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.

Automated summary

This study aimed to investigate the incidence of and risk factors for opioid withdrawal (OW) among cancer patients who underwent neurolytic splanchnic nerve block (NSNB) and had reduced opioid doses. The study found that OW occurred in 20.8% of the patients within 14 days after NSNB. Longer pain and opioid use duration, as well as a larger opioid tapering dose, may increase the risk of OW.