Influence of Preoperative Fluid Intake on the Onset of Postoperative Acute Kidney Injury

Study Overview
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Brief Summary
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To investigate the influence of preoperative fluid and food intake in cardiac surgery patients on the development of postoperative AKI.

Detailed Description
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Acute renal failure (ARF) and the need for renal replacement therapy (RRT) is a major complication after cardiac surgery, associated with mortality and an increased risk to develop end-stage renal disease. Cardiac surgery patients are at increased risk to develop acute kidney failure due to ischaemia-reperfusion injury, cardiopulmonary bypass (CPB) induced inflammation and haemolysis, hemodynamic alterations, vasoconstriction and resulting reduced renal perfusion. According to the current literature, AKI occurs in average in 20-30% after cardiac surgery with an incidence of RRT in 1-5%. Several reviews revealed the literature and concluded that , inter alia, euvolemia, adequate nutrition, the avoidance of nephrotoxic drugs and anemia optimization belong to the most effective prevention strategies. Patients are instructed to follow the nil per os (NPO) guidelines, including abstinence of clear liquids for >2 hours preoperative as well as fasting time of light foods for > 6 hours and fatty foods for >8 hours prior to surgery. However, these guidelines encourage patients to continue PO hydration until 2 h before surgery in order to optimize the volume status. Besides the fact that NPO lasts in average critically longer than required, surgery delay is a common issue and may lead to an exceedance of NPO up to twice as long as required. Data about the exact mechanism is still sparse, but preoperative iv hydration may correct or even expand intravascular volume, improve renal perfusion and induce diuresis, stimulate endogenous natriuretic peptides release and inactivate the renin-angiotensin-aldosterone system (RAAS). Large trials on this very relevant topic in these high risk cardiac surgery patients are absolutely missing. Therefore, this prospective observational study aims to investigate the influence of varied preoperative fluid and food intake in cardiac surgery patients on the development of postoperative AKI.

Official Title
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Influence of Preoperative Fluid Intake on the Onset of Postoperative Acute Kidney Injury in Cardiac Surgery Patients: the HYDRATE-CSX Trial

Conditions
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Thoracic Surgery, Acute Kidney Injury, Critical Care

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients (>18 years of age) scheduled to undergo elective cardiac surgery with the use of cardiopulmonary bypass (CPB) and cardioplegic arrest Exclusion Criteria: Patients not willing to participate or not able to give informed consent Patients receiving contrast agents within 72 hours before surgery Patients with preoperative need for renal replacement therapy Patients receiving an extracorporeal mechanical assist device (e.g. ECLS) or for advanced heart failure therapies (e.g. TAH, VAD) will be excluded. Patients participating in another interventional trial Pregnant or lactating patients

Ages Eligible for Study
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Minimum Age: 18 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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute kidney injury | Acute kidney injury | 30 days | 
| Renal replacement therapy | Renal replacement therapy | 7 days postoperative | 
| Kidney-failure-free days | defined as the number of days in which a patient had no acute kidney injury and no need for RRT | 7 days postoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Major Adverse Kidney Events | death, dialysis or persistent renal dysfunction | 30 days | 
| Fluid intake since hospital admission until surgery (ml/h) | Fluid intake since hospital admission until surgery (ml/h) | 30 days | 
| Calorie intake since hospital admission (kcal/d) | Calorie intake since hospital admission (kcal/d) | 30 days | 
| Preoperative abstinence of fluids (minutes) | Preoperative abstinence of fluids (minutes) | 30 days | 
| Preoperative abstinence of food (minutes) | Preoperative abstinence of food (minutes) | 30 days | 
| ICU length of stay (hours) | ICU length of stay (hours) | 30 days | 
| Hospital length of stay since surgery (days) | Hospital length of stay since surgery (days) | 30 days | 
| Mortality until hospital discharge/ 30 days | Mortality until hospital discharge/ 30 days | up to 30 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cardiac surgery patients, acute renal failure, intensive care