Liver transplantation

Indications & Contraindications - The Transplant Gates

• Indications (Who gets a new liver?)

  • Acute Liver Failure (e.g., fulminant hepatitis).
  • Chronic Liver Disease/Cirrhosis with decompensation (ascites, encephalopathy, variceal bleeds).
  • Hepatocellular Carcinoma (HCC) meeting specific criteria.
  • Certain metabolic diseases (e.g., Wilson's disease).

• Contraindications (Who doesn't?)

  • Absolute: Severe cardiopulmonary disease, active extrahepatic malignancy, uncontrolled sepsis, active substance abuse.
  • Relative: Morbid obesity, poor psychosocial support, non-adherence.

⭐ Milan Criteria for HCC: Solitary tumor ≤ 5 cm, or up to 3 tumors each ≤ 3 cm, with no extrahepatic spread or major vascular invasion.

Pre-transplant Evaluation - The MELD Meter

• MELD Score (Model for End-Stage Liver Disease): Objectively predicts 3-month mortality risk in patients with cirrhosis to guide organ allocation.
• Core Components:
  • Total Bilirubin
  • International Normalized Ratio (INR)
  • Creatinine
  • Serum Sodium (in MELD-Na variant)
• 📌 Mnemonic: I Crush Beer Smoothly (INR, Creatinine, Bilirubin, Sodium).
• Scoring: Ranges from 6 (less ill) to 40 (gravely ill). A higher score indicates a greater urgency for transplantation.

⭐ MELD Exceptions: Patients with conditions like Hepatocellular Carcinoma (HCC) receive standardized MELD "exception points" to ensure equitable access to transplant, as their lab-based MELD score may not fully reflect their mortality risk.

Surgery & Donors - The Great Liver Swap

• Donors: Deceased (DDLT) or living-donor (LDLT). Split-liver technique can create two grafts from one donor liver.
• Surgical Technique:
  • Classical: Total hepatectomy with IVC resection.
  • Piggyback: Preserves recipient IVC, reducing hemodynamic instability.
  • Anastomosis Order: Suprahepatic IVC, infrahepatic IVC, portal vein, hepatic artery, then biliary duct.

⭐ High-Yield: The hepatic artery is the most common site of post-transplant thrombosis, often leading to graft failure.

Post-Op Management - Bugs, Drugs & Rejection

• Infection Timeline:

  • <1 Month: Bacterial (nosocomial, line-related), Candida, HSV.
  • 1-6 Months: Opportunistic pathogens. Key threats are Cytomegalovirus (CMV), Pneumocystis jirovecii (PJP), and Aspergillus.
  • >6 Months: Standard community-acquired pathogens.

• Core Immunosuppression:

  • Calcineurin Inhibitor (CNI): Tacrolimus (mainstay).
  • Antimetabolite: Mycophenolate Mofetil (MMF).
  • Corticosteroids: Prednisone (tapered).

• Rejection:

  • Acute Cellular (ACR): T-cell mediated, common in first few months. Presents with ↑LFTs. Dx: Biopsy. Tx: Steroid bolus.
  • Chronic: Late (>1 yr), ductopenic rejection (vanishing bile duct syndrome). Leads to graft failure.

⭐ CMV is a major cause of allograft dysfunction and morbidity in the 1-6 month window. Prophylaxis (e.g., Valganciclovir) is standard for at-risk patients.

• The MELD score (Bilirubin, INR, Creatinine) is paramount for organ allocation, predicting 3-month mortality.
• Primary indications include decompensated cirrhosis (ascites, encephalopathy, variceal bleeding) and hepatocellular carcinoma within Milan criteria.
• Key absolute contraindications are severe cardiopulmonary disease, extrahepatic malignancy, and active substance abuse.
• Post-transplant immunosuppression typically involves tacrolimus, mycophenolate, and corticosteroids.
• Hepatic artery thrombosis is the most devastating early vascular complication.
• Acute cellular rejection is T-cell mediated; treat with high-dose steroids.