Calcium Administration in Cardiac Surgery (ICARUS)

August 2, 2026 updated by: Meshalkin Research Institute of Pathology of Circulation

Calcium Administration in Patients Undergoing Cardiac Surgery Under Cardiopulmonary Bypass (ICARUS Trial): Prospective Randomized, Double-blind Placebo-controlled Superiority Trial

Termination of cardiopulmonary bypass is a critical step in any cardiac surgical procedure and requires a thorough planning. Debate about rationale of calcium administration during weaning of cardiopulmonary bypass has been conducted for several decades; however, a consensus has not been yet reached.

Perioperative hypocalcemia can develop because of haemodilution or calcium binding from heparin, albumin and citrate. Perioperative hypocalcemia is often complicated by development of arrhythmias, especially QT interval prolongation. Furthermore, low content of calcium can lead to vascular tone disorders, violation of neuromuscular transmission, altered hemostasis and heart failure, resistant to inotropic agents, especially in patients with concomitant cardiomyopathy.

On the other hand, hypercalcaemia is a dangerous complication in cardiac surgery. Among the fatal, but rather rare complications, there are acute pancreatitis and the phenomenon of the "stone heart", which is essentially a reperfusion injury of the myocardium caused by rapid calcium overload. Hypercalcaemia can also trigger rhythm disturbances, hypertension, increase systemic vascular resistance, reduce diastolic compliance and impair relaxation of the myocardium due to excessive calcium intake into the cardiomyocytes, cause coronary vasospasm and aggravate ischaemic myocardial damage, impair arterial graft blood flow during aortocoronary and mammary coronary bypass surgery.

To date, there is a lack of data indicating clinical efficacy of calcium administration before separation from CPB. Therefore, we designed this randomized controlled trial to test the hypothesis whether calcium administration at termination of CPB will reduce the need for inotropic support at the end of surgery.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

820

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Bahrain
      • Manama, Bahrain
        • Sh. Mohammed Bin Khalifa Bin Salman Al-Khalifa Cardiac Center
  • Russia
      • Astrakhan, Russia
        • Federal Center for Cardiovascular Surgery
      • Chelyabinsk, Russia
        • Federal Center for Cardiovascular Surgery
      • Khanty-Mansiysk, Russia
        • District clinical hospital
      • Moscow, Russia
        • B.V. Petrovsky Russian Scientific Surgery Center
      • Moscow, Russia
        • M. Vladimirsky Moscow Regional Research Cinical Institute (MONIKI)
      • Novosibirsk, Russia, 630055
        • Meshalkin Research Institute of Pathology of Circulation
      • Penza, Russia
        • Federal Center for Cardiovascular Surgery
      • Saint Petersburg, Russia
        • St Petersburg University Multifunctional Clinical Centre
      • Tomsk, Russia
        • Tomsk National Research Medical Center
  • Saudi Arabia
      • Mecca, Saudi Arabia
        • King Abdullah Medical City

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

14 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • surgery under cardiopulmonary bypass
  • valve or valve surgery + CABG
  • age > 18 years
  • signed informed consent

Exclusion Criteria:

  • emergency surgery
  • isolated aortic valve repair/replacement
  • isolated CABG
  • planned (before surgery) blood transfusion
  • redo surgery
  • known allergy to the study drug
  • pregnancy
  • current enrollment into another RCT (in the last 30 days)
  • previous enrollment and randomization to ICARUS trial - liver cirrhosis (Child B or C)
  • transfusion during CPB
  • hypo- or hyperparathyreosis

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Calcium chloride
Participants randomly assigned to the experimental group will receive 15 mg/kg of calcium chloride (bolus) intravenously during separation from cardiopulmonary bypass
Drug: Calcium Chloride
Calcium Chloride
Placebo Comparator: 0,9% Sodium Chloride
Participants randomly assigned to the placebo group will receive equivalent amount of placebo intravenously during separation from cardiopulmonary bypass
Drug: 0.9% Sodium Chloride
0.9% Sodium Chloride

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Inotropic support
Time Frame: Intraoperatively
Number of patients requiring inotropic and/or vasopressor support started at any dose during the period starting at termination of CPB and ending at completion of surgery
Intraoperatively

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Duration of inotropic support after surgery
Time Frame: 30 days after surgery
Duration of infusion of any vasoinotropic agent at any dose
30 days after surgery
Plasma Ca2+ concentration before and after drug administration
Time Frame: Intraoperatively
Intraoperatively
Time spent in theatre after cardiopulmonary bypass
Time Frame: Intraoperatively
Intraoperatively
Duration of ventilation
Time Frame: Up to 30 day after randomization
Up to 30 day after randomization
Duration of intensive care unit stay
Time Frame: Up to 30 day after randomization
Up to 30 day after randomization
Myocardial infarction
Time Frame: Up to 30 day after randomization
Number of patients who develop myocardial infarction
Up to 30 day after randomization
Type 1 and type 2 neurological complications
Time Frame: Up to 30 day after randomization
Number of patients who develop type 1 and type 2 develop myocardial infarction
Up to 30 day after randomization
Postoperative blood loss
Time Frame: Postoperative day 1
Postoperative blood (ml/kg) loss will be measured on the morning of postoperative day 1
Postoperative day 1
Need for blood transfusion after surgery
Time Frame: Up to 30 day after randomization
Number of patients who will need transfuion of any blood products (red cells, fresh frozen plasma, cryoprecipitate)
Up to 30 day after randomization
Myocardial ischaemia on ECG after arrival to ICU
Time Frame: Postoperative day 1
Number of patients who develop myocardial ischemia
Postoperative day 1
Concentration of alpha-amylase after surgery
Time Frame: Postoperative day 1
Postoperative day 1
Internal mammary artery vascular resistance (if available)
Time Frame: Intraoperatively
Will be defined by intraoperative graft flow measurements
Intraoperatively
Vasoactive-inotropic score
Time Frame: Postoperative day 1
Vasoactive-inotropic score will be measured 4 hours after transfer to ICU and on morning of postoperative day 1. The inotropic score will be calculated using the following formula: Dobutamine dose (in mcg/kg/min) + Dopamine dose (in mcg/kg/min) + Enoximone dose (in mcg/kg/min) + [Epinephrine dose (in mcg/kg/min) x 100] + [Norepinephrine dose (in mcg/kg/min) x 100].
Postoperative day 1
CPB duration
Time Frame: intraoperatively
Duration of cardiopulmonary bypass
intraoperatively
ICU readmission
Time Frame: Postoperatively until hospital discharge
Readmission to intensive care unit
Postoperatively until hospital discharge
Hospital stay
Time Frame: Postoperatively until hospital discharge
Duration of hospital stay
Postoperatively until hospital discharge

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Meshalkin Research Institute of Pathology of Circulation

Collaborators

Università Vita-Salute San Raffaele

Investigators

  • Principal Investigator: Vladimir Lomivorotov, Meshalkin Research Institute of Pathology of Circulation

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 14, 2019

Primary Completion (Actual)

July 13, 2025

Study Completion (Actual)

August 8, 2025

Study Registration Dates

First Submitted

December 7, 2018

First Submitted That Met QC Criteria

December 9, 2018

First Posted (Actual)

December 12, 2018

Study Record Updates

Last Update Posted (Actual)

August 4, 2026

Last Update Submitted That Met QC Criteria

August 2, 2026

Last Verified

November 1, 2024

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 21/2019

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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