The Impact of Vitamin C on Postoperative Acute Kidney Injury in Risk Patients Undergoing Valvular Heart Surgery

Study Overview
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Brief Summary
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In cases of cardiac surgery or sepsis which cause inflammation, oxidative stress, endothelial injury and vasoplegia, serum vitamin C concentration is sharply decreased. The anti-inflammatory and anti-oxidant effects of vitamin C and the effects of reducing vasoconstrictor use have been demonstrated in patients with sepsis and septic shock, however, the foregoing effects have not been validated in patients undergoing cardiac surgery. In this study, investigators investigate the effect of intravenous vitamin C on the incidence of acute renal injury after valvular heart surgery.

Official Title
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The Impact of Vitamin C on Postoperative Acute Kidney Injury in Risk Patients Undergoing Valvular Heart Surgery

Conditions
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Acute Kidney Injury

Intervention / Treatment
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* Drug: Vitamin C
* Drug: Control (Normal saline)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients older than 20 years and undergoing elective valvular heart surgery whose preoperative acute renal failure score is ≥3 (moderate to severe risk). Exclusion Criteria: Emergency operation Cardiogenic shock or ventricular-assist device (eg. ECMO, IABP) Severe chronic kidney disease (GFR(CKD-EPI) <30ml/min/1.73m2) Patients with past history of gout or renal stone or hyperoxaluria or cystinuria Hemolytic anemia due to pyruvate kinase deficiency or glucose-6-phosphate dehydrogenase deficiency Sicklemia or thalassemia Hemochromatosis Allergy to disodium ethylenediamine-tetraacetate or ascorbic acid Patients taking aspirin up to 3 days before surgery Patients taking antiepileptic drug or fluphenazine or steroid Patients taking vitamin C within a month of surgery Pregnant or lactating women Patients who cannot understand the informed consent (eg. Foreigner)

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
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Patients are divided into 2 groups, who are administered IV Vitamin C or who are administered IV normal saline.
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Control group<br>Participants in this group are administered IV normal saline. | Drug: Control (Normal saline)<br>* Participants in Control group are administered IV 100cc normal saline at the same timepoint as above.<br>|
| Experimental: Vitamin C group<br>Participants in this group are administered IV vitamin C diluted in normal saline. | Drug: Vitamin C<br>* Participants in Vitamin C group are administered IV vitamin C diluted in 100 cc normal saline 1 day before surgery, at rewarming during surgery, 3 hours after surgery, and every 6 hours thereafter until postoperative 24 hours.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative acute kidney injury | Compare the incidence of postoperative acute kidney injury between the Vitamin C group and the control group according to KDIGO guideline. | Postoperative 7 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative oxidative stress and vascular injury(Comparing the serum concentration) | Compare the serum concentration of Malondialdehyde, Thrombomodulin before anesthetic induction and after CPB cessation. | Before anesthetic induction (Baseline) | 
| Postoperative oxidative stress and vascular injury(Comparing the serum concentration) | Compare the serum concentration of Malondialdehyde, Thrombomodulin before anesthetic induction and after CPB cessation. | 5 minute after CPB cessation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Postoperative acute kidney injury