Heart and Lung Procurement and Transplantation

Algorithmic Step-by-Step Technique for Combined Heart and Lung Procurement

Technique of Dr. Sam Zeraatiannejaddavani, MD

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I. Fundamental Principles

Combined heart and lung procurement is a physiology-driven, time-sensitive operation in which preservation of microvascular integrity is paramount. The operative strategy prioritizes hemodynamic stability, controlled ischemia, lung-protective ventilation, and precise sequencing of vascular control. All steps are performed in constant coordination with anesthesia and abdominal procurement teams.

The primary objectives are to achieve complete myocardial arrest, uniform pulmonary flush, avoidance of warm ischemia, prevention of pulmonary edema, and safe explantation with intact vascular and airway structures.

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II. Donor Readiness Algorithm

Prior to incision, donor suitability is confirmed through a structured decision process:

If mean arterial pressure is maintained at or above 60 mmHg with minimal vasoactive support, oxygenation demonstrates a PaO₂ greater than 300 mmHg on 100% FiO₂ with low PEEP, echocardiography confirms preserved biventricular function, bronchoscopy reveals no aspiration or purulence, and metabolic parameters are corrected, then procurement proceeds.

If any of these conditions are not met, optimization is attempted before incision or the organ is declined.

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III. Operative Setup and Ventilatory Strategy

The donor is positioned supine with arms tucked and slight cervical extension to facilitate later tracheal control. Continuous invasive monitoring is established. Mechanical ventilation is adjusted to lung-protective settings with moderate tidal volumes and minimal PEEP. High oxygen concentrations are avoided until immediately before organ flushing to limit oxidative injury.

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IV. Surgical Procedure

Step 1: Median Sternotomy and Initial Exposure

A standard median sternotomy is performed. The pericardium is opened vertically and suspended. The heart is inspected for contractility, chamber size, and gross pathology. The pulmonary artery and pleural reflections are visually assessed. Lung manipulation is minimized at this stage to prevent capillary leak and edema.

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Step 2: Airway Evaluation and Lung Recruitment

Flexible bronchoscopy is performed to clear secretions and evaluate the tracheobronchial tree. Any retained secretions are gently aspirated. Recruitment maneuvers are applied cautiously if atelectasis is present. The lungs are reassessed visually for symmetry, compliance, and color.

If significant aspiration, purulence, or structural abnormality is identified, lung suitability is reassessed before proceeding.

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Step 3: Cannulation and Perfusion Planning Algorithm

The perfusion strategy is determined based on the intended organs for recovery. For combined heart and lung procurement, both systemic and pulmonary flushes are required.

The ascending aorta is prepared for cardioplegia delivery. The main pulmonary artery is dissected and prepared for lung preservation flush. A left atrial vent is placed via the left atrial appendage to ensure adequate decompression during cardioplegia administration.

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Step 4: Systemic Anticoagulation

Systemic heparin is administered intravenously at a full donor dose. A short interval is observed to allow complete circulation, and adequate anticoagulation is confirmed before vascular clamping.

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Step 5: Aortic Cross-Clamp and Myocardial Protection

Once hemodynamic stability is confirmed, the ascending aorta is cross-clamped. Cold cardioplegia is immediately administered, resulting in rapid and complete diastolic cardiac arrest. The left atrium is vented continuously to prevent distension and subendocardial injury.

Myocardial protection must be complete before proceeding with pulmonary flush to avoid competitive flow and incomplete arrest.

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Step 6: Pulmonary Artery Flush and Lung Preservation

After cardiac arrest is achieved, the pulmonary artery flush is initiated using cold lung preservation solution at strictly controlled low pressure. The lungs are ventilated gently during the flush to facilitate homogeneous distribution of solution and prevent vascular collapse. Pulmonary veins are never clamped during this phase to avoid parenchymal congestion.

FiO₂ is reduced during the flush to minimize oxygen-derived free radical injury.

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Step 7: Topical Cooling and Pleural Dissection

Ice slush is placed in the mediastinum for topical cooling. Both pleural spaces are entered carefully. Inferior pulmonary ligaments are divided to fully mobilize the lungs. Care is taken to avoid direct compression or torsion of the pulmonary parenchyma.

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Step 8: Cardiac Explantation

The superior vena cava is transected first, followed by the inferior vena cava. The ascending aorta and main pulmonary artery are divided with adequate length preserved. The heart is removed from the chest and immediately placed into cold preservation solution, ensuring minimal warm ischemic exposure.

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Step 9: Lung Procurement

Depending on transplant requirements, lungs may be procured en bloc or as separate bilateral organs. A generous left atrial cuff is created circumferentially, incorporating all pulmonary veins. The trachea is divided at the level of the carina while the lungs are partially inflated to protect the airway and prevent atelectasis.

The lungs are removed en bloc and immediately packaged in cold preservation solution using sterile triple-bag technique.

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V. Ischemic Time Strategy

Cold ischemic time is actively managed throughout the procedure. Heart ischemic time is kept under four hours whenever possible. Lung ischemic time is maintained within six to eight hours. Transport logistics are confirmed before explantation to prevent unnecessary delay.

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VI. Intraoperative Pitfalls and Preventive Strategies

Pulmonary edema is prevented by strict control of pulmonary artery flush pressure and minimal lung manipulation. Airway injury is avoided by ensuring lung inflation before tracheal division. Incomplete myocardial arrest is prevented through adequate cardioplegia dosing and venting. Hemodynamic collapse is avoided by delaying cross-clamp until full physiologic optimization is achieved.

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VII. Final Procurement Checklist

Before leaving the operating room, all vascular cuffs are inspected for adequacy, the airway is examined for integrity, organs are correctly labeled, preservation temperature is confirmed between zero and four degrees Celsius, and transport timing is reconfirmed with the recipient teams.

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VIII. Author’s Technical Philosophy

Dr. Sam Zeraatiannejaddavani

This technique emphasizes physiology over speed, lung microvascular preservation over aggressive flushing, and disciplined sequencing over improvisation. Successful heart and lung procurement is not a technical exercise alone, but a coordinated physiologic operation that begins before incision and ends only when the organs are safely implanted.

Dr.Sam Zeraatian Nejad Davani, Attending Professor of Cardiovascular Surgery and Head of Department of Transplant and OPO of IUMS and Superfellowship of Advanced Thoracic Organs Transplant of NM in CTI USA Chicago.