Intrathecal Morphine Versus Nerve Blocks in an Enhanced Recovery Pathway for Pancreatic Surgery

Intrathecal morphine (ITM) and peripheral nerve blocks are accepted techniques for analgesia after abdominal surgery, but their efficacy has not been evaluated in the context of an enhanced recovery pathway (ERP) in pancreatic surgery.

We retrospectively compared postoperative analgesia (pain scores and opioid requirements) after open or robotic pancreatoduodenectomy or distal pancreatectomy among ERP patients receiving either ITM or transversus abdominis plane/quadratus lumborum (TAP/QL) nerve blocks.

We identified 303 ERP patients who underwent pancreatectomy with either ITM (n = 251) or TAP/QL blocks (n = 52). Patient demographics and procedural variables were similar between groups. Few preoperative patient characteristics (preoperative stroke and pain medication intake) differed between the two groups. In an unmatched patient cohort, the median pain score on postoperative day (POD 0) zero was 4.5 (interquartile range [IQR] 2.3-5.8) in ITM patients compared with 5.7 (IQR, 3.4-6.9) in patients who received TAP/QL (P < 0.05). Median opioid consumption in intravenous morphine equivalents on POD 0 was 2.7 mg (IQR, 0-11.7) in ITM patients compared with 8.4 mg (IQR, 2.5-20.8) in TAP/QL patients (P < 0.001). After propensity matching for patient characteristics, pain scores and opioid consumption were significantly (P < 0.05) lower on POD 0 and POD 5 in patients who received ITM. The difference in quality of analgesia between ITM and TAP/QL was also maintained in the pancreaticoduodenectomy and distal pancreatectomy subgroups. Extubation in the operating room was achieved in a higher percentage of patients receiving ITM (92%) compared with those receiving TAP/QL (63%). The incidence of postoperative nausea and vomiting was similar in both groups.

ITM was associated with reduced pain scores and opioid requirements compared with peripheral nerve blocks in an ERP for pancreatic surgery.