Trial Review

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
Help: Registration number
ACTRN12626001127392p
Ethics application status
Help: Ethics application status
Submitted, not yet approved
Date submitted
Help: Date submitted
16/08/2026
Date registered
Help: Date registered
10/09/2026
Date last updated
Help: Date last updated
10/09/2026
Date data sharing statement initially provided
Help: Data sharing statement date
10/09/2026
Type of registration
Help: Type of registration
Prospectively registered

Titles & IDs
Public title
Calcium for Lowering Vasopressor use in cardiac surgery: a phase II feasibility trial
Scientific title
Calcium for Lowering Vasopressor use in cardiac surgery requiring cardiopulmonary bypass: a phase II feasibility trial
Additional trial identifiers [1] 315937 0
None
Universal Trial Number (UTN)
Trial acronym
CALVARY-II
Related trial records

Health condition
Health condition(s) studied:
Cardiac surgery 339728 0
Condition category
Condition code
Anaesthesiology 335982 335982 0 0
Anaesthetics
Cardiovascular 335983 335983 0 0
Other cardiovascular diseases

Intervention/exposure
Study type
Interventional
Description of the intervention or exposure
- Name: Calcium chloride infusion
- Dose: 10% in normal saline, 60mls, refillable if required
> Maximum possible dose: 72mls of 10% calcium chloride (48.96 mmol of elemental calcium)
> Refills will be provided once the current 60mls syringe has been completely depleted.

- Duration of treatment: 24 hours from initiation of cardiopulmonary bypass
- Mode of delivery: Intravenous infusion
- Adherence: Administered by trial staff and ICU nursing/medical teams. Infusion rates will be titrated based on serum calcium levels, which are monitored at least every 4 hours.
Intervention code [1] 332548 0
Treatment: Drugs
Description of the comparator or control
- Name: 0.9% normal saline infusion
- Dose: 60mls syringe, refillable.
- Duration of treatment: 24 hours from initiation of cardiopulmonary bypass
- Mode of delivery: Intravenous infusion
- Adherence: Administered by trial staff and ICU nursing/medical teams. Infusion rates will be titrated based on serum calcium levels, which are monitored at least every 4 hours.
Control group
Placebo

Outcomes
Primary outcome [1] 346647 0
Recruitment rates
Timepoint [1] 346647 0
Over course of study recruitment period
Secondary outcome [1] 454661 0
Vasopressor inotropic score
Timepoint [1] 454661 0
At 24 hours, Highest in ICU up to 7 day, time-weighted VIS the first 24 hours of ICU admission
Secondary outcome [2] 454662 0
Haemodynamic efficacy (area under the time-curve MAP<65)
Timepoint [2] 454662 0
Hourly for the first 24 hours from ICU admission,
Secondary outcome [3] 454665 0
Mortality
Timepoint [3] 454665 0
At ICU discharge, hospital discharge, 30 days post-operative
Secondary outcome [4] 466868 0
Adherence to treatment strategy and intervention delivery (primary outcome), assessed as a composite outcome
Timepoint [4] 466868 0
From initiation of treatment, until end of treatment (24 hours in total)
Secondary outcome [5] 466869 0
Data completeness (primary outcome)
Timepoint [5] 466869 0
End of study
Secondary outcome [6] 466870 0
Vasopressor free days
Timepoint [6] 466870 0
Up to 7 days from ICU admission
Secondary outcome [7] 466871 0
Cumulative vasopressor dose
Timepoint [7] 466871 0
Up to ICU discharge
Secondary outcome [8] 466872 0
Bradycardia (HR<60)
Timepoint [8] 466872 0
During infusion of study drug
Secondary outcome [9] 466873 0
Parasthesia
Timepoint [9] 466873 0
During infusion of study drug
Secondary outcome [10] 466874 0
Syncope
Timepoint [10] 466874 0
During infusion of study drug
Secondary outcome [11] 466875 0
Hypercalcaemia (iCa >1.35 mmol/L)
Timepoint [11] 466875 0
During infusion of study drug
Secondary outcome [12] 466876 0
Myocardial infarction (4UDMI)
Timepoint [12] 466876 0
Index hospitalisation
Secondary outcome [13] 466880 0
Prosthetic valve thrombosis
Timepoint [13] 466880 0
Index hospitalisation
Secondary outcome [14] 466881 0
Blood loss
Timepoint [14] 466881 0
Intra-operative, and 24 hours post-operative
Secondary outcome [15] 466882 0
Acute kidney injury (KDIGO)
Timepoint [15] 466882 0
7 days post operative
Secondary outcome [16] 466883 0
Packed red-cell transfusion requirements
Timepoint [16] 466883 0
7 days post operative
Secondary outcome [17] 466884 0
Length of stay
Timepoint [17] 466884 0
From ICU admission to discharge, hospital admission to discharge
Secondary outcome [18] 466885 0
Time to extubation
Timepoint [18] 466885 0
From time of intubation to extubation
Secondary outcome [19] 467662 0
Coronary graft thrombosis
Timepoint [19] 467662 0
Index Hospitalisation

