This is an observational study examining serum markers in patients who are undergoing either a cadaveric liver transplant or a living related liver transplant.

The Departments of Anesthesiology are conducting an observational trial of markers in the serum of patients who are undergoing liver transplantation surgery. This study will utilize the biological markers, trimethylamine-N-oxide (TMAO), NGAL, and cystatin-C, sensitive markers of renal medullary injury in the blood and allantoin, a marker of oxidative stress as indicators of renal injury in a kidney during liver transplants. It is hypothesized that: (1) these markers are less pronounced in living donor liver transplant recipient patients than in cadaveric liver transplant recipients, and (2) these markers are less pronounced in cadaveric liver transplant recipients in which a "piggy-back" technique was used versus recipients in which a total venous occlusion technique was used. This study will be done in a multi-center format, along with researchers at UCSF

Inclusion Criteria:

• American Society of Anesthesiologists (ASA) Class I-V.
• Patient is undergoing elective Liver Transplant Surgery.
• Patient is an adult, 18 years old or older.

Exclusion Criteria:

• Patients < 18 Years of Age
• Patients who are pregnant

Subjects will be recruited from those on the list awaiting liver transplantation at Vanderbilt University Medical Center (VUMC). They will be recruited by the investigators prior to the time of their transplantation surgery