Renal and Cardiac Risk Factors of AKI After Liver Transplantation

Study Overview
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Brief Summary
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Background: Liver transplantation (LT) is an extensive operation with various factors contributing to the development of acute kidney injury in the perioperative period. Early diagnosis of AKI can improve clinical outcomes in LT recipients. Renal resistive index is measured in renal arteries and high resistive values are associated with more adverse cardiovascular events and renal failure progression. Myocardial performance index reflects overall cardiac function rather than systolic or diastolic function alone. Aim of the study: to investigate whether combined doppler renal resistive index and myocardial performance index could predict early postoperative acute kidney injury in living donor liver transplant recipients. Study design: a prospective observational study that will be conducted at Liver Transplantation Unit at Mansoura University on 105 consecutive living donor liver transplant recipients. Methods: Renal resistive index (assessed by transabdominal ultrasound) and myocardial performance index (assessed by transthoracic echocardiography) will be measured just before operation, on termination of operation and then daily in the intensive care unit for 7 days. Patients will be observed for development of acute kidney injury.

Detailed Description
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This study aims to investigate whether combined doppler renal resistive index (RRI) assessed by transabdominal sonography and myocardial performance index (MPI) assessed by transthoracic echocardiography could predict early postoperative acute kidney injury in living donor liver transplant recipients. The primary outcome is the predictive value of renal resistive index and myocardial performance index for the onset of early post living donor liver transplant acute kidney injury. This prospective observational study will be conducted at Liver Transplantation Unit at Mansoura University from November 2022 till fulfillment of sample size after obtaining approval from Institutional Review Board (IRB). One hundred and five consecutive LDLT recipients will participate in this study after obtaining informed consents. They will be observed for the development of early postoperative acute kidney injury.

Official Title
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Renal Resistive Index and Myocardial Performance Index for Early Prediction of Acute Kidney Injury After Living Donor Liver Transplantation

Conditions
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Acute Kidney Injury, Acute Renal Injury, Liver Transplant; Complications

Intervention / Treatment
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* Diagnostic Test: renal resistive index and myocardial performance index


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing right-lobe living-donor liver transplantation Exclusion Criteria: preoperative renal impairment (GFR < 60 ml/min/1.73 m2) known renal artery stenosis patient who underwent previous nephrectomy ischemic heart disease (patient who takes anti-ischemic measures as prescribed by a consultant cardiologist) Patient with arrthymia or who develop persistent intraoperative arrythmia

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: renal resistive index and myocardial performance index|Transthoracic echocardiography and transabdominal ultrasonography will be performed before induction of anesthesia, after termination of operation and before transmission to ICU and then daily for the early seven postoperative days. RRI = (peak systolic velocity - end diastolic velocity) ∕ peak systolic velocity: Then, we will obtain the mean RRI from the above three measurements. We will consider RRI ≥0.7 as abnormal and define it as subclinical AKI. Myocardial performance index (using tissue doppler) = (isovolumetric contraction time + isovolumetric relaxation time) / ejection time. We will consider MPI ≥0.4 as abnormal and define it as subclinical LV dysfunction.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| early acute kidney injury (AKI) | international Club of Ascites' revised classification of AKI in cirrhotic patients as a 0.3 mg/kg increase in serum creatinine | in the early 48 postoperative hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| stage of AKI | Stage (1): serum creatinine increase 1.5- 1.9 times base line; or serum creatinine increase more than 0.3mg/dl. Stage (2): serum creat. Increase 2-2.9 times baseline. Stage (3): serum creat. Increase 3 times baseline ; or s.creat increase to 4mg/dl; or initiation of renal replacement therapy. | in the early 48 postoperative hours | 
| late AKI | International Club of Ascites' revised classification of AKI in cirrhotic patients as a 0.3 mg/kg increase in serum creatinine or >= 50% increase in the basal serum creatinine | within 7 days | 
| length of ICU stay | duration of ICU stay (days) in survived patients | 3 months after transplant | 
| length of hospital stay | duration of ICU stay (days) in survived patients | 3 months after transplant | 
| three-month mortality | all-cause mortality | 3 months after transplantation | 
| delayed renal function | serum creatinine | 3 months after transplantation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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2-D Echocardiography, Two-Dimensional Echocardiography, renal resistive index, myocardial performance index, diagnostie test accuracy, sensitivity and specificity