Eligibility
Key inclusion criteria
1. Age >=18 years
2. Elective cardiac surgery requiring cardiopulmonary bypass, including:
- Coronary artery bypass grafting (CABG)
- Valvular heart surgery
- Combined CABG with valvular heart surgery
- Aortic root surgery
3. Able to provide consent
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Healthy volunteers
No
Key exclusion criteria
1. Emergency or redo surgery
2. Severe left ventricular dysfunction (ejection fraction 2.6 mmol/l or serum ionised calcium > 1.35 mmol/l)
3. End-stage kidney disease
4. Known hypercalcaemia (defined as serum calcium >2.6 mmol/l or serum ionised calcium > 1.35 mmol/l)
5. Known hyperparathyroidism (elevated intact parathyroid hormone in the presence of normal or raised serum calcium levels)
6. Participation in other interventional studies affecting calcium haemostasis
7. Allergy or known contraindication to study drug
8. Prior participation in CALVARY-II
9. Pregnancy

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Sealed envelope
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer-generated randomisation schedule based upon random permuted blocks of varying sizes, prepared by an independent biostatistician using standard statistical software.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Phase 2
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
- Randomisation algorithm will be assessed using baseline characteristics.
- Blinding integrity will be assessed using a Clinician's guess of treatment assignment
- Data completeness will be assessed based on missingness of data from case report forms at the point of analysis.

Sample size calculation: We empirically selected 100 participants as our sample size, as this is a feasibility Phase II trial. To account for a 10% attrition rate, we aim to include 112 participants.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
30/01/2027
Actual
Date of last participant enrolment
Anticipated
31/12/2027
Actual
Date of last data collection
Anticipated
31/01/2028
Actual
Sample size
Target
112
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 320547 0
Hospital
Name [1] 320547 0
Epworth HealthCare
Country [1] 320547 0
Australia
Primary sponsor type
Hospital
Name
Epworth HealthCare
Address
Country
Australia
Secondary sponsor category [1] 323159 0
None
Name [1] 323159 0
Address [1] 323159 0
Country [1] 323159 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 319086 0
Alfred Hospital Ethics Committee
Ethics committee address [1] 319086 0
Ethics committee country [1] 319086 0
Australia
Date submitted for ethics approval [1] 319086 0
08/09/2026
Approval date [1] 319086 0
Ethics approval number [1] 319086 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 146210 0
A/Prof Ashwin Subramaniam
Address 146210 0
Epworth HealthCare Richmond, 89 Bridge Rd, Richmond VIC 3121, Australia
Country 146210 0
Australia
Phone 146210 0
+61 413 900 715
Fax 146210 0
Email 146210 0
[email protected]
Contact person for public queries
Name 146211 0
Ashwin Subramaniam
Address 146211 0
Epworth HealthCare Richmond, 89 Bridge Rd, Richmond VIC 3121, Australia
Country 146211 0
Australia
Phone 146211 0
+61 413 900 715
Fax 146211 0
Email 146211 0
[email protected]
Contact person for scientific queries
Name 146212 0
Ashwin Subramaniam
Address 146212 0
Epworth HealthCare Richmond, 89 Bridge Rd, Richmond VIC 3121, Australia
Country 146212 0
Australia
Phone 146212 0
+61 413 900 715
Fax 146212 0
Email 146212 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.