The Precision of Pulmonary Artery Cardiac Output-measurements in Spontaneously Breathing Patients

Study Overview
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Brief Summary
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The intention of this study is to determine whether the precision of the measure of cardiac output can be optimized by conducting the measurement while the participant is instructed to exhale slowly. This will be compared to measurements done at random to respiration and timed with the participant's spontaneous expiration.

Official Title
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Comparison of the Precision of Cardiac Output-measures at Random to Respiration, Synchronised With Expiration and Instructed Slow Exhalation, Obtained by Pulmonal Artery Catheter Thermodilution Technique With Cold Injection

Conditions
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Heart Diseases

Intervention / Treatment
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* Procedure: Cardiac output measurement at random to respiration
* Procedure: Cardiac output measurement synchronised at start of expiration
* Procedure: Cardiac output measurement timed to instructed exhalation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Every patient that receives a pulmonary artery catheter (PAC) related to elective cardiac surgeries, informed and written consent to participation in the study in accordance with the Helsinki declaration hemodynamic stability Exclusion Criteria: Hemodynamical instability atrial fibrillation tricuspid insufficiency ≥ grade 2 hemodialysis or other conditions where extra volume load can be negative, lack of ability to give a written consent to participate in the study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: random to respiration<br>Cardiac output measurement at random to respiration | Procedure: Cardiac output measurement at random to respiration<br>* Cardiac output measurement obtained by pulmonary artery catheter thermodilution technique (PAC TD)<br>|
| Experimental: timed with expiration start<br>Cardiac output measurement synchronised at start of expiration. | Procedure: Cardiac output measurement synchronised at start of expiration<br>* Cardiac output measurement obtained by PAC TD<br>|
| Experimental: timed to instructed exhalation<br>Cardiac output measurement timed to instructed exhalation. The patient will receive instructions to exhale slowly using a peak expiratory flow (PEF)-flute and the cardiac output measurement will be started (i.e bolus given) at the start of expiration. | Procedure: Cardiac output measurement timed to instructed exhalation<br>* Cardiac output measurement obtained by PAC TD<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The observed variance amongst the cardiac output measures | The measures will be obtained the first postoperative morning by pulmonary artery catheter thermodilution technique. In total 24 measurements will be done in each patient, i.e 8 measurements in each interventional series described later. The variance observed will create the foundation for calculating the precision of the measures. | 1 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cardiac surgical procedures, Pulmonary Artery Catheterizations, Cardiac output, Swan Ganz Catheterization