EOI Didn’t See That Coming: External Oblique Intercostal Plane Block for an Unexpected Open Cholecystectomy Alexander Linse MD, Aidan Hoie MD University of Colorado • 64 male presenting for robotic cholecystectomy. • Unexpectedly converted to open. • Acute Pain Service consulted for epidural: o Received heparin for DVT prophylaxis o Not consented for this pre-operatively o Deferred until the patient was able to participate in shared decision making. o Truncal nerve block was pursued, consent from MDPOA • Ultrasound guided EOI block was performed • Postoperatively, reported excellent pain control, required only scheduled acetaminophen • Did not require epidural or opioids during his recovery and was discharged on POD 2 without additional analgesics. • External oblique intercostal (EOI) nerve blocks provide upper abdominal wall analgesia • Target the lateral and anterior cutaneous branches of the T6–T10 intercostal nerves superficial to the external oblique muscle. • This dermatomal coverage offers effective analgesia from the anterior axillary line to midline [1] • Patient consent obtained for case reporting. • Literature review exploring the safety and efficacy of EOI blocks • IRB review not required per Colorado Multiple Institutional Review Board guidelines and no identifiable patient data is presented. • Superficial, easily identifiable fascial plane block: o Less invasive than neuraxial o Anticoagulation not a contraindication o Both laparoscopic and open surgeries.[2] • Helped preserve patient-centered care while providing effective analgesia. • Prior studies have demonstrated EOI efficacy in o Open hepatectomy o Liver transplantation o Thoracotomy • Direct comparisons with epidural analgesia are lacking and remain an area of future study. [3,4] 1 2 3 4