Limiting IV Chloride to Reduce AKI After Cardiac Surgery

Study Overview
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Brief Summary
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This primary aim of this study is to test the impact of a strategy of perioperative chloride-restriction through intravenous (IV) fluid therapy on the incidence of acute kidney injury after cardiac surgery. A prospective, open-label, single-centre 4-period sequential study of varying strategies of perioperative IV fluid composition will test the hypothesis that a perioperative protocol for the administration of chloride-poor intravenous fluids compared to chloride-rich intravenous fluids will reduce the incidence of AKI after adult cardiothoracic surgery.

Detailed Description
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After an initial run-in period of approximately 1 month (using a chloride-rich fluid strategy), the first study period of 5 months will commence, also comprising a chloride-rich perioperative IV fluid therapy strategy (0.9% saline or 4% albumin). This will include intraoperative fluid and postoperative fluid for the duration of stay in the intensive care unit. This will then be followed by a 1-month transition period before a second period of 5 months will commence where perioperative intravenous fluid therapy will consist of chloride-poor fluids (Lactated Ringer's solution or concentrated 20% albumin). A subsequent 1-month transition period will then be followed by a third period of 5 months characterized by perioperative IV fluid therapy with an alternative combination of chloride-poor solutions (PlasmaLyte® 148 or concentrated 20% albumin). A final 1-month transition period will be followed by a fourth and final period of 5 months characterized by a return to perioperative IV fluid therapy with chloride-rich fluids (0.9% saline or 4% albumin). A final 1-month run-off period using a chloride-rich perioperative fluid strategy will follow prior to study completion.

Official Title
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Does Varying the Chloride Content of Intravenous Fluid Alter the Risk of Acute Kidney Injury After Cardiac Surgery?

Conditions
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Patients Undergoing Cardiothoracic Surgery

Intervention / Treatment
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* Other: Low-chloride perioperative intravenous fluid strategy
* Other: High-chloride perioperative intravenous fluid strategy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All adult patients undergoing surgery by Division of cardiothoracic surgery Exclusion Criteria: Nil

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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Design Details

Primary Purpose: Prevention
Allocation: Non-Randomized
Intervention Model: Sequential Assignment
Interventional Model Description: Investigator-initiated, prospective, open-label, 4-period sequential study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Chloride-rich IV fluid<br>The chloride-rich strategy will include 0.9% saline as the perioperative crystalloid of choice with 4% albumin as the perioperative colloid of choice. | Other: High-chloride perioperative intravenous fluid strategy<br> <br> * Other names: Chloride-rich IV fluid;|
| Active Comparator: Chloride-poor IV fluid<br>A low-chloride strategy of perioperative IV fluid will include PlasmaLyte 148 or Hartmann's solution as the crystalloid of choice with 20% albumin as the colloid of choice. | Other: Low-chloride perioperative intravenous fluid strategy<br>* The low-chloride perioperative IV fluid strategy will include the use of PlasmaLyte 148 or Hartmann's solution as the crystalloid of choice and 20% albumin as the colloid of choice.<br>* Other names: Chloride-poor IV fluid;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak ∆ serum creatinine | Maximum change in serum creatinine from baseline | 5 days postoperatively | 
| AKI ≥stage2 | AKI, ≥stage2, defined by creatinine-based KDIGO criteria | 5 days postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Individual stages of AKI | Individual stages of AKI, defined by creatinine-based KDIGO criteria | 7 days | 
| Mortality | Mortality | On discharge from hospital (7-30 days) | 
| Renal replacement therapy | Renal replacement therapy | On discharge from hospital (7-30 days) | 
| ICU Length of stay | ICU Length of stay | On discharge from hospital (7-30 days) | 
| Hospital Length of stay | Hospital Length of stay | On discharge from hospital (7-30 days) | 
| Time to first extubation | Time to first extubation | On discharge from hospital (7-30 days) | 
| Red cell transfusion requirement | Volume of packed red blood cells transfused | Intraoperative and postoperatively through completion of postoperative day 1 or ICU discharge, whichever occurred first | 
| Fresh frozen plasma transfusion requirement | Volume of fresh frozen plasma transfused | Intraoperative and postoperatively through completion of postoperative day 1 or ICU discharge, whichever occurred first | 
| Platelet transfusion requirement | Volume of platelets transfused | Intraoperative and postoperatively through completion of postoperative day 1 or ICU discharge, whichever occurred first | 
| Cryoprecipitate transfusion requirement | Volume of cryoprecipitate transfused | Intraoperative and postoperatively through completion of postoperative day 1 or ICU discharge, whichever occurred first | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cardiac surgery, Thoracic surgery, acute kidney injury, hyperchloremia, intravenous fluid