the block. We attempt to extend upon the existing literature by describing neurolytic TAP blockade outcomes using alcohol on 3 cancer patients with metastatic disease to the abdominal wall. Two of our 3 patients had colorectal cancer invading the abdominal musculature. The third patient had a metastatic neuroendocrine nodule in the left rectus muscle. In our case series, all 3 patients had sustained and significant (greater than 50%) relief of abdominal wall pain after performing TAP neurolysis using alcohol. Ultrasound guidance was used for all blocks. The concentration of alcohol used varied from 33% to 77% between patients. Duration of relief lasted between 17 days and 6 months. Opioid use either decreased or remained relatively stable for prolonged periods of time after neurolysis. Other than one patient with transient post-procedure pain related to alcohol injection, there were no significant complications. Addition of a depo steroid for diagnostic TAP blockade prior to neurolysis did not appear to extend or provide additional analgesia. Based on our observations, TAP neurolysis using alcohol also offers a feasible option for longterm control of malignant abdominal wall pain. Further investigation is needed to determine if alcohol offers any significant advantage compared with phenol. Key words: Transversus abdominis plane block, TAP Block, cancer pain, neurolysis, alcohol, ultrasound, abdominal pain, interventional pain management