Lung transplantation

The lung transplantation center at the University Hospital Zurich belongs to the most modern hospitals with specialization on lung diseases in Switzerland. For most surgical indications today the bilateral lung transplantation is performed. It replaces the heart-lung transplantation applied in pioneer times of lung transplantation. As of October 2014 433 lung transplantations have been performed in Zurich.

The lung transplantation is an established therapy in advanced lung diseases, such as cystic fibrosis, lung fibrosis, chronic obstructive lung diseases and alpha-1-antitrypsin deficiency, pulmonal arterial hypertension as well as additional, incurable or rare lung diseases such as lymphangioleiomyomatosi, histiocytosis X and sarcoidosis. The lung transplantation as surgical therapy increases the survival rate and leads to a particularly increased quality of life.

Film in Puls-TV (SRF) from 16.5.2011: A large donor lung for two recipients.

The first single-lung transplantation was successfully performed in 1983 in Toronto, Canada (the patient survived seven years). In 1985 the first double lung transplantation was performed (the patient survived 16 years). In Switzerland the first lung transplantation was performed in November 1992 in Zurich (Fig. 1-3). In Switzerland there are two lung transplantation centers, Zurich and Geneva, whereas the surgical part of the therapy has been removed from Geneva to Lausanne since 2004.

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Fig. left: Before lung transplantation.
Fig. right: After lung transplantation.


Donation from brain dead donors are currently the standard in lung transplantation. Because of the increasing lack of organs the living donation has been developed and introduced. But it is limited to just a few experienced centers (in Japan and USA).

Who receives a transplantation

Lung transplantation is indicated in advanced stage lung disease when conservative therapy options are failed. In this phase patients suffer already from dyspnea (respiratory distress) with little exertions, are very limited concerning their life quality and estimated life expectancy is less than two years.
In patients with systemic attendant symptoms, with a malignancy or a sepsis (blood poisoning), a generalized arteriosclerosis, kidney or liver insufficiency or with less favorable psychosocial factors, a nicotine, alcohol or drug addiction or if they are over 65 years old, a lung transplantation is not indicated (accord. to international directives).

Disease types

Cystic fibrosis
Cystic fibrosis as a systemic illness affects different organs, among others the upper and lower respiratory airways, liver, pancreas and gastro-intestinal tract. Often patients are contaminated with multi-resistant germs at the time of lung transplantation.
Due to improvements in the peri- and postoperative care cystic fibrosis has the best results after transplantation in experienced centers. Referral  to the transplantation center should be made early, in particular before the patients significantly and irreversibly lose weight due to the advancing underlying disease and are thus weakened and without muscle power.

Chest ct scan: obvious bronchiectasis in cystic fibrosis.
Chest ct scan: obvious bronchiectasis in cystic fibrosis.

Chronic obstructive pulmonary disease(COPD) (including alpha-1-antitrypsin deficiency)
Worldwide COPD is among the most frequent indication for a lung transplantation. So this disease is on the one hand very frequent, but on the other hand COPD patients have a favorable prognosis on the transplantation waiting list compared to patients with another underlying disease. Basically for these patients a uni- or bilateral transplantation is possible. Although the surgery time for unilateral lung transplantation is shorter the remaining residual lung is a risk for later complications. The functional results and the long-term survival are better after bilateral lung transplantation, this is the reason why we in Zurich prefer the bilateral lung transplantation.  

Lung fibrosis
Lung fibrosis often shows a quick decline of the pulmonary function parameters quickly after the diagnosis and the affected patients often come too late to prior assessment  for transplantation. They are dying while on the transplantation waiting list from the rapidly progressive underlying disease or from the effects of the (in most cases unsuccessful) immuno-suppressive therapy. Patients suffering from lung fibrosis should be referred as fast as possible to our transplantation center at the University Hospital Zurich. The waiting time for patients amounts in most cases 6 to 12 months. But this can also take just a few days or years depending on whether or not a suitable donor lung is available. 
                            
Transplant Center at the University Hospital Zurich

Pulmonary hypertension
Both the primary and the secondary pulmonary hypertension are good transplantation indications (disease characterized by increase of vascular resistance, blood pressure increase in the lung circulation and often following right-heart-insufficiency). After the lung transplantation the right heart recovers completely within a few weeks.
With the emerging of intravenously administered and inhaled, potent medication the indication for lung transplantation with this disease became rarer. Only for those patients who are not responding to medical therapy transplantation is still indicated today. Nevertheless it is recommended to refer these patients with the diagnosis of pulmonary hypertension at the transplantation center, to make sure that the right time for the inclusion in the waiting list is not missed.                                 

Incurable or rare lung diseases
Lung transplantation can be performed with success for additional, rare lung diseases. For example in cases of lymphangioleiomyomatosis (cystic lung disease characterized by a diffuse non-malignant proliferation of smooth muscle fibers in the lymphatic capillary walls): histiocytosis X (lung disease that affects the smallest branching of the respiratory system (bronchioli) and sarcoidosis (granulomatous inflammation that generally can affect each organ, but in most cases it affects the lung).

Surgical procedure

The unilateral-lung transplantation is usually performed in patients with a COPD or lung fibrosis. Thereby the rib cage is opened by means of a posterolateral or antero-lateral  thoracotomy (lateral cut along the rib), the affected lung is removed and donor lung is sewed to the prepared main bronchus and the pulmonary artery and the pulmonary vein, as well as the left atrium. During the surgery the healthy, contralateral lung is artificially ventilated.

During transplantation for  COPD hypoxemia (oxygen insufficiency in the blood) or hemodynamic instability (instable blood flow) may occurs rarely, in this case using a heart-lung machine is used. In contrast this is quite often the case at primary pulmonary hypertension or in patients with lung fibroses and secondary pulmonary hypertension.


                             


 


 


 


 


 


 


 

The implantations of the lung it is started with bronchial anastomosis.

At the bilateral lung transplantation- more frequent in patients with cystic fibrosis - the access was performed until end of 2000 by means of a transversal thoracosternotomy, the so-called clamshell incision. In many cases today the sternal split - with higher complication rate after transplantation - can be avoided and the access is performed over a bilateral anterolateral (on the front and the sides) thoracotomy. And if necessary the heart-lung machine can be used as well.

At the combined heart-lung-transplantation – currently performed rarely and is mainly reserved for patients with congenital heart diseases and Eisenmenger's syndrome developments – the surgery is performed over a transversal thoracosternotomy or a median sternotomy (longitudinal cut of the sternum). The two organs are transplanted en bloc. Technically the operation is easier than the isolated lung transplantation. But if previous operations have already taken place, it can significantly complicate than the isolated lung transplantation. The connection of airways is performed as tracheal anastomosis, the aorta ascendens of the donor is connected with the recipient's and the right atrium is connected as atrium anastomosis. The surgery takes place by use of the heart-lung-machine.

Improved results
 In the last twenty years the lung transplantation developed from an experimental to an established therapy in patients with advanced lung diseases. Increased experience and improved  surgical techniques, anesthesia, intensive care monitoring and advances in the immuno-suppressive treatment, prevention of infections led to improved results

Compared to theearly days of lung transplantation the one-year survival rate significantly increased. In international comparison the current rates amount 80% - whereas they have been at 62% in the years from 1988 - 1992. In contrast the five-year survival remained globally the same at 45%, what mainly depends on the fact that the chronic rejection of the implant is still high. The rates in Zurich are 80% for one-year survival, 65% for five-year survival and 50% for twelve-year survival.

Treatment and risks after TPL

The procedure of lung transplantation is nowadays considered as established and save therapy. The time after the transplantation is more critical. For long-term survival the specific and consequent treatment of any occurring inflammatory risks after transplantation is decisive [10]. This is because unlike to other implanted solid organs such as the heart, liver or kidney the transplanted lung is exposed to many noxious agents (chemical substances and physical influences), what is the main reason for increasingly higher occurring chronic rejection reaction to the transplant compared to other organs. The immune reaction of implanted patients is suppressed; dangerous germs can easily intrude into the organism and spread there. Risk factors for the chronic rejection reaction of transplants are allo-immune related (e.g. acute rejection) but also non-allo-immune related (e.g. virus, reflux of chyle into esophagus, fungi, organic and inorganic pollutants in the outside air etc.).

Strict follow-up and further treatment
The management after the transplantation heavily complies with early detection of possible defects or acute rejections of the implanted lung, as the body is seeing the new lung as foreign tissue. By means of invasive and non-invasive methods such as bronchoscopies, bronchoalveolar lavage and transbronchial lung biopsy the condition of the transplant is checked regularly. And the recommended pulmonary function tests (spirometry) can also be performed by the patient at home.

AMaechler_ZystFibrose_TPL.png AMaechler_Zyst_Fibrose_TPL.png This patient suffers from a cystic fibrosis. This disease limited her life quality significantly, why she received permanent oxygen therapy. In 2002 she was 16 years old, when we performed lung transplantation on both sides. Since then the young woman comes regularly for medical examination into the University Hospital Zurich. She has a very good overall condition. This picture shows the patient before her transplantation and ten years later during a motorcycle tour with her father.

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Ex vivo lung perfusion (EVLP)

There is still a lack of suitable donor lungs for patients who need a lung transplantation. Since 2012 donor lungs are thus at our department after a standard extraction procedure connected to an ex vivo lung perfusion system and mechanically ventilated, similar to a heart-lung machine, for evaluation and optimization purposes. Lungs, which couldn't have been used for a transplantation before improve their organ function in this system for a subsequent successful transplantation.
 
Due to the ex vivo lung perfusion the number of available donor organs increases significantly.

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Ex vivo Lung Perfusion (ELVP)