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Trial registered on ANZCTR

Registration number
Ethics application status
Not yet submitted
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Cardiac Output Measurement using carbon dioxide inhalation in Open Heart Surgery Patients.
Scientific title
Cardiac Output Measurement using a Servo-Controlled CO2 Addition Fick Approach in Open Heart Surgery Patients with a Pulmonary Artery Catheter Placed.
Secondary ID [1] 281297 0
Universal Trial Number (UTN)
Trial acronym
CO2 FICK cardiac output
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Chronic heart failure 287517 0
Condition category
Condition code
Cardiovascular 287835 287835 0 0
Other cardiovascular diseases
Respiratory 287836 287836 0 0
Other respiratory disorders / diseases
Anaesthesiology 287871 287871 0 0
Other anaesthesiology

Study type
Description of intervention(s) / exposure
In Fick CO2 cardiac output (CO) we need to measure CO2 production, and arterial and venous CO2 content of blood.
CO2 production is measured in expired gases. Arterial CO2 content is measured using arterial blood gas from arterial line. Venous CO2 content is measured by adding CO2 to the inspired gas (mass flow-controller) at the CO2 production rate, causing arterial and end expired CO2 to rise to the mixed venous level.This measurement takes approximately 1 minute, measurements may take place every 15-30 minutes for 4 hours.
Intervention code [1] 285770 0
Treatment: Devices
Comparator / control treatment
This is not a randomised controlled trial. We seek to compare CO measured using a CO2 Fick approach with CO measured using a pulmonary artery catheter. The innovation is the manner in which the CO2 Fick is performed.
A pulmonary artery catheter is the gold standard CO measurement. All patients undergo both methods of measurement simultaneously and thus act as their own control.
Control group

Primary outcome [1] 288061 0
Accuracy of CO2 cardiac output method compared with the gold standard of the pulmonary artery catheter.
Timepoint [1] 288061 0
Whilst the patient is endotracheally intubated and has a pulmonary artery catheter insitu.
Secondary outcome [1] 299354 0
Calculation using mathematical models suggests that the mixed venous pCO2 measured using the CO2 addition method equals the mixed venous pCO2 measured using pulmonary artery blood. This is presently untested.
Timepoint [1] 299354 0
Whilst the patient is endotracheally intubated and has a pulmonary artery catheter insitu.

Key inclusion criteria
All consented patients undergoing elective open heart surgery and who have a pulmonary artery catheter placed.
Minimum age
18 Years
Maximum age
90 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Pregnant women.
Patients with a raised pulmonary artery pressure.
Patients with Obstructive airways disease and raised pCO2.
Patients with a raised intracranial pressure or primary cerebral disease.

Study design
Purpose of the study
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Single group
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 286062 0
Government body
Name [1] 286062 0
Department of Business and Innovation, Government of Vic
Address [1] 286062 0
Spring Street, Melbourne , Victoria 3000
Country [1] 286062 0
Primary sponsor type
Southern Health
Monash Medical Centre
246 Clayton Road, Clayton Victoria 3168
Secondary sponsor category [1] 284880 0
Name [1] 284880 0
Address [1] 284880 0
Country [1] 284880 0

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 288114 0
Southern Health Research and Ethics Committee
Ethics committee address [1] 288114 0
246 Clayton Road, Clayton Victoria 3168
Ethics committee country [1] 288114 0
Date submitted for ethics approval [1] 288114 0
Approval date [1] 288114 0
Ethics approval number [1] 288114 0

Brief summary
This is a study to find a new way to measure the cardiac output (CO), the amount of blood that leaves the heart every minute. Presently in order to measure CO we have to insert an expensive catheter into the heart which can bring complications.
The present study aims to measure CO by inhaling small puffs of carbon dioxide which is normally excreted by the lung. By measuring the amount by which the blood concentration of CO2 rises we can know the blood flow through the lung.This is equal to the CO.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 34755 0
Address 34755 0
Country 34755 0
Phone 34755 0
Fax 34755 0
Email 34755 0
Contact person for public queries
Name 18002 0
A/Prof Geoffrey Parkin
Address 18002 0
246 Clayton Road, Clayton Victoria,3168
Country 18002 0
Phone 18002 0
+61 3 9594 3277/3616
Fax 18002 0
+61 3 9594 6297
Email 18002 0
Contact person for scientific queries
Name 8930 0
A/Prof Geoffrey Parkin
Address 8930 0
246 Clayton Road, Clayton Victoria, 3168
Country 8930 0
Phone 8930 0
+61 3 9594 3277/3616
Fax 8930 0
+61 3 9594 6297
Email 8930 0

No information has been provided regarding IPD availability
Summary results
No Results