Living donor liver transplant (LDLT) is an advanced surgical intervention in hepatobiliary and transplant surgery designed to cure end-stage liver disease, acute liver failure, and selected primary liver malignancies. The fundamental goal of LDLT is to replace a non-functioning liver with a healthy partial liver graft from a living human donor. Because the human liver possesses remarkable capacity for regeneration (the regrowth of lost organ tissue through cellular proliferation), both the donor's remaining liver and the recipient's newly implanted partial graft grow back to normal functional mass within 8 to 12 weeks post-surgery (AASLD 2023 Guidelines). This procedure significantly alleviates organ shortages, allows for elective scheduling before severe recipient decompensation, and lowers overall mortality rates on liver transplant waiting lists.

Living donor liver transplantation requires dual synchronized operations. In the donor room, surgeons perform a partial hepatectomy, usually taking the right hepatic lobe (segments V-VIII) for adult recipients or the left lateral segment (segments II and III) for pediatric recipients. The graft is flushed with cold preservation solution. Simultaneously, in the recipient room, the diseased liver is mobilized and explanted while preserving the recipient's inferior vena cava, portal vein, and hepatic artery. The donor graft is placed into the abdominal cavity. Micro-vascular anastomoses are performed sequentially: hepatic vein to recipient hepatic vein/IVC, portal vein to recipient portal vein, and hepatic artery to recipient hepatic artery using surgical loupes or operating microscopes. Biliary continuity is established using either a duct-to-duct anastomosis or a Roux-en-Y choledochojejunostomy. Hemostasis is verified, drains are placed, and incisions are closed.

Living donor liver transplant offers crucial clinical advantages over traditional deceased donor liver transplant (DDLT):

• Reduced Waitlist Mortality: Patients receive a life-saving organ before experiencing progressive clinical decompensation, organ failure, or removal from the waiting list due to death or severe systemic decline.
• Optimized Organ Quality: Grafts are derived from healthy, extensively screened living individuals, minimizing cold ischemia time (time organ is stored on ice) to usually under two hours.
• Elective Surgical Timing: Surgery is scheduled in advance under controlled conditions, avoiding emergency operations in hemodynamically unstable patients.
• Superior Short-term Outcomes: Reduced incidence of delayed graft function and primary non-function compared to high-risk extended criteria deceased donor organs (ASTS 2021 Guidelines).
• Favorable Tumor Control: For patients with hepatocellular carcinoma, timely transplantation prevents disease progression outside established transplant eligibility windows.

Recovery from living donor liver transplant follows distinct donor and recipient protocols:

Donor Recovery Timeline

• Days 1–2: ICU or high-dependency unit monitoring, early mobilization, multimodal intravenous pain control.
• Days 3–7: Transition to oral analgesics, dietary advancement to regular food, discharge planning once biological function and liver enzymes normalize.
• Weeks 2–6: Progressive home mobility, avoidance of heavy lifting (>5 kg), monitoring incision healing.
• Months 2–3: Volumetric liver growth reaches 85–90% capacity; return to full light-to-moderate occupational work.
• Months 6: Complete physiological recovery and full physical activity clearance.

Recipient Recovery Timeline

• Days 1–3: Intensive care management, mechanical extubation, continuous portal venous flow Doppler ultrasound, initiation of immunosuppressive therapy.
• Days 4–14: Inpatient floor recovery, monitoring therapeutic drug levels (e.g., tacrolimus), physical therapy mobilization, surgical drain removal.
• Months 1–3: Outpatient clinic visits twice weekly, blood laboratory monitoring, graft size enlargement, physical rebuilding.
• Months 4–6: Reduction of acute immunosuppression dosage, return to light daily tasks, transition to monthly laboratory monitoring.
• Year 1 and Beyond: Stable lifelong maintenance immunosuppression, regular transplant clinic reviews, monitoring for chronic rejection or late biliary strictures.

Living donor liver transplant is indicated for severe liver disorders that severely impair metabolic, synthetic, or excretory function. Conditions treated include:

• Decompensated Cirrhosis: Advanced liver scarring secondary to chronic hepatitis B or C, non-alcoholic steatohepatitis (NASH/MASH), or alcoholic liver disease.
• Hepatocellular Carcinoma (HCC): Primary liver cancer meeting specific selection criteria (such as Milan or UCSF criteria) to ensure acceptable post-transplant survival.
• Acute Liver Failure: Rapid destruction of functional liver tissue from viral hepatitis, drug toxicity, or autoimmune hepatitis.
• Cholestatic Liver Diseases: Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) leading to end-stage biliary cirrhosis.
• Inborn Errors of Metabolism: Genetic diseases including Wilson disease, alpha-1 antitrypsin deficiency, and glycogen storage diseases where the liver lacks vital metabolic enzymes.
• Pediatric Liver Diseases: Biliary atresia, progressive familial intrahepatic cholestasis (PFIC), and metabolic disorders in infants and young children.

Donor preparation includes extensive volumetric triple-phase CT angiography, magnetic resonance cholangiopancreatography (MRCP), cardiac stress testing, psychological screening, and complete laboratory workups. If hepatic steatosis (fatty liver) is suspected, a liver biopsy is performed to confirm <10-15% macrovesicular steatosis. The donor must cease oral contraceptives or nicotine products at least 4-6 weeks prior to surgery. Recipient preparation involves cardiac clearance, pulmonary function testing, clearing infectious foci, maintaining nutritional support, and undergoing updated anatomical scanning. Both patients receive prophylactic antibiotics and perioperative blood product planning.

Donor risks include bile leakage (3-7%), wound infection, deep vein thrombosis, pulmonary embolism, pleural effusion, bowel obstruction, and a low mortality risk estimated at 0.2-0.5% for right lobe donation. Recipient risks include hepatic artery thrombosis (2-5%), portal vein thrombosis, primary graft non-function, small-for-size syndrome, biliary stricture or leak (15-25%), acute rejection (10-20%), opportunistic systemic infections, chronic immunosuppressive side effects (nephrotoxicity, diabetes, hypertension), and graft loss requiring re-transplantation.

The journey through a living donor liver transplant involves distinct clinical phases for both donor and recipient.

Phase 1: Pre-Transplant Evaluation and Matching

Both donor and recipient undergo comprehensive medical, anatomical, immunologic, and psychosocial testing. Donors undergo triple-phase computed tomography angiography (a detailed 3D blood vessel scan) and magnetic resonance cholangiopancreatography to verify vascular and biliary anatomy suitability. Recipients undergo rigorous cardiovascular, pulmonary, and oncologic staging.

Phase 2: The Surgical Procedure

Performed concurrently in adjacent operating suites, surgical teams harvest the graft from the donor while preparing the recipient via total hepatectomy (surgical removal of the diseased liver). Vascular connections (hepatic vein, portal vein, hepatic artery) and biliary connections are meticulously re-established under surgical microscopic visualization.

Phase 3: Acute Hospital Recovery

The donor typically spends 5 to 7 days in the hospital, starting in intensive care before transitioning to a step-down unit. The recipient spends 10 to 14 days in the hospital, requiring initial mechanical ventilation and intensive hemodynamic monitoring in the intensive care unit (ICU) followed by immunosuppression adjustment.

Phase 4: Long-Term Follow-up and Rehabilitation

The recipient requires lifelong surveillance and immunosuppression (medication that prevents organ rejection). Routine blood tests, ultrasound imaging, and clinical assessments ensure optimal graft performance and monitor for potential rejection or infection.