Limiting IV Chloride to Reduce AKI After Cardiac Surgery (LICRA)

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

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.

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.

The chloride-rich strategy will include 0.9% saline as the perioperative crystalloid of choice with 4% albumin as the perioperative colloid of choice.

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.

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.

Intraoperative and postoperatively through completion of postoperative day 1 or ICU discharge, whichever occurred first

Intraoperative and postoperatively through completion of postoperative day 1 or ICU discharge, whichever occurred first

Intraoperative and postoperatively through completion of postoperative day 1 or ICU discharge, whichever occurred first

Intraoperative and postoperatively through completion of postoperative day 1 or ICU discharge, whichever occurred first

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

McIlroy DR, Murphy D, Shotwell MS, Bhatia D. Peak Serum Chloride and Hyperchloremia in Patients Undergoing Cardiac Surgery Is Not Explained by Chloride-Rich Intravenous Fluid Alone: A Post-Hoc Analysis of the LICRA Trial. J Cardiothorac Vasc Anesth. 2021 May;35(5):1321-1331. doi: 10.1053/j.jvca.2020.07.085. Epub 2020 Aug 7.

McIlroy D, Murphy D, Kasza J, Bhatia D, Wutzlhofer L, Marasco S. Effects of restricting perioperative use of intravenous chloride on kidney injury in patients undergoing cardiac surgery: the LICRA pragmatic controlled clinical trial. Intensive Care Med. 2017 Jun;43(6):795-806. doi: 10.1007/s00134-017-4772-6. Epub 2017 Mar 25.