Overview

Definition:
-The hepatectomy phase of liver transplantation refers to the critical surgical period where the diseased native liver (or explant) is removed from the recipient, and the graft liver is prepared for implantation
-This phase is marked by meticulous dissection, control of major vascular and biliary structures, and management of potential bleeding and hemodynamic instability.
Epidemiology:
-Liver transplantation is performed for end-stage liver disease (ESLD) from various etiologies including cirrhosis (alcoholic, viral hepatitis, NASH), hepatocellular carcinoma (HCC), and acute liver failure
-The demand for liver transplants consistently outstrips the availability of donor organs, making efficient and safe surgical execution paramount.
Clinical Significance:
-This phase is arguably the most technically demanding and hemodynamically challenging part of a liver transplant
-Mastery of recipient hepatectomy directly impacts patient outcomes, minimizes operative morbidity and mortality, and reduces the incidence of early graft dysfunction
-It is a core competency for transplant surgeons preparing for DNB and NEET SS examinations.

Indications For Transplant

Esld Criteria:
-MELD score of 15 or higher for cirrhosis
-Specific criteria for alcoholic hepatitis, NASH cirrhosis, and primary biliary cholangitis
-Contraindications include uncorrected coagulopathy, active sepsis, and severe cardiopulmonary disease.
HCC Criteria:
-Milan criteria (single lesion <= 5 cm or up to 3 lesions each <= 3 cm)
-Expanded criteria based on downstaging and specific tumor biology
-Importance of multidisciplinary tumor board review.
Acute Liver Failure:
-Indications include coagulopathy (INR > 1.5 unresponsive to vitamin K) and hepatic encephalopathy in the absence of pre-existing liver disease
-Consideration for hyperacute, acute, and subacute forms.

Preoperative Assessment And Preparation

Patient Evaluation:
-Comprehensive assessment of comorbidities: cardiac, pulmonary, renal, and endocrine function
-Nutritional status evaluation
-Infectious disease screening (CMV, EBV, Hepatitis viruses).
Donor Liver Evaluation:
-Assessment of donor liver quality: steatosis, steatohepatitis, size matching, cold ischemic time
-Use of machine perfusion techniques to assess graft viability.
Anesthesia Considerations:
-Advanced hemodynamic monitoring: arterial lines, central venous catheters, pulmonary artery catheter (if indicated)
-Management of coagulopathy and thrombocytopenia
-Fluid management strategies and blood product availability.

Recipient Hepatectomy Technique

Surgical Approach:
-Standard subcostal or Mercedes-Benz incision for optimal exposure
-Careful dissection of the falciform ligament and round ligament
-Identification and preservation of the infrahepatic inferior vena cava (IVC).
Vascular Dissection And Control:
-Mobilization and control of the suprahepatic and infrahepatic IVC
-Careful dissection and ligation of hepatic veins draining into the IVC
-Identification and isolation of the portal vein and hepatic artery
-Control of these vessels is crucial to minimize blood loss.
Biliary Dissection And Explantation:
-Dissection of the common hepatic duct or common bile duct
-Division of the bile duct
-Careful inspection for accessory ducts or anomalies
-Careful dissection around the porta hepatis to avoid injury to surrounding structures.
Explantation And Hemostasis:
-Systematic removal of the native liver, meticulously controlling bleeding from the raw liver surfaces and from the caval stumps
-Use of topical hemostatic agents and meticulous suture ligation
-Management of potential torrential bleeding from caval lacerations or hepatic vein avulsions.

Intraoperative Management And Challenges

Hemodynamic Instability:
-Frequent fluid shifts, vasopressor requirements, and potential for distributive shock
-Aggressive fluid resuscitation and judicious use of vasoactive agents
-Rapid blood product replacement (RBCs, FFP, platelets, cryoprecipitate) based on thromboelastography (TEG) or rotational thromboelastometry (ROTEM).
Bleeding Management:
-High risk of torrential hemorrhage due to portal hypertension, coagulopathy, and the friable nature of the diseased liver
-Use of intraoperative cell salvage
-Identification and management of accessory hepatic arteries and veins
-Potential need for temporary caval shunting.
Ischemia Reperfusion Injury:
-This occurs during the reperfusion of the graft
-Strategies to minimize include early reperfusion, meticulous graft preparation, and judicious use of crystalloids and colloids
-Monitoring for signs of early graft dysfunction.

Post Hepatectomy Care And Graft Reperfusion

Graft Preparation:
-Once explanted, the graft liver is prepared for implantation
-This involves trimming and vascular anastomoses
-The hepatectomy phase concludes with the final steps of explant removal and initial steps of graft preparation.
Initial Reperfusion:
-The moment the vascular clamps are released on the newly anastomosed portal vein and hepatic artery
-This is followed by reperfusion of the IVC, and then the hepatic veins
-Close monitoring of blood pressure, heart rate, and graft appearance (color, turgor).

Complications Of Hepatectomy

Hemorrhage:
-Major bleeding from vascular structures, raw liver surface, or caval lacerations
-Requires aggressive resuscitation and prompt surgical re-exploration if uncontrolled.
Hemodynamic Collapse:
-Profound hypotension and shock due to massive blood loss, vasodilation, and reperfusion injury
-Requires aggressive management with fluids, vasopressors, and blood products.
Caval Injury:
-Lacerations to the infrahepatic or suprahepatic vena cava can lead to catastrophic bleeding
-Meticulous dissection and prompt repair are essential
-Temporary caval shunting may be required.
Bile Duct Injury:
-Though more common during the anastomosis phase, inadvertent injury during hepatectomy can occur
-Careful identification and preservation of the bile duct are paramount.

Key Points

Exam Focus:
-Critical structures to identify and control during hepatectomy: IVC (supra/infrahepatic), portal vein, hepatic artery, hepatic veins
-Understanding hemodynamic management strategies
-Recognizing and managing torrential bleeding
-The concept of caval shunting.
Clinical Pearls:
-Maintain meticulous dissection planes to minimize bleeding
-Have blood products and cell saver ready
-Aggressively manage hemodynamic instability with a low threshold for vasopressors
-Think about outflow obstruction from hepatic vein confluence
-Communicate continuously with the anesthesia team.
Common Mistakes:
-Inadequate control of vascular structures before division
-Underestimation of blood loss and delayed resuscitation
-Failure to recognize and manage caval injuries promptly
-Insufficient attention to hemodynamic monitoring and fluid management
-Poor visualization leading to injury of surrounding structures.