Perioperative pain management with regional analgesia techniques for visceral cancer surgery: A systematic review and meta-analysis

Study objective: Regional analgesia following visceral cancer surgery might provide an advantage but evidence for best treatment options related to risk-benefit is unclear. Design: Systematic review of randomized controlled trials (RCT) with meta-analysis and GRADE assessment. Setting: Postoperative pain treatment. Patients: Adult patients undergoing visceral cancer surgery. Interventions: Any kind of peripheral (PRA) or epidural analgesia (EA) with/without systemic analgesia (SA) was compared to SA with or without placebo treatment or any other regional anaesthetic techniques. Measurements: Primary outcome measures were postoperative acute pain intensity at rest and during activity 24 h after surgery, the number of patients with block-related adverse events and postoperative paralytic ileus. Main results: 59 RCTs (4345 participants) were included. EA may reduce pain intensity at rest (mean difference (MD) -1.05; 95% confidence interval (CI): -1.35 to -0.75, low certainty evidence) and during activity 24 h after surgery (MD -1.83; 95% CI: -2.34 to -1.33, very low certainty evidence). PRA likely results in little difference in pain intensity at rest (MD -0.75; 95% CI: -1.20 to -0.31, moderate certainty evidence) and pain during activity (MD -0.93; 95% CI: -1.34 to -0.53, moderate certainty evidence) 24 h after surgery compared to SA. There may be no difference in block-related adverse events (very low certainty evidence) and development of paralytic ileus (very low certainty of evidence) between EA, respectively PRA and SA. Conclusions: Following visceral cancer surgery EA may reduce pain intensity. In contrast, PRA had only limited effects on pain intensity at rest and during activity. However, we are uncertain regarding the effect of both techniques on block-related adverse events and paralytic ileus. Further research is required focusing on regional analgesia techniques especially following laparoscopic visceral cancer surgery.