Opioid withdrawal symptoms after neurolytic splanchnic nerve block in cancer patients.

PURPOSE: Few reports on opioid withdrawal (OW) due to opioid tapering in cancer patients have been published. The incidence of and risk factors for OW after neurolytic splanchnic nerve block (NSNB) are unknown. This study aimed to elucidate the incidence of and risk factors for OW among cancer patients who could have reduced opioid doses after NSNB. METHODS: This was a multicenter, retrospective, observational study. We reviewed the medical charts of patients who underwent NSNB for intractable cancer pain at four tertiary hospitals in Yokohama City from April 2005 to October 2020. We included patients whose opioid dose was reduced by > 5 mg/day (equivalent oral morphine dose) within 14 days after NSNB. We classified the patients into two groups according to the presence or absence of OW symptoms and compared them. RESULTS: Of the 50 patients who underwent NSNB, 24 were included in the study. OW was observed in five (20.8%) patients. Pain and opioid use duration were significantly longer in OW patients than in non-OW patients (median pain duration 689 vs. 195 days; P < 0.043 and median opioid use duration 486 vs. 136 days; P < 0.030). The opioid tapering dose was significantly larger in patients with OW than in those without OW (median opioid tapering dose 75 vs. 40 mg; P < 0.046). CONCLUSIONS: OW was observed in 20.8% of the patients in the study. A longer pain and opioid use duration and a larger opioid tapering dose may predispose patients to OW.

Long-Term Analgesic Efficacy of Neurolytic Splanchnic Nerve Block via the Transintervertebral Disc Approach to Retrocrural Space: A Multicenter Retrospective Study.

INTRODUCTION: The celiac plexus block is effective for treating intractable cancer pain and has been the focus of many studies. At our affiliated institution, fluoroscopy-guided splanchnic nerve block with a single needle via the transintervertebral disc approach was the first choice of treatment. The short-term efficacy of this technique has been reported, but the long-term efficacy is not clear. In the present study, we investigated the long-term analgesic efficacy of this technique. METHODS: This multicenter, retrospective, observational study reviewed the medical records of patients who underwent neurolytic splanchnic nerve block (NSNB) via the transintervertebral disc approach for intractable cancer pain at five tertiary hospitals in Japan from April 2005 to October 2020. The primary outcome was the long-term analgesic efficacy of a one-time NSNB via the transintervertebral disc approach. RESULTS: In total, 76 patients were included in the analysis. The median lowest numerical rating scale (NRS) score was 1 within 14 days. At 1, 2, 3, and 6 months after the nerve block, the median NRS score was also ≤ 2, while the median equivalent oral morphine dose did not show any clinically noticeable increase at those times. CONCLUSION: The long-term analgesic efficacy of NSNB via the transintervertebral disc approach in patients with intractable cancer pain has been demonstrated.

The celiac plexus block is effective for treating intractable cancer pain and has been the focus of many studies. The celiac plexus nerve block relieves intractable cancer pain arising from the pancreas or other organs in close proximity, and the splanchnic nerve block is considered clinically equivalent to the celiac plexus block for analgesia. At our affiliated institution, fluoroscopy-guided neurolytic splanchnic nerve block with a single needle via the transintervertebral disc approach is the first choice of treatment because it is technically simpler and less invasive than other approaches. While the short-term efficacy of this technique is known, its long-term efficacy remains unclear. Thus, this multicenter, retrospective, observational study aimed to investigate the long-term analgesic efficacy of a neurolytic splanchnic nerve block via the transintervertebral disc approach. The medical records of patients in whom intractable cancer pain was managed using this technique at five tertiary hospitals in Japan were analyzed. The primary outcome was the long-term analgesic efficacy of a one-time neurolytic splanchnic nerve block via the transintervertebral disc approach. The median lowest numerical rating scale score was 1 within 14 days. At 1, 2, 3, and 6 months after the nerve block, the median numerical rating scale score was also ≤ 2, while the median equivalent oral morphine dose did not show any clinically noticeable increase at those times. This technique may reduce opioid dose and associated side effects compared with long-term conventional pharmacotherapy alone.

Efficacy and Safety of Neurolytic Splanchnic Nerve Block via Transintervertebral Disc Approach to Retrocrural Space: A Multicenter Retrospective Study.

INTRODUCTION: Celiac plexus block is effective for treating intractable cancer pain and has been the focus of many studies. Several guiding techniques such as fluoroscopy, computed tomography, and endoscopy have been devised, and the target of the block has varied in previous studies as both the celiac plexus and splanchnic nerve, which is the main origin of the celiac plexus, have been targeted. At our affiliated institution, fluoroscopy-guided splanchnic nerve block with a single needle via transintervertebral disc approach is the first choice. However, there have been few reports on the use of this technique. This study investigated the efficacy and safety of this technique. METHODS: This multicenter retrospective observational study reviewed the medical records of patients who underwent neurolytic splanchnic nerve block (NSNB) via transintervertebral disc approach for intractable cancer pain at five tertiary hospitals in Japan from April 2005 to October 2020. The primary outcome was the clinical success ratio of NSNB, and the secondary outcome was the incidence ratio of NSNB-related adverse events. RESULTS: In total, 103 patients were included in the analysis. Of these, 77 patients met the definition of clinical success, with a ratio of 74.8%. The incidence ratio of NSNB-related adverse events was 40.8% (hypotension, 21.4%; alcohol intoxication, 13.6%; diarrhea, 11.7%; and vascular puncture, 3.9%; duplicates were present). All adverse events improved with observation and symptomatic treatment only. No patient had infection or serious adverse events such as organ or nerve damage. CONCLUSIONS: The clinical success ratio of this technique was 74.8%. Although the incidence of adverse events was 40.8%, all events were mild and no serious adverse events were observed. The findings demonstrate the efficacy and safety of our NSNB in patients with intractable cancer pain.

In patients with intractable pain from abdominal cancer, fluoroscopy-guided neurolytic splanchnic nerve block via transintervertebral disc approach is an effective and safe procedure. It can be completed with a single needle puncture, and is anatomically less likely to cause organ or nerve damage compared with other approaches. The analgesia produced by this technique, along with conventional pharmacotherapy for cancer pain, may reduce opioid dose and its side effects and improve patients' quality of life.

Adhesions in the epidural space caused by frequent epidural blocks.

We report a case of adhesions in the epidural space caused by more than 200 times epidural blocks that were observed with epiduroscopy. A 41-year-old man had repeatedly undergone lumbar epidural blocks to treat pain in his leg, resulting in decreased efficacy of the epidural block. We described endoscopic findings that these adhesions were mostly consisted of adhesions formed from the soft connective tissue.