Comparison Between Two Volumes of 70% Alcohol in Single Injection Ultrasound-Guided Celiac Plexus Neurolysis: A Randomized Controlled Trial

Background: Pain due to inoperable upper abdominal malignancies is a challenging condition that needs a multimodal analgesic regimen to be managed properly. Celiac plexus alcohol neurolysis was proved to be effective in relieving such type of pain; however, there is no consistent data about the optimal volume to be used to maintain the balance between the neurolytic effect and the destructive effect of alcohol. Objectives: We aim to compare the analgesic effect of 2 different volumes of alcohol to improve the outcome of interventional management. Study Design: This was a randomized controlled double-blinded interventional clinical trial. Setting: Single university hospital. Methods: Thirty-two patients who suffered from abdominal pain due to unresectable abdominal malignancies were randomly allocated to receive in a single injection ultrasound-guided celiac plexus neurolysis (CPN) with injection of either 20 mL 70% alcohol (CPN20 group) or 40 mL 70% alcohol (CPN40 group). The primary outcome was the post-procedure pain score, while the secondary outcomes included the post-procedure total daily opioid consumption and quality of life (QOL). Results: There was no statistically significant difference between both groups regarding visual analog scale (VAS) scores at all time points (P-value > 0.05); however, comparisons in each group revealed significantly reduced VAS scores at all time points following the intervention when compared to the baseline. Daily morphine equivalent consumption doses showed statistically significant differences between the baseline and each time point in both groups (P value < 0.05), with no significant difference between both groups at each time point (P value > 0.05). There was no statistically significant difference between the study groups regarding all domains in quality of life assessment at all time points (Pvalue > 0.05). The scores of most time points in all domains were different significantly when compared to the baseline readings in both groups, with a tendency to decline over time in both groups approaching the baseline values. Limitations: This was a single-center study with a relatively small sample size. Further prospective, multicenter, randomized, and controlled studies with a larger sample size are required to confirm the effects in this study. Conclusions: During ultrasound-guided CPN for patients with inoperable upper abdominal cancers who failed medical management, a volume of 20 mL is as effective as 40 mL of 70% alcohol regarding pain control, opioid consumption, quality of life, and procedure-related complications.