A Comparative Study of Preemptive External Oblique Plane Block and Subcostal TAP Block for Postoperative Analgesia in Radical Cholecystectomy: A Randomised Single-Blinded Prospective Study

Radical cholecystectomy is the standard surgical treatment for gallbladder carcinoma, involving extensive dissection, subcostal incisions, and lymphadenectomy. This results in significant somatic and visceral pain, posing challenges for optimal postoperative analgesia.”

In oncoanesthesia, effective pain control is vital not only for comfort but also to reduce complications, facilitate early recovery, and support immune function.

Systemic opioids have traditionally been the mainstay for analgesia but are associated with several drawbacks: respiratory depression, ileus, sedation, delayed mobilization, opioid tolerance, and immunosuppression—all particularly concerning in cancer patients. Hence, modern cancer care emphasizes opioid-sparing

Ultrasound-guided regional blocks have emerged as safer and more targeted alternatives.

The subcostal TAP block, targeting T6–T9 nerves, provides anterior abdominal wall analgesia but lacks visceral coverage and has limited lateral spread. In contrast, the External Oblique Plane (EOP) block—a newer technique—targets T6–T12 lateral cutaneous branches, potentially offering broader dermatomal coverage. Its superficial location aids visualization and makes it safer in coagulopathic or anatomically altered patients—common scenarios in oncoanesthesia.

Importantly, preemptive administration of these blocks can reduce central sensitization, lower opioid needs, and enhance recovery—core principles of Enhanced Recovery After Surgery (ERAS) in oncology. However, comparative data on EOP versus subcostal TAP blocks in radical cholecystectomy are scarce.

This randomized, single-blinded prospective study aims to compare the analgesic efficacy, opioid-sparing effect, safety, and patient satisfaction of preemptive EOP and subcostal TAP blocks with 0.2% ropivacaine in radical cholecystectomy