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Background and Aims Effective postoperative pain management is challenging after open hepatobiliary surgery. Our trust increasingly uses spinal anaesthesia with regional techniques such as preperitoneal wound catheters (inserted by the surgeon prior to wound closure) and external oblique intercostal (EOI) blocks. The EOI is a novel block to deposit local anaesthetic in the fascial plane between the intercostal and external oblique muscles at sixth rib level. Case studies and cadaveric work offer positive evidence basis. We aim to evaluate the efficacy of both techniques.

Methods We collected retrospective data from consecutive HPB surgery patients who received spinal anaesthesia and either EOI block catheters or wound catheters. Data collected included pain scores, PCA requirements, time in HDU, length of stay, and time to bowel function and soft diet initiation.

Results Patients reported mild to moderate postoperative pain suggesting that both techniques, as part of multi-modal analgesia, are effective. EOI blocks may be a superior technique to wound catheters as patients who received EOI blocks had shorter stays in HDU, were discharged earlier, and reported lower pain scores. They also had earlier removal of PCAs, mobilisation, return of bowel function, and initiation of soft diet.

Conclusions Our study highlights the importance of evaluating and optimising postoperative pain management techniques ensuring patients receive the best possible care. The use of both preperitoneal wound catheters and EOI blocks, in combination with spinal anaesthesia, appear to provide effective analgesia these patients. Further work is needed to confirm the superiority of EOI blocks over wound catheters.

Attachment EOIB audit form2 Section 1.doc