WHAT TO EXPECT WHEN CONSIDERING A LUNG TRANSPLANT
“A potential transplant patient will be looked over from the hair on the top of their heads all the way down to their toenails.” —Susan Long, LCSW, Transplant Social Worker at Loyola Hospital, Chicago
As a potential transplant candidate, you will be evaluated by a transplant team which may include: a pulmonologist, transplant surgeon, transplant nurse coordinator, transplant social worker, dietician, psychologist, physical therapist and insurance coordinator. Your physical health, emotional health, and social support system will be closely evaluated.
Eligibility for Lung Transplant
Generally speaking to be eligible for a lung transplant a person should:
- Be in good physical condition besides your lung function
- Be at your ideal body weight
- Have no other life-threatening illnesses
- Demonstrate absolute compliance with prescribed medicines and medical recommendations
- Have a realistic understanding of the emotional implications of a lung transplant
- Have a very supportive social support system in place
- Have participated in pulmonary rehabilitation program
- Expect to participate in educational seminars and a support group
- Consider the financial implications of the procedure/Insurance, etc
Following the Evaluation
Once you have been evaluated and a decision has been made to proceed with a transplant, you will be given a Lung Allocation Score (LAS) based on a variety of factors, including your age, severity of disease, lung, heart and kidney function, and the laboratory values from your tests. This score determines your place on the UNOS (United Network for Organ Sharing) waiting list.
Placement on the Waiting List
Once you have been placed on the transplant list, waiting can be an incredibly stressful time in your life and the lives of your loved ones. Remember to take care of your health, follow your exercise and dietary guidelines, keep up with your pulmonary rehabilitation program, and keep all of your scheduled appointments with your physicians. Transplant centers may offer support groups to individuals awaiting a transplant. It is important that your transplant team can always reach you during this time because you never know when you will receive a call that they have new lungs for you.
Surgery can last anywhere from four to ten hours, depending on several factors including whether it is a single or double lung transplant, your current medical condition, and the institution where the transplant is being performed.
After surgery, your transplant team will manage any post-op challenges that may arise. You will begin taking anti-rejection medications and immunosuppressants, and any side effects or adverse reactions will be closely monitored. Remember everyone will adjust to their new lungs and medications differently.
Before you leave the hospital, make sure you and your caregiver review the following with your transplant team: your medication schedule, follow-up appