(Transplant-Lung, Lung Transplant, Lung Graft)
What is a lung transplant?
A lung transplant is a surgical procedure performed to remove one or both diseased lungs from a patient and replace it with a healthy one from another person. The majority of lungs that are transplanted come from deceased organ donors. This type of transplant is called a cadaveric transplant. Healthy, nonsmoking adults who make a good match may be able to donate a part (a lobe) of one of their lungs. This type of transplant is called a living transplant. Individuals who donate a part of a lung can live healthy lives with the remaining lung tissue.
Various types of lung transplant procedures include single lung (transplantation of one lung); double lung, bilateral sequential, or bilateral single (transplantation of two lungs); and heart-lung transplants (transplantation of both lungs and the heart taken from a single donor). The type of procedure performed depends on the condition of the recipient.
Anatomy of the lungs
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The respiratory system is made up of the organs involved in the exchange of gases--primarily of oxygen and carbon dioxide--and consists of the:
The upper respiratory tract includes the:
- Nasal cavity
- Ethmoidal air cells
- Frontal sinuses
- Maxillary sinus
The lower respiratory tract includes the lungs, bronchi, and alveoli.
What are the functions of the lungs?
The lungs take in oxygen, which cells need to carry out their normal functions. The lungs also get rid of carbon dioxide, a waste product of the body's cells.
The lungs are a pair of cone-shaped organs made up of spongy, pinkish-gray tissue. They take up most of the space in the chest, or the thorax (the part of the body between the base of the neck and diaphragm).
The lungs are enveloped in a membrane called the pleura.
The lungs are separated from each other by the mediastinum, an area that contains the following:
- The heart and its large vessels
- Trachea (windpipe)
- Lymph nodes
The right lung has three sections called lobes. The left lung has two lobes. When you breathe, the air enters the body through the nose or the mouth. It then travels down the throat through the larynx (voice box) and trachea (windpipe) and goes into the lungs through tubes called mainstem bronchi.
One mainstem bronchus leads to the right lung and one to the left lung. In the lungs, the mainstem bronchi divide into smaller bronchi and then into even smaller tubes called bronchioles. Bronchioles end in tiny air sacs called alveoli.
A lung transplant may be recommended for people who have serious lung dysfunction that cannot be improved with maximal medical therapy and whose life expectancy without a transplant is 12 to 24 months. Lung transplants may be performed on all ages from newborn to adult, generally up to age 65.
A lung transplant may be performed for the following conditions:
- Severe cystic fibrosis (CF). An inherited disease characterized by an abnormality in the glands that produce sweat and mucus. It is chronic, progressive, and is usually fatal.
- Bronchopulmonary dysplasia or chronic obstructive pulmonary disease (COPD). A term that refers to a group of lung diseases that can interfere with normal breathing.
- Pulmonary hypertension. Increased pressure in the arteries of the lungs.
- Heart disease or heart defects affecting the lungs. These may require a heart-lung transplant.
- Pulmonary fibrosis. Scarring of the lungs.
- Some hereditary conditions affecting the lungs
- Other diseases causing severe lung damage. These include sarcoidosis, histiocytosis, and lymphangioleiomyomatosis.
However, not all cases of these conditions require lung transplantation. A lung transplant is not recommended as a treatment for lung cancer.
There may be other reasons for your doctor to recommend a lung transplant.
As with any surgery, complications may occur. Some complications from lung transplantation may include, but are not limited to, the following:
- Blockage of the blood vessels to the new lung(s)
- Blockage of the airways
- Severe pulmonary edema (fluid in the lung)
- Blood clots
The new lung may be rejected. Rejection is a normal reaction of the body to a foreign object or tissue. When a new lung is transplanted into a recipient's body, the immune system reacts to what it perceives as a threat and attacks the new organ, not realizing that the transplanted lung is beneficial. To allow the transplanted organ to survive in a new body, medications must be taken to trick the immune system into accepting the transplant and not attacking it as a foreign object.
The medications used to prevent or treat rejection have side effects. The exact side effects will depend on the specific medications that are taken.
Contraindications for lung transplantation include, but are not limited to, the following:
- Current or recurring infection that cannot be treated effectively
- Metastatic cancer, which is cancer that has spread from its primary location to one or more additional locations in the body
- Severe cardiac or other medical problems preventing the ability to tolerate the surgical procedure
- Serious conditions other than lung disease that would not improve after transplantation
- Noncompliance with treatment regimen
There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor prior to the procedure.
If you are going to receive a lung from an organ donor who has died (cadaver), you will be placed on a waiting list of the United Network for Organ Sharing (UNOS.) The average person waits around two years for a single lung transplant, and as long as three years for two lungs. People who are unable to wait that long may be considered for lung transplant from a living donor.
Because of the wide range of information necessary to determine eligibility for transplant, the evaluation process is carried out by a transplant team. The team includes a transplant surgeon, a transplant pulmonologist (doctor specializing in the treatment of the lungs), one or more transplant nurses, a social worker, and a psychiatrist or psychologist. Additional team members may include a dietician, a chaplain, and/or an anesthesiologist.
Components of the transplant evaluation process include, but are not limited to, the following:
- Psychological and social evaluation. Psychological and social issues involved in organ transplantation, such as stress, financial issues, and support by family and/or significant others are assessed. These issues can significantly impact the outcome of a transplant.
- Blood tests. Blood tests are performed to help determine a good donor match and to help improve the chances that the donor organ will not be rejected.
- Diagnostic tests. Diagnostic tests may be performed to assess your lungs as well as your overall health status. These tests may include X-rays, ultrasound procedures, computed tomography (CT scan), pulmonary function tests, lung biopsy, and dental examinations. Women may receive a Pap test, gynecology evaluation, and a mammogram.
- Other preparations. Several immunizations will be given to decrease the chances of developing infections that can affect the transplanted lungs. In addition, lung transplant recipients who smoke must quit smoking and be nicotine-free for several months before being put on the transplant list.
The transplant team will consider all information from interviews, your medical history, physical examination, and diagnostic tests in determining your eligibility for lung transplantation.
Once you have been accepted as a transplant candidate, you will be placed on the UNOS list. When a donor organ is available, lung recipients are selected based on blood type, geographic location (distance between donor and recipient), and lung allocation score. This score is based on medical urgency rather than length of time on the waiting list. You will be notified and told to come to the hospital immediately so you can be prepared for the transplant.
If you are to receive a lung from a living donor, the transplant may be performed at a planned time. The potential donor(s) must have a compatible blood type and be in good health. A psychological test will be conducted to ensure the donor is comfortable with the decision.
The following steps will precede the transplant:
- Your doctor will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.
- You will be asked to sign a consent form that gives your permission to do the surgery. Read the form carefully and ask questions if something is not clear.
- For a planned living transplant, you should fast for eight hours before the operation, generally after midnight. In the case of a cadaver organ transplant, you should begin to fast once you are notified that a lung has become available.
- You may receive a sedative prior to the procedure to help you relax.
- Based on your medical condition, your doctor may request other specific preparation.
Lung transplantation requires a stay in a hospital. Procedures may vary depending on your condition and your doctor’s practices.
Generally, a lung transplant follows this process:
- You will be asked to remove any jewelry and other objects that may interfere with the procedure.
- You will be asked to remove clothing and will be given a gown to wear.
- An intravenous (IV) line will be started in your arm or hand. Additional catheters will be inserted in your neck and wrist to monitor the status of your heart and blood pressure, as well as for obtaining blood samples. Alternate sites for the additional catheters include the subclavian (under the collarbone) area and the groin.
- You will be taken to the operating room and positioned on a table. Your position will depend on the type of procedure to be performed. For a single lung transplant, you will be positioned on the side opposite the side of the transplant. For a bilateral sequential lung transplant, you will be lying on your back with your arms above your head.
- A catheter will be inserted into your bladder to drain urine.
- If there is excessive hair at the surgical site, it may be clipped off.
- Lung transplant surgery will be performed while you are asleep under general anesthesia. A tube will be inserted through your mouth into your lungs. The tube will be attached to a ventilator that will breathe for you during the procedure.
- The anesthesiologist will continuously monitor your heart rate, blood pressure, and blood oxygen level during the surgery.
- The skin over the surgical site will be cleansed with an antiseptic solution.
- The doctor will make an incision in the chest. For a single lung transplant, the incision will be made on the side of the lung to be transplanted. For a bilateral sequential transplant, the incision will be made horizontally across the chest below the breasts.
- The diseased lung(s) will be carefully removed and replaced by the donor lung(s). Depending on your underlying lung condition and the type of transplant being performed, you may be placed on a cardiopulmonary bypass machine (heart-lung machine) to maintain circulation and provide oxygen to the body during the procedure.
- The new lung’s blood vessels and airways will be attached. For a bilateral sequential transplant, the lungs will be attached one at a time.
- The incision will be closed with sutures or surgical staples.
- A sterile bandage or dressing will be applied to the incision.
- One or more chest tubes will be placed in the chest to remove air, fluid, and blood from the surgical site and to allow the new lung(s) to expand fully.
- An epidural catheter to infuse pain medication into your back may be inserted before you leave the operating room.
In the hospital
After the surgery you may be taken to the recovery room before being taken to the intensive care unit (ICU) to be closely monitored for several days. Alternately, you may be taken directly to the ICU from the operating room. You will be connected to monitors that will constantly display your electrocardiogram (ECG or EKG) tracing, blood pressure, other pressure readings, breathing rate, and your oxygen level. Lung transplant surgery requires an in-hospital stay of seven to 14 days, or longer.
You will have a tube in your throat so that your breathing can be assisted with a ventilator until you are stable enough to breathe on your own. The breathing tube may remain in place for a few hours up to several days, depending on your situation.
You may have a thin, plastic tube inserted through your nose into your stomach to remove air that you swallow. The tube will be removed when your bowels resume normal function. You will not be able to eat or drink until the tube is removed.
Blood samples will be taken frequently to monitor the status of the new lung(s), as well as other body functions, such as the kidneys, liver, and blood system.
You may be on special IV drips to help your blood pressure and your heart, and to control any problems with bleeding. As your condition stabilizes, these drips will be gradually weaned down and turned off as tolerated.
You may receive pain medication as needed, either by a nurse, through an epidural catheter, or by administering it yourself through a device connected to your intravenous line.
Once the breathing and stomach tubes have been removed and your condition has stabilized, you may start liquids to drink. Your diet may be gradually advanced to more solid foods as tolerated.
Your immunosuppression (anti-rejection) medications will be closely monitored to make sure you are receiving the optimum dose and the best combination of medications.
Nurses, respiratory therapists, and physical therapists will work with you as you begin physical therapy and breathing exercises.
When your doctor feels you are ready, you will be moved from the ICU to a private room on a regular nursing unit or transplant unit. Your recovery will continue to progress here. Your activity will be gradually increased as you get out of bed and walk around for longer periods of time. Your diet will be advanced to solid foods as tolerated.
Nurses, pharmacists, dietitians, physical therapists, and other members of the transplant team will teach you how to take care of yourself once you are discharged from the hospital.
Once you are home, it will be important to keep the surgical area clean and dry. Your doctor will give you specific bathing instructions. The sutures or surgical staples will be removed during a follow-up office visit, if they were not removed before leaving the hospital.
You should not drive until your doctor tells you to. Other activity restrictions may apply.
Follow-up visits will be scheduled frequently after returning home from the hospital. These visits may include blood tests, pulmonary function tests, chest X-ray, bronchoscopy (examination of the main airways of the lungs using a long, thin tube that has a close-focusing telescope on the end for viewing) and biopsy (removal of tissue from the lung for examination under a microscope). The transplant team will explain the schedule for these tests. The rehabilitation program will continue for many months.
Notify your doctor to report any of the following:
- Fever and/or chills (may be a sign of infection or rejection)
- Redness, swelling, or bleeding or drainage from the incision site
- Increase in pain around the incision site
- Difficulty breathing
Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.
To allow the transplanted lung(s) to survive in your body, you will be given medications for the rest of your life to fight rejection. Each person may react differently to medications, and each transplant team has preferences for different medications. The anti-rejection medications most commonly used include:
- Mycophenolate mofetil
New anti-rejection medications are continually being approved. Doctors tailor medication regimes to meet the needs of each individual patient.
Usually, several anti-rejection medications are given initially. The doses of these medications may change frequently, depending on your response. Because anti-rejection medications affect the immune system, people who receive a transplant will be at higher risk for infections. A balance must be maintained between preventing rejection and making you very susceptible to infection.
Some of the infections you will be especially susceptible to include oral yeast infection (thrush), herpes, and respiratory viruses. You should avoid contact with crowds and anyone who has an infection for the first few months after your surgery.
The following are some of the most common symptoms of rejection. However, each individual may experience symptoms differently. Symptoms may include:
- Fluid collection in the lung
- Decreased oxygen level in the blood
- Shortness of breath
The symptoms of rejection may resemble other medical conditions or problems. Consult your transplant team with any concerns you have. Frequent visits to and contact with the transplant team are essential.