This rSO2 study is a prospective clinical study. The purpose of the rSO2 study is to investigate whether there is a correlation between the intraoperative cerebral and renal tissue oxygen saturation and the incidence of developmental and socioemotional delay after living donor liver transplantation for children. This study will also investigate whether intraoperative cerebral and renal tissue oxygen saturation are related to postoperative complications.

There is high incidence of developmental and socioemotional delay and postoperative complications in pediatric living donor liver transplantation patients. In this prospective observational clinical study, the investigators aim to investigate the correlation between the intraoperative cerebral and renal tissue oxygen saturation and the incidence of developmental and socioemotional delay and postoperative complications. This study will enroll patients aged from 6 to 36 months old who are scheduled for elective standard living-donor liver transplantation and have signed informed consent before the surgery.

Inclusion Criteria:

• Pediatric patients (6 months< the Moon's age <36 months) who will receive standard living-donor liver transplantation (LDLT) in Renji Hospital.

Exclusion Criteria:

• Forehead skin infection, A history of liver transplantation, Multivisceral transplantation, Refused to participate the study

This study will enroll patients aged from 6 to 36 months old who are scheduled for elective standard living-donor liver transplantation and have signed informed consent before the surgery.