Combined Hepatic Hilar and TAP Blocks: An Interventional Radiology Guided Approach to Comprehensive Pain Control

Learning Objectives: 1. Describe the anatomic and physiologic basis of hepatic hilar and transversus abdominis plane (TAP) nerve blocks.


2. Identify clinical scenarios in which combining these two techniques enhances patient outcomes.


3. Review practical, image-guided procedural approaches for performing each block and integrating them into multimodal pain management.

Background: Hepatic hilar nerve blocks (HHNB) target the hepatic plexus at the porta hepatis to reduce visceral pain from hepatobiliary malignancies or liver interventions. Transversus abdominis plane (TAP) blocks anesthetize abdominal wall nerves to relieve somatic pain after abdominal procedures. Each block addresses only part of the pain spectrum. Patients with hepatobiliary cancer or those undergoing interventional procedures often experience mixed visceral and somatic pain, limiting the effectiveness of either technique alone. Recent evidence supports combining HHNB with TAP blocks to achieve broader analgesia and reduced opioid use, with one trial showing lower pain scores and rescue medication needs when both were performed together compared to either block alone {1}.

Clinical Findings/Procedure Details: When used together, the hepatic hilar nerve block (HHNB) is performed first. With the patient supine, ultrasound, CT, or fluoroscopy guides needle placement at the hepatoduodenal ligament, where local anesthetic ± neurolytic agent is injected to block the hepatic plexus and visceral pain. Next, the transversus abdominis plane (TAP) block is performed under ultrasound by injecting local anesthetic between the internal oblique and transversus abdominis muscles to cover somatic pain. Sequencing in one session provides complementary relief, visceral and somatic, especially for patients with hepatobiliary malignancies undergoing abdominal procedures or with tumor invasion of the abdominal wall.

Conclusion and/or Teaching Points: Combined hepatic hilar and TAP blocks provide complementary visceral and somatic pain relief, reduce opioid use, and improve patient comfort. Image guidance makes both techniques feasible and expands radiology's role in multimodal pain management.