Superior hypogastric plexus combined with ganglion impar neurolytic blocks for pelvic and/or perineal cancer pain relief.

BACKGROUND: The superior hypogastric plexus (SHGP) carries afferents from the viscera of the lower abdomen and pelvis. Neurolytic block of this plexus is used for reducing pain resulting from malignancy in these organs. The ganglion impar (GI) innervats the perineum, distal rectum, anus, distal urethra, vulva, and distal third of the vagina. Different approaches to the ganglion impar neurolysis have been described in the literature.

OBJECTIVES: To assess the feasibility, safety, and efficacy of combining the block of the SHGP through the postero-median transdiscal approach with the GI block by the trans-sacro-coccygeal approach for relief of pelvic and/or perineal pain caused by pelvic and/or perineal malignancies or any cancer related causes.

METHODS: Fifteen patients who had cancer-related pelvic pain, perineal pain, or both received a combined SHGP neurolytic block through the postero-median transdiscal approach using a 20-gauge Chiba needle and injection of 10 mL of 10% phenol in saline plus a GI neurolytic block by the trans-sacro-coccygeal approach using a 22-gauge 5 cm needle and injection of 4 - 6 mL of 8% phenol in saline. Pain intensity (measured using a visual analogue scale) and oral morphine consumption pre- and post-procedure were measured.

RESULTS: All patients presented with cancer-related pelvic, perineal, or pelviperineal pain. Pain scores were reduced from a mean (± SD) of 7.87 ± 1.19 pre-procedurally to 2.40 ± 2.10 one week post-procedurally (P < 0.05). In addition, the mean consumption of morphine (delivered via 30 mg sustained-release morphine tablets) was reduced from 98.00 ± 34.89 mg to 32.00 ± 28.48 mg after one week (P < 0.05). No complications or serious side effects were encountered during or after the block.

LIMITATIONS: This study is limited by its small sample size and non-randomized study.

CONCLUSION: A combined neurolytic SHGP block with GI block is an effective and safe technique for reducing pain in cancer patients presented with pelvic and/or perineal pain. Also, a combined SHGP block through a posteromedian transdiscal approach with a GI block through a trans-sacrococcygeal approach may be considered more effective and easier to perform than the recently invented bilateral inferior hypogastric plexus neurolysis through a transsacral approach.