Heart-Lung Transplantation

Cardiopulmonary Bypass (CPB) Machine

Ventilation and Anesthesia Equipment

ECMO (Extracorporeal Membrane Oxygenation) System

Organ Preservation Systems

Patient preparation

Medical Evaluation:

Diagnostic Tests: Electrocardiogram, echocardiogram, cardiac catheterization, pulmonary functioning test, CT scan, MRI, and other imaging.

Blood Tests: To monitor the functioning of various organs, for infection diagnosis or absence, and to match regarding blood type or HLA typing.

Nutritional Assessment: Some steps searches for optimization the patient’s diet; consultation concerning malnutrition or obesity.

Medications: Treatment of symptoms associated with heart and lung failure.

Prophylactic antibiotics or antiviral therapy depending on the agents that are likely to precipitate infection.

Medications for severe pulmonary hypertension or pulmonary hypertension associated with heart diseases.

Oxygen and Ventilation: Supplemental oxygen, if needed, or non-invasive ventilation if needed.

Patient position

Supine Position: The patient is positioned supine, placing them flat on their back, on the operating table. This is a typical position for thoracic surgeries, including heart, lung transplants.

Chest Exposure: A patient is typically placed in a slightly elevated position (Trendelenburg or reverse Trendelenburg) to maximize exposure of the thoracic cavity for surgical procedures and to prevent venous congestion. A sternotomy or clamshell incision is employed, so the patient’s chest must be completely open.

Complete assessment of the condition of the recipient.

Availability of an organ donor with the same blood group, an appropriate size of the organ and low rejection risk.

Donor Organ Procurement: The donor’s heart and lungs are retrieved as a single block.

Special handling by protecting the organs from ischemic injury through cold perfusion solutions and packing in sterile bags.

Recipient Preparation: General anesthesia is given into the patient.

Central venous lines, arterial lines, and a Foley catheter are placed.

The patient is placed on ventilator to promote adequate oxygenation.

Initial Incision and Exposure: The major surgery as median sternotomy is done, which is a straight incision made on the sternum. The anterior thoracic wall is incised, thereby exposing the contents of the chest cavity, that is the heart and the lungs.

Cardiopulmonary Bypass (CPB): The patient is prepared for CPB, during surgery the heart and lung function is replaced by a heart-lung machine. Cannulas are inserted into major vessels to allow blood to be diverted into the machine.

The native lungs and heart are then slowly and meticulously dissected.

Pulmonary artery, aorta, superior vena cava (SVC), inferior vena cava (IVC), trachea are branch out.

Implantation of Donor Organs:

Lung Transplantation: The donor trachea Intervertebral disc is sutured to the recipient trachea Intervertebral disc.

The pulmonary arteries and veins are joined (connected by sutures) to the similar vessels of the recipient.

Heart Transplantation: Donor’s left atrium, right atrium, aorta and pulmonary artery is transected and anastomosed to the corresponding recipient’s structures.

Sequential Anastomoses: The surgical team ensures no more bleeding and perfect seal off at each point of anastomosis that has been done.

Weaning Off Cardiopulmonary Bypass:

Gradual weaning from CPB while monitoring cardiac and pulmonary function.

Administration of medications to support blood pressure and heart rate.

Closure: Chest drains are inserted to evacuate air & fluids.

The sternum is closed then wired, and the skin incision is sutured.

Complications

Infections:
High risk due to immunosuppressive therapy.
Common pathogens: Bacteria (e.g., Staphylococcus aureus), fungi (e.g., Aspergillus), and viruses (e.g., CMV).
Bleeding and Vascular Complications:
Caused by surgical anastomosis or coagulation abnormalities from pre-existing conditions or bypass use during surgery.
Rejection:
Rapid and uncommon; caused by pre-existing antibodies.
Acute cellular or antibody-mediated rejection within days to weeks.
Chronic Rejection (Chronic Graft Dysfunction)
Bronchiolitis obliterans syndrome (BOS): Lung involvement that presents with progressive airflow limitation.
Coronary allograft vasculopathy (CAV): Impacting the heart; it causes ischemic changes.
Infection
Risk continues even later by viral late infections like CMV, EBV, or fungal.
Malignancies
Post-transplant lymphoproliferative disorder (PTLD): It is related to EBV activation.
Skin cancers and other malignancies because of immunosuppression.