Association of Intraoperative Renal Regional Oxygen Saturation and Acute Kidney Injury

Study Overview
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Brief Summary
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This study is a prospective observational study of a single cohort of the patients who will undergo a scheduled living donor liver transplantation. The investigators attempt to evaluate the association of intraoperative renal regional oxygen saturation and acute kidney injury in patients undergoing living donor liver transplantation. Near-infrared spectroscopy sensor will be attached to the skin near bilateral kidney areas in all patients and renal regional oxygen saturation will be monitored during the operation. Renal regional oxygen saturation (rSO2) of the patients who developed acute kidney injury postoperatively will be compared with rSO2 of the patients who did not.

Detailed Description
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Acute kidney injury is a frequent complication after liver transplantation, which is related to poor prognosis and longer hospital stay. There is no sensitive or specific marker for predicting postoperative acute kidney injury, although studies of the biomarkers have shown promising results. Near-infrared spectroscopy is a non-invasive and real-time monitoring device for regional oxygen saturation measurement. Previous studies revealed that it could be applied to the skin near the kidney and be used to monitor renal regional oxygen saturation. Therefore, in this study, the investigators will apply near-infrared spectroscopy around kidney area to measure real-time renal regional oxygen saturation during liver transplantation surgery and investigate the association between the intraoperative renal regional oxygen saturation and the development of post-transplant acute kidney injury.

Official Title
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Association of Intraoperative Renal Regional Oxygen Saturation and Acute Kidney Injury After Living Donor Liver Transplantation

Conditions
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Liver Transplant; Complications, Renal Injury

Intervention / Treatment
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* Device: Near-infrared spectroscopy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients scheduled to undergo elective living donor liver transplantation Patients who provided written informed consent Exclusion Criteria: Missing preoperative serum creatinine value Underlying kidney disease, such as hepatorenal syndrome, chronic kidney disease History of unilateral or bilateral nephrectomy Patients who died within 48 hours immediately after surgery Any skin problem at the attachment site of regional oxygen saturation probe

Ages Eligible for Study
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Minimum Age: 20 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Interventional Model Description: A prospective, single group, observational study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Regional oxygen saturation group<br>Near-infrared spectroscopy application to the skin near the kidney | Device: Near-infrared spectroscopy<br>* Regional oxygen saturation probe is applied to the skin near the kidney bilaterally and is connected to the regional oxygen saturation monitor.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute Kidney Injury | Acute kidney injury defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria using postoperative serum creatinine | Within 7 days after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of hospital stay | Length of hospital stay | Within 30 days after surgery | 
| Nadir oxygen delivery during the surgery | Nadir oxygen delivery calculated by the cardiac output and arterial oxygen content | Within average 8 hours after anesthesia induction during the transplantation surgery | 
| Area under the curve of oxygen delivery during the surgery | Area under the curve of oxygen delivery calculated by the cardiac output and arterial oxygen content | Within average 8 hours after anesthesia induction during the transplantation surgery | 
| Early allograft dysfunction | Early allograft dysfunction diagnosed by one or more of the following variables: (1) bilirubin > 10 mg/dL on postoperative day 7; (2) prothrombin time: international normalized ratio > 1.6 on postoperative day 7; (3) aminotransferase level (alanine aminotransferase or aspartate aminotransferase > 2000 IU/ml within the first 7 postoperative days. | on the postoperative 7th day after liver transplantation | 
| In-hospital mortality | In-hospital mortality | Within 30 days after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Near-infrared spectroscopy, Renal regional oxygen saturation, Living donor liver transplantation, Acute kidney injury