Comparing Air Embolic Load in Two Venous Cannulation Methods, 40 Patients Undergoing Elective Valve Surgery.

Study Overview
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Brief Summary
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The goal of this single center prospective controlled observational and interventional trial is to investigate and compare origin of air emboli when different venous cannulation methods is used in patients undergoing cardiac surgery with extracorporeal circulation. 40 consecutive elective patients will be included in two groups, depending on the procedure requiring bicaval or cavoatrial cannulation. After assorted into respective group, patients will be block randomized (five groups consisting of eight patients each) to either intervention group (low venous reservoir volume, 200-300 mL) or control group (venous reservoir volume > 300 mL). Primary endpoint is to investigate if the amount of air emboli passing through the oxygenator to the arterial line differs between bicaval and cavoatrial venous cannulation during extracorporeal circulation. Secondary endpoints are the relative difference in amount air emboli between the groups, if there is any correlation between the amount of air in venous line and the amount of air passing through the oxygenator to the arterial line during extracorporeal circulation, and if difference is seen on the amount of air passing through the oxygenator depending on the level of volume in the venous reservoir.

Official Title
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Does Venous Cannulation Method Affect Air Embolic Load to the Patient During Extracorporeal Circulation?

Conditions
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Extracorporeal Circulation; Complications, Air Embolism

Intervention / Treatment
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* Diagnostic Test: Volume control


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients > 18 years Elective bicaval cannulation (mitral valve repair/replacement (MVR) or MVR + coronary artery bypass grafting (CABG)) Elective cavoatrial cannulation (aortic valve repair/replacement (AVR) or AVR + CABG Planned normothermia (35-37˚C) Exclusion Criteria: Acute heart surgery Adult Congenital Heart Disease (ACHD) surgery Endocarditis Reoperation (primary procedure > 2 years ago) Perioperative iatrogenic adverse events (major bleeding, aortic dissection, other severe complications)

Ages Eligible for Study
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Minimum Age: 18 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

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control group<br>Patient will during extracorporeal circulation be monitored and held in the range of > 300 mL in the venous reservoir. Patient will recieve fluid if needed to maintain correct level (crystalloids, colloids or erytrocytes depending on patients clinical status). | |
| Experimental: Interventional group<br>Patient will during extracorporeal circulation be monitored and held in the range of 200 - 300 mL in the venous reservoir. To maintain correct level of volume, any excessive fluid will be drained into a sterile infusion bag during extracorporeal circulation. After the surgery, the patient will recieve the volume to ensure correct volume status. | Diagnostic Test: Volume control<br>* Volume control in venous reservoir during extracorporeal circulation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in count (number) of air emboli passing through the oxygenator to the arterial line between bicaval and cavoatrial venous cannulation. | Bubble counter measurements | 1 day (During extracorporeal circulation) | 
| Difference in volume (nano liter) of air emboli passing through the oxygenator to the arterial line between bicaval and cavoatrial venous cannulation. | Bubble counter measurements | 1 day (During extracorporeal circulation) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in the amount of air emboli in venous tubing between bicaval and cavoatrial cannulation. | Bubble counter measurements | 1 day (During extracorporeal circulation) | 
| Correlation between the amount of air in venous line and the amount of air passing through the oxygenator to the arterial line during extracorporeal circulation. | Bubble counter measurements | 1 day (During extracorporeal circulation) | 
| Difference in amount of air passing through the oxygenator depending on the volume in the venous reservoir (200-300 mL versus > 300 mL). | Bubble counter measurements | 1 day (During extracorporeal circulation) |