Innovations and Challenges in Pediatric Liver Surgery: The Role of the Liver Hanging Maneuver

Abstract

The liver hanging maneuver (LHM) is a key surgical approach that enables significant liver resections by providing better control of hepatic mobilization, enhancing exposure, and less intraoperative blood loss. Though well described in adult hepatobiliary surgery, its use in pediatric liver surgery is less addressed. Pediatric surgeons are confronted with specific challenges in terms of differences in anatomy, smaller operative spaces, and differing liver pathology. This article discusses the application of the LHM to pediatric patients, its benefits and limitations, and technical adjustments to accommodate smaller anatomical structures. We also review recent developments, safety issues, and the potential for LHM to enhance outcomes in pediatric liver surgery.

Introduction

Liver resections are possibly the most challenging surgical procedures executed in pediatric patients, usually prompted by congenital liver disease, hepatoblastoma, and other liver tumors. One of the most significant challenges in liver surgery is ensuring sufficient exposure and hemostasis with minimal tissue trauma. The liver hanging maneuver (LHM), first reported by Belghiti et al. in adult liver resections, has transformed hepatic resections by providing a technique to suspend the liver from its superior attachments. Although it has been widely accepted in adults, pediatric surgeons have been slower to incorporate this technique because of the smaller anatomical structures and unique physiological differences of children. The review is centered on the technical adjustments, feasibility, and advantages of LHM in children's liver resections.

Anatomy and Challenges in Pediatric Liver Surgery

The pediatric liver differs from the adult liver in several aspects that impact surgical technique:

• Proportionally Larger Size: In neonates and infants, the liver occupies a significant portion of the abdominal cavity.

• Smaller Vasculature: The hepatic veins and inferior vena cava (IVC) are smaller and more fragile, necessitating meticulous handling.

• High Regenerative Potential: The pediatric liver has a remarkable capacity for regeneration, which influences post-surgical recovery.

• Limited Working Space: The relatively smaller abdominal cavity requires careful maneuvering of surgical instruments.

Given these differences, pediatric surgeons must modify traditional adult techniques, including LHM, to ensure safe and effective application in children.

The Liver Hanging Maneuver: Principles and Adaptation in Pediatric Surgery

LHM involves passing a tape or a vascular sling behind the liver, along the anterior surface of the IVC, to provide suspension during parenchymal transection. The technique consists of three main steps:

1. Creating the Retrohepatic Tunnel: Careful dissection along the anterior surface of the IVC to develop a passage.

2. Passing a Suspension Tape: Avascular planes are utilized to pass a tape between the liver and IVC.

3. Suspension and Control: The liver is gently lifted using the tape, reducing venous congestion and improving surgical exposure.

Technical Modifications for Pediatric Patients

• Smaller Instruments: Given the delicate nature of pediatric tissues, finer instruments, and atraumatic clamps are necessary.

• Selective Dissection: To prevent vascular injury, precise microdissection techniques should be employed.

• Alternative Suspension Materials: In neonates and infants, softer tapes or silicone loops can be used to minimize compression-related injuries.

• Laparoscopic Adaptation: In selected cases, a minimally invasive approach using endoscopic LHM has shown promise.

Clinical Applications of LHM in Pediatric Surgery

The adoption of LHM in pediatric liver surgery can offer several advantages across different conditions:

• Hepatoblastoma Resection: The most common pediatric liver malignancy, hepatoblastoma often necessitates extensive hepatic resection. LHM provides improved visualization and bleeding control, making it a valuable tool.

• Liver Transplantation: During living donor liver transplantation, LHM facilitates precise graft extraction and reduces parenchymal congestion.

• Biliary Atresia Surgery: In select cases where hepatic mobilization is required, LHM can enhance surgical exposure and decrease iatrogenic liver damage.

• Traumatic Liver Injury: For complex hepatic trauma requiring resection, LHM may assist in stabilizing the liver and minimizing intraoperative bleeding.

Advantages of LHM in Pediatric Surgery

• Improved Exposure: Lifting the liver enhances visualization of vital structures.

• Better Hemostasis: By controlling venous congestion, LHM reduces intraoperative bleeding.

• Reduced Liver Mobilization Trauma: Prevents excessive retraction-related injury to the hepatic tissue.

• Facilitation of Major Hepatectomy: Especially useful in complex tumor resections requiring extended hepatic resection.

Limitations and Risks of LHM in Pediatric Patients

Despite its advantages, LHM in pediatric surgery poses certain challenges:

• Risk of IVC Injury: The smaller caliber of the pediatric IVC increases the risk of inadvertent damage.

• Limited Space for Retrohepatic Dissection: Developing a safe retrohepatic tunnel can be difficult in neonates and infants.

• Potential for Vascular Compression: Excessive traction can lead to hemodynamic instability.

• Lack of Standardized Guidelines: Limited pediatric-specific data make it difficult to establish universally accepted protocols.

Recent Advances and Future Directions

As pediatric liver surgery continues to evolve, several advancements are improving the safety and efficacy of LHM:

• Intraoperative Imaging: Real-time ultrasound guidance has enhanced the precision of LHM by helping identify vascular structures.

• 3D Surgical Planning: Preoperative simulation models allow for better surgical planning and risk assessment.

• Robotic-Assisted Surgery: Emerging robotic techniques may refine the application of LHM in minimally invasive pediatric liver resections.

• Artificial Intelligence in Surgery: AI-driven decision-making tools are being explored to predict optimal liver suspension angles and techniques.

Future research should focus on refining these techniques, developing pediatric-specific training modules, and establishing multicenter studies to validate the effectiveness of LHM in children.

Conclusion

The hanging liver maneuver, despite its extensive use in adult hepatobiliary surgery, has great promise in pediatric liver surgery. Its advantages in enhancing exposure, managing bleeding, and aiding in complex resections make it a useful technique for pediatric surgeons. Nonetheless, anatomical and physiological variations in children require modifications in technique and instrumentation. Further studies, technology developments, and training programs will be most important to maximizing the utilization of LHM in pediatric patients and eventually enhancing surgical outcomes and patient safety.