Lung Transplant | Doctors & Surgery Information

A lung transplant is a surgical procedure in which part or all of a new, healthy lung is implanted into the body. The diseased lung or diseased portions of the lung must be removed. A lung transplant is necessary for some end-stage lung diseases. In these cases, no other treatments are effective, and the last hope is a new lung from a healthy donor.

In some cases, it is sufficient to replace only parts of a lung; however, a completely new lung is often necessary. In most cases, the donor lung comes from a deceased donor; in rare cases, living donations can be performed. In the latter case, parts of a healthy lung are donated, and the donors are, without exception, close family members.

Sometimes the lung disease also affects the heart. In some rare cases, a combined heart and lung transplant must then be performed. Nowadays, a combined transplant is rarely necessary, as much of the damage to the heart reverses once the lungs are functioning normally again. In most cases, a simultaneous heart and lung transplant is performed only if the patient also has a heart defect.

Since the lungs are in constant contact with the outside world through the inhalation of air and are therefore exposed to all kinds of harmful substances and pathogens, there are numerous diseases that can affect them. If severe enough, these can ultimately lead to a deterioration in lung function and even the need for a transplant. The most important conditions are listed below:

• Chronic obstructive pulmonary disease (COPD), also commonly referred to as “smoker’s lung”
• Pulmonary fibrosis (a disease characterized by scarring and hardening of the lung’s connective tissue, often resulting from long-term COPD)
• Cystic fibrosis (a metabolic disorder affecting the lungs and other organs)
• Hypersensitivity pneumonitis or exogenous allergic alveolitis (inflammatory changes in the alveoli caused by inhaling organic dusts)
• Pulmonary hypertension (high blood pressure in the pulmonary circulation)
• Cortisone-resistant pulmonary sarcoidosis (an inflammatory disease of the lungs with tissue changes)
• Pulmonary emphysema (destruction of lung tissue due to increased air content)
• Severe lung injuries (e.g., following accidents)
• Bronchiectasis (progressive dilation of the airways and alveoli) 
• Lymphangioleiomyomatosis (hereditary condition characterized by excessive growth of smooth muscle)
• Bronchiolitis obliterans (inflammation and scarring of the alveoli)

Overall, there are not enough suitable donor organs, which is why strict criteria govern their allocation. Consequently, there is a waiting list that determines how donor organs are distributed. The most important factors determining a patient’s position on the waiting list and their priority are how urgently they need a donor lung and what their chances of success are. This includes whether the patient is at high risk without a transplant and has a life expectancy of less than 18 months. A rapid decline in lung function is also a reason for a transplant.

Age is also taken into account, with the upper age limit set at 65 years. However, this limit depends not only on chronological age (i.e., calculated based on the date of birth) but also on the patient’s health and fitness. In the U.S., for example, patients older than 65 also undergo lung transplants at specialized centers. However, special preliminary examinations and risk assessments are required in these cases. Other diseases and pre-existing conditions are also taken into account. A lung transplant is contraindicated, for example, in cases of severe atherosclerosis (hardening of the arteries) or alcohol, drug, or medication abuse.

Until 2012, only lungs from deceased donors were transplanted; since then, living donation has also been possible. However, this carries a significant risk of complications for the donor, so very strict criteria are applied to approve living donation. Furthermore, with living donation, understandably, only a partial lung transplant is possible, meaning that the feasibility and success of a living donation depend on the recipient’s underlying condition.

The exact procedure for a lung transplant naturally depends, in particular, on the underlying disease. Chronic infections such as cystic fibrosis, for example, require a bilateral transplant, whereas for many other lung diseases, a unilateral lung transplant may be sufficient.

The allocation of donor organs is subject to strict criteria. Since lungs are usually donated postmortem (following brain death), two independent physicians must confirm the donor’s brain death. The organs are then removed and transported in coolers to a transplant center. There, the recipient is also prepared for the procedure.

At the start of the operation, an incision is made between the eighth and ninth ribs, through which the diseased lung can be removed. Once the diseased lung has been removed, the donor lung is implanted. It is then connected to all relevant structures, such as the bronchi and blood vessels. In the case of a bilateral lung transplant, the same procedure is then performed on the second lung. The patient’s chest is then closed. Over the next few hours, the patient is weaned off the ventilator and is usually able to transfer from the intensive care unit to a general ward after about three days. The entire hospital stay normally lasts about three weeks, during which the patient also receives physical therapy to facilitate rapid mobilization.

A lung transplant carries the same risks as any other surgery. These include inflammation, bleeding, and an adverse reaction to the anesthetic. Infections following a lung transplant usually manifest as pneumonia. However, sepsis and infections of the gastrointestinal tract, kidneys, urinary tract, or nervous system can also occur. These are usually caused by viruses, but fungi can also be the cause.

In addition, there are also some specific risks associated with lung transplantation. The suture sites of the bronchi and pulmonary vessels may either narrow or split open. Furthermore, the lungs may fail, and the body may reject the new lungs. The body recognizes the new organ as a foreign body and activates its defense mechanisms. Acute rejection reactions can now be effectively suppressed with the help of immunosuppressants.

One of the most serious complications is bronchiolitis obliterans syndrome (BOS). This can be both a reason for a transplant and a condition that develops after the transplant. This is a chronic rejection reaction that causes inflammation of the bronchioles and, as a result, narrowing of the airways. In the worst-case scenario, the rejection reaction can be so severe that the patient needs a new lung, or they will die.

Thorough follow-up care is essential in the initial period after surgery. Weekly follow-up appointments with a doctor are scheduled. The doctor checks blood test results and performs X-rays and ultrasound examinations. It is also particularly important that medication doses are constantly adjusted. Immunosuppressive therapy following a lung transplant can have serious side effects, which is why the dosage must be monitored regularly. To do this, the level of medication in the blood is measured at each visit, and the doctor will adjust the dosage if necessary. If no problems are detected during the follow-up examinations, the interval between appointments can be extended. Even long after the surgery, the patient should continue to attend regular follow-up appointments (about every three months). Otherwise, there is a risk that a chronic rejection reaction will go undetected and therefore remain untreated.