Overview
Definition:
Exposure and control of the retrohepatic segment of the Inferior Vena Cava (IVC), the large vein returning deoxygenated blood from the lower and middle body to the heart
this is a technically demanding surgical manoeuvre often required in complex abdominal, hepatic, or trauma surgery.
Epidemiology:
The need for retrohepatic IVC control arises in specific surgical scenarios, including major liver resections, trauma involving hepatic veins or the suprahepatic IVC, and management of IVC tumors or fistulas
Its incidence is tied to the prevalence of these complex conditions.
Clinical Significance:
Accurate and safe exposure and control of the retrohepatic IVC are critical for managing major haemorrhage during liver surgery and trauma
Inadequate control can lead to catastrophic blood loss, while excessive or improper control can cause hepatic congestion and ischaemic injury, impacting patient survival and outcomes.
Indications
Hepatic Resection:
Major hepatic resections involving segments 1, 7, or 8, or extensive trisegmentectomies require isolation of the retrohepatic IVC to manage inflow from hepatic veins.
Trauma:
Penetrating or blunt trauma to the abdomen resulting in direct injury to the retrohepatic IVC or major hepatic veins requires urgent control.
Ivc Pathology:
Resection of IVC tumors (e.g., leiomyosarcoma), management of IVC arteriovenous fistulas, or repair of congenital anomalies of the IVC.
Transplantation:
Orthotopic liver transplantation necessitates meticulous dissection and control of the suprahepatic and retrohepatic IVC segments for anastomoses.
Preoperative Preparation
Imaging:
Preoperative imaging (CT angiography, MRI venography) is essential to delineate the anatomy of the retrohepatic IVC, hepatic veins, and surrounding structures
identify potential anomalies or pathologies like tumors.
Anesthesia And Monitoring:
Close hemodynamic monitoring is paramount
Consider invasive arterial pressure monitoring and central venous pressure monitoring
An anesthesiologist experienced in major abdominal surgery and massive transfusion protocols is crucial.
Blood Products:
Anticipate the need for massive transfusion
Ensure adequate availability of packed red blood cells, fresh frozen plasma, platelets, and cryoprecipitate.
Surgical Team:
Assemble an experienced surgical team, including vascular and hepatic surgeons, and skilled surgical assistants
A comprehensive understanding of anatomical variations is vital.
Exposure And Control Techniques
Approach:
The surgical approach is typically a midline laparotomy or subcostal incision, often extended to a Mercedes-Benz incision for extensive liver exposure
Mobilization of the liver, particularly the right lobe, is key.
Ligation Of Hepatic Veins:
Pre-ligation of smaller hepatic veins can sometimes facilitate IVC mobilization
However, it’s crucial to identify and preserve major hepatic veins if possible, especially in transplantation.
Pringle Manoeuvre:
Portal triad clamping (Pringle manoeuvre) may be performed to reduce hepatic blood flow and congestion, aiding in IVC dissection and control, but should be used judiciously due to potential ischaemic injury.
Parahepatic Dissection:
Dissection is performed meticulously along the anterior surface of the IVC, identifying the origin of the hepatic veins
Careful blunt and sharp dissection, using fine instruments and electrocautery, is necessary to avoid injury.
Ivc Occlusion Devices:
Various occluding devices may be used, including vascular clamps (Satinsky, bulldog clamps), intraluminal shunts, or temporary balloon occlusion catheters placed under direct vision.
Complete Mobilization:
Achieving complete mobilization requires careful dissection from the diaphragm superiorly and Gerota's fascia inferiorly, often involving division of the muscles of the diaphragm adjacent to the IVC
The suprahepatic IVC is controlled after the retrohepatic segment.
Management Of Bleeding
Initial Response:
Immediate direct pressure with sponges and meticulous haemostasis are the first steps
Suction should be readily available.
Rapid Control Methods:
If direct pressure is insufficient, rapid application of vascular clamps or intraluminal occlusion devices is paramount
Consider placing vascular tape around the IVC for temporary control.
Damage Control Surgery:
In severe trauma with uncontrolled haemorrhage, damage control principles apply, which may involve temporary packing and leaving the abdomen open, with definitive control at a later stage.
Adjunctive Haemostasis:
Use of topical haemostatic agents (e.g., oxidized regenerated cellulose, gelatin sponges, fibrin sealants) may be helpful for oozing from the dissection bed or hepatic parenchyma.
Complications
Early Complications:
Massive haemorrhage from IVC injury
hepatic ischaemia and necrosis from prolonged occlusion or inadequate venous outflow
acute kidney injury due to impaired renal venous drainage
bleeding from other intra-abdominal structures.
Late Complications:
Hepatic dysfunction
caval stenosis or thrombosis
post-caval syndrome
pulmonary embolism
re-bleeding.
Prevention Strategies:
Thorough anatomical knowledge and preoperative imaging
meticulous dissection technique
judicious use of Pringle manoeuvre
adequate blood product support
timely and effective control of bleeding
careful postoperative monitoring.
Key Points
Exam Focus:
Understanding the anatomical landmarks of the retrohepatic IVC, its tributaries, and the surgical planes for safe dissection
Knowledge of indications and contraindications for different control techniques.
Clinical Pearls:
Always confirm adequate haemostasis before closing the abdomen
Be prepared for massive blood loss
have your blood bank on standby
Remember the right hepatic vein drains directly into the IVC and is often the largest tributary.
Common Mistakes:
Aggressive dissection without clear visualization of the IVC wall
failure to anticipate bleeding
inadequate mobilization leading to difficult clamp application
mistaking the common hepatic vein for a caval tributary
prolonged IVC occlusion leading to organ ischaemia.