Reducing opioid consumption in postoperative renal transplant patients: A retrospective analysis

Background: Opioid use is high in renal transplant patients, both before and after surgery, in part due to the chronic pain associated with end-stage renal disease. Recent studies have shown patients with high opioid consumption post-transplant have higher incidences of graft loss and mortality. Despite this, opioids remain the mainstay of postoperative analgesia. Aims and Objectives: We wanted to see if known analgesic adjuncts, namely regional anesthesia via a continuous transversus abdominis plane (TAP) catheter block or systemic intravenous lidocaine, could reduce the postoperative opioid requirement in this patient group. Materials and Methods: We conducted a retrospective analysis of renal transplant patients over a 2-year period, comparing patients who had an opioid patient-controlled analgesia pump as their main treatment modality, against patients who had either a TAP block or systemic lidocaine as an adjunct. As a primary outcome measure, we calculated their oral morphine equivalents for the 72 hours post-transplant. We excluded patients who had surgical complications, or were on chronic opioid therapy for other conditions. Results: We identified 86 patients over this study period. We found that regional anesthesia was associated with a 34.4% reduction (P < 0.01) and systemic lidocaine with a 36.5% reduction (P = 0.134) in cumulative opioid consumption without adversely affecting the quality of pain control. No significant complications were noted. Conclusion: Both regional anesthesia and systemic lidocaine are viable opioid sparing adjuncts for postoperative acute pain in this patient population.