DCD Heart and Lung Explantation With TransMedics OCS Heart Recovery and EVLP Lung Perfusion
I. PRE-PROCUREMENT PREPARATION (DCD CONTEXT)
1. Donor Selection and Planning
•Confirm controlled DCD donor (Maastricht Category III).
•Review:
•Warm ischemic time (WIT) thresholds
•Functional warm ischemia (fWIT)
•Hemodynamics prior to WLST
•Bronchoscopy and chest imaging
•Cardiac echo and coronary risk profile
•Confirm:
•TransMedics OCS Heart primed and functional
•EVLP circuit (XVIVO / OrganOx / Toronto protocol) ready at recipient center or regional hub
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2. Team Roles
•Cardiac lead
•Thoracic (lung) lead
•Perfusionist (OCS)
•Anesthesia liaison
•Surgical coordinator (timekeeper for ischemia metrics)
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II. WITHDRAWAL OF LIFE-SUSTAINING THERAPY (WLST)
1.WLST occurs in ICU or OR per institutional policy.
2.Observe:
•Time to circulatory arrest
•Nadir systolic pressure <50 mmHg
•Oxygen saturation decline
3.Declare death after mandatory no-touch period (usually 2–5 minutes).
4.Record functional warm ischemia time (fWIT).
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III. RAPID ACCESS AND CARDIOPULMONARY REANIMATION
1. Transfer to Operating Room
•Immediate transport after declaration.
•Skin prep already completed when feasible.
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HEART PROCUREMENT FOR TRANSMEDICS OCS
1. Rapid Sternotomy
•Median sternotomy performed immediately.
•Open pericardium longitudinally.
•Identify:
•Ascending aorta
•Main pulmonary artery
•Superior and inferior vena cava
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2. Anticoagulation and Cannulation
•Administer heparin (300–400 IU/kg) if not pre-administered.
•Cannulate:
•Ascending aorta
•Right atrial appendage (for venous drainage)
•Vent left ventricle via right superior pulmonary vein if needed.
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3. Normothermic Regional Perfusion (if institutional protocol allows)
(Optional – some centers proceed directly to cold arrest)
•Initiate NRP:
•Clamp arch vessels (innominate, LCCA, LSA)
•Reperfuse heart with oxygenated blood
•Assess:
•Cardiac rhythm
•Contractility
•Lactate trends
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4. Aortic Cross-Clamp and Cardioplegic Arrest
•Cross-clamp ascending aorta.
•Administer cold blood cardioplegia (antegrade).
•Topical ice slush applied.
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5. Heart Explantation
1.Divide:
•IVC
•SVC
2.Transect:
•Pulmonary artery (long segment preserved)
•Ascending aorta (proximal clamp site)
3.Open left atrium with generous cuff.
4.Remove heart and place immediately on sterile back table.
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V. TRANSMEDICS OCS HEART SETUP
1. Back Table Preparation
•Trim vessels:
•Aorta (shortened, reinforced)
•Pulmonary artery aligned with inflow cannula
•Cannulate:
•Aorta → arterial inflow
•Pulmonary artery → venous return
•Secure with heavy silk ties.
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2. Initiation of OCS Perfusion
•Connect heart to OCS circuit.
•Begin perfusion with:
•Warm, oxygenated donor blood
•Target perfusion pressure: 65–85 mmHg
•Rewarm gradually.
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3. Functional Assessment on OCS
•Monitor:
•Aortic pressure
•Coronary flow
•Lactate clearance (arterial vs venous)
•Visual contractility
•Acceptable trends:
•Declining lactate
•Stable sinus rhythm
•No ventricular distention
LUNG PROCUREMENT
1. Ventilation and Recruitment
•Resume low tidal volume ventilation:
•TV 6–8 mL/kg
•PEEP 5–8 cm H₂O
•Perform recruitment maneuver.
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2. Pulmonary Flush
•Cannulate main pulmonary artery.
•Vent left atrium.
•Administer cold low-potassium dextran solution (Perfadex):
•60–70 mL/kg
•Apply topical lung cooling.
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3. Lung Explantation
1.Divide trachea with inflated lungs.
2.Divide pulmonary veins with generous LA cuff.
3.Remove lungs en bloc or separately.
4.Place in cold preservation solution.
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VII. EX VIVO LUNG PERFUSION (EVLP)
1. EVLP Circuit Setup
•Lungs connected to EVLP circuit.
•Perfusate:
•Steen solution ± packed RBCs
•Temperature:
•Gradual rewarming to 37°C
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2. EVLP Protocol
•Low-flow perfusion initially.
•Protective ventilation:
•TV 6–7 mL/kg
•PEEP 5 cm H₂O
•Monitor:
•Pulmonary vascular resistance
•Compliance
•PaO₂/FiO₂ ratio
•Bronchoscopy findings
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3. Lung Assessment and Reconditioning
•Treat:
•Atelectasis
•Pulmonary edema
•Secretions
•Reassess suitability for transplant.
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VIII. TRANSPORT AND IMPLANTATION
Heart
•Remains perfused on TransMedics OCS until recipient ready.
•Minimal cold ischemia at implantation.
Lungs
•Transplanted directly post-EVLP or stored briefly cold if needed.
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IX. KEY QUALITY METRICS
•Functional warm ischemia time
•Lactate clearance on OCS
•EVLP oxygenation improvement
•Total preservation time
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X. FINAL NOTES
•DCD heart and lung recovery requires:
•Precise timing
•Multidisciplinary coordination
•Advanced perfusion technology
•TransMedics OCS and EVLP expand donor utilization while preserving outcomes.
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.
