A Literature Review of Intrathecal Morphine Analgesia in Patients Undergoing Major Open Hepato-Pancreatic-Biliary (HPB) Surgery

CONTEXT: The optimal analgesic method for patients undergoing major open hepato-pancreatic-biliary surgery remains controversial. Continuous epidural infusion at the thoracic level remains the standard choice, however concerns have been raised due to associated complications. Single shot intrathecal morphine has emerged as a promising alternative offering similar analgesia with an enhanced safety profile. EVIDENCE ACQUISITION: This review aimed to evaluate the literature comparing intrathecal morphine analgesia to other analgesic modalities following major open hepato-pancreatic-biliary surgery. The primary outcome was pain scores at rest and on movement 24 h after surgery. Secondary outcomes were postoperative opioid consumption within 72 postoperative hours, length of stay (LOS), intra-operative fluid administration and post-operative fluid administration within 72 postoperative hours, and overall systemic complication rate within 30 postoperative days. RESULTS: Eleven trials matching the inclusion criteria were analysed. Intrathecal morphine resulted in equivalent or lower pain scores when contrasted to alternative techniques, but required higher amounts of postoperative opioid. Intrathecal morphine also offered reduced LOS and reduced fluid administration requirements to epidural analgesia, and there was no difference observed in major complication rate between analgesic modalities. CONCLUSIONS: In summary the evidence suggests that intrathecal morphine may be a better first-line analgesic modality than epidural analgesia in the context of major open hepato-pancreatic-biliary surgery, but high-quality evidence supporting this is limited.