Long-term outcomes of splanchnic radiofrequency ablation for control of chronic abdominal visceral, non-malignant pain

Background and objectives Splanchnic radiofrequency ablation (RFA) is an effective therapy for the treatment of severe abdominal pain. Although it was first described almost 25 years ago, long-term data on longevity and effectiveness are still lacking. Here, we describe the long-term outcomes of a larger retrospective cohort of patients with chronic non-malignant abdominal pain. Methods Following Institutional Review Board IRB approval, patient data were collected from our electronic medical records of 52 patients who underwent splanchnic RFA. Data collected included patients' VAS scores, opioid use, and frequency of nausea at baseline and at 1, 6, and 12 months. We summarized data using descriptive statistics for continuous variables. Student's t-tests and Mann-Whitney U tests were used. Results The mean age of the study participants was 54.3 ± 16.3 years (range, 19–87; median, 57.5), and the mean BMI was 29 kg/m 2 (range, 16–50; median, 27). Forty-one of 52 patients were taking opioids, with a mean opioid dose of 44.5 ± 50.1 mg morphine sulfate equivalents at baseline. The mean baseline VAS pain score was 8.44 ± 1.3 cm, decreasing to 2.73 ± 2.26 cm after the block and to 3.73 ± 2.8, 3.9 ± 2.6, and 4.4 ± 3.8 cm at 1, 6, and 12 months after RFA, respectively. 44/52 patients (85%) had a decrease of 2 or more VAS points at 6 months, and 40/52 patients (77%) at 12 months after RFA. Four patients reported complete pain relief after RFA. At 1 month, 38/52 patients (73%) reported >50% pain relief, 38/52 patients (73%) at 6 months, and 31/52 patients (60%) at 12 months. The mean duration of > 50% of pain relief after RFA was 8.1 months (0-18 months; median 9 months). There was a significant decrease in opioid use at 12 months after RFA (p < 0.001). Patients who underwent a repeat procedure (n = 32) achieved a similar degree of pain relief (p = 0.75). Daily nausea was a major problem in this cohort, with 35 patients reporting severe nausea for an average of 23 days per month. After the diagnostic block, the average number of nausea days decreased to 10.5 (median 4) and further decreased to 9.1 days (median 3; p = 0.001) at 6 months after RFA. Conclusions The majority of patients experienced long-term benefit from splanchnic nerve RFA for the treatment of chronic non-malignant abdominal pain and associated nausea. Moreover, given the very low rate of mild adverse events RFA of the splanchnic nerves is a safe technique that should be considered as a treatment option in patients with chronic visceral abdominal pain.