Intraoperative Normal Saline Administration and Acute Kidney Injury in Patients Undergoing Liver Transplantation

Study Overview
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Brief Summary
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The investigators attempted to investigate the association of the type of crystalloid administered during liver transplantation with postoperative clinical outcomes. The investigators hypothesized that the greater amount of normal saline or half-saline administered during liver transplantation might be associated with the increased risk of acute kidney injury compared to the balanced crystalloids.

Detailed Description
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Liver transplantation requires a long operation time and is often associated with a significant amount of surgical bleeding. It is common for the anesthesiologist to infuse large amounts of fluid or blood products due to bleeding, hemodynamic instability, or ascites drainage. Therefore, in the anesthesia for liver transplantation, optimal management of fluid administration is necessary and the choice of the type of crystalloid may affect the prognosis or the incidence of postoperative complications of patients. The investigators attempted to investigate the association of the type of crystalloid administered during liver transplantation with postoperative clinical outcomes. The investigators hypothesized that the greater amount of normal saline or half-saline administered during liver transplantation might be associated with the increased risk of acute kidney injury compared to the balanced crystalloids.

Official Title
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Intraoperative Normal Saline Administration and Acute Kidney Injury in Patients Undergoing Liver Transplantation: a Retrospective Cohort Study

Conditions
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End Stage Liver DIsease, Liver Transplant; Complications, Liver Cirrhosis

Intervention / Treatment
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* Drug: Normal saline
* Drug: Balanced crystalloid solution


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Consecutive patients who underwent living or deceased donor liver transplantation at our tertiary care university hospital between 2004 and 2018 Exclusion Criteria: patients with baseline renal dysfunction of hepatorenal syndrome or chronic kidney disease missing preoperative serum creatinine value missing other baseline or outcome variables patients who received retransplantation

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Balanced group<br>Patients who received balanced crystalloids of lactated Ringer's solution or plasma solution during liver transplantation surgery | Drug: Balanced crystalloid solution<br>* Patients received balanced crystalloids such as lactated Ringer's solution or Plasma solution as a maintenance crystalloid during liver transplantation surgery.<br>* Other names: Plasma solution;|
| Saline group<br>Patients who received only normal saline during liver transplantation surgery | Drug: Normal saline<br>* Patients received normal saline as a maintenance crystalloid during liver transplantation surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute kidney injury | The investigators defined acute kidney injury by the KDIGO (Kidney Disease Improving Global Outcomes) criteria, which was determined according to the greatest change in serum creatinine level during the postoperative seven days (Stage 1: more than 1.5-fold; stage 2: more than 2-fold; stage 3: more than 3-fold increase of baseline or increase in SCr to ≥ 4.0 mg/dL or the initiation of renal replacement therapy). The most recent SCr level measured before surgery was collected as a baseline value. | the first 7 postoperative days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of postoperative hemodialysis | the incidence of new-onset postoperative hemodialysis during hospitalization | the first month after admission | 
| Early allograft dysfunction | One or more of the following are present within the first 7 postoperative days: total bilirubin ≥ 10 mg/dL, PT (prothrombin time):INR (international normalized ratio)≥ 1.6, or AST (aspartate aminotransferase)/ALT (alanine aminotransferase) > 2000 IU/L | the first 7 postoperative days | 
| In-hospital mortality | all-cause mortality during hospitalization | the first month after admission | 
| One-year mortality | all-cause mortality during one year after transplantation | one year after transplantation | 
| Length of intensive care unit stay | Length of intensive care unit stay after transplantation | the first month after admission | 
| Length of hospital stay | Length of hospital stay after transplantation | the first month after admission |