Heart Procurement and Putting the Heart on OCS Machine with Perfusionist
Heart Procurement and Placement on OCS – Stepwise Approach
I. Preoperative Preparation
1.Team Preparation
•Confirm donor consent and organ allocation.
•Communicate with recipient surgical team and perfusion/OCS team.
•Confirm availability of all equipment: OCS device, cannulas, prime solutions, perfusate.
2.Donor Assessment
•Review hemodynamic stability, echocardiography, coronary angiography if available.
•Confirm blood type match and donor serologies.
•Ensure electrolytes, temperature, and acid-base balance are optimized.
3.OCS Setup
•Assemble OCS system, check priming solution, and ensure temperature sensors, pressure sensors, and pump settings are functional.
•Prime the OCS with perfusate (usually donor blood-based solution) and ensure oxygenation.
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II. Donor Sternotomy and Exposure
1.Median Sternotomy
•Incise skin and subcutaneous tissue, open sternum with sternal saw.
•Retract sternum with sternal retractor to expose mediastinum.
2.Pericardial Opening
•Open pericardium longitudinally.
•Place traction sutures for exposure of ascending aorta and pulmonary artery.
•Inspect the heart and great vessels.
3.Assessment
•Confirm heart quality and size.
•Evaluate for any trauma or anatomical anomalies.
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III. Cannulation for Cardioplegia
1.IV Cannulation
•Place cannulas in superior and inferior vena cava for venous drainage if needed.
•Consider venting left ventricle via pulmonary vein or left atrium.
2.Aortic Cannulation
•Place aortic cross-clamp preparation.
•Insert cardioplegia catheter into aortic root.
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IV. Cardioplegia and Cardiac Arrest
1.Systemic Heparinization
•Administer heparin (300–400 IU/kg) to donor.
2.Cross-Clamp Aorta
•Apply aortic cross-clamp to stop systemic flow.
3.Deliver Cardioplegia
•Cold crystalloid or blood cardioplegia into aortic root.
•Ensure complete cardiac arrest and myocardial protection.
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V. Heart Explantation
1.Division of Great Vessels
•Transect SVC and IVC near atria.
•Transect ascending aorta above sinotubular junction.
•Transect pulmonary artery at main PA bifurcation.
•Excise pulmonary veins with atrial cuff if needed.
2.Cardiac Removal
•Carefully lift heart from pericardial cavity.
•Avoid traction on coronaries.
•Place heart into sterile organ basin or directly onto OCS preparation field.
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VI. Heart Preparation for OCS
1.Cannulation for OCS
•Insert aortic cannula into donor aorta for arterial inflow.
•Insert pulmonary artery cannula for venous return into OCS circuit.
•Place venting cannula into left atrium if indicated.
2.Priming and Flushing
•Connect to OCS and prime circuit with donor blood-based perfusate.
•Slowly perfuse heart to remove air, debris, and cold cardioplegia solution.
•Confirm no leaks and proper cannula positions.
3.Temperature and Pressure Monitoring
•Start warm perfusion (~34°C) with oxygenated blood.
•Monitor aortic pressure (50–70 mmHg), coronary flow, heart rate, and lactate production.
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VII. Initiating OCS Perfusion
1.Activate OCS Device
•Start pulsatile perfusion.
•Adjust flow and oxygen delivery according to device parameters.
2.Functional Assessment
•Observe heart beating on OCS, evaluate contractility, coronary flow, and hemodynamics.
•Record lactate levels every 30 minutes to assess viability.
3.Transport Readiness
•Ensure OCS battery charged, alarm systems functional, and heart is stable.
•Seal circuit and prepare for transport to recipient OR.
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VIII. Key Tips and Pitfalls
•Avoid excessive handling of coronary arteries.
•Ensure air-free connections when connecting to OCS.
•Maintain continuous perfusion, do not allow heart to become ischemic.
•Continuous monitoring of lactate and perfusion pressures is critical for successful preservation.
Dr.Sam Zeraatian Nejad Davani, Cardiovascular and Transplant surgeon. Advanced Fellow of Thoracic Organs Transplantation Chicago Illinois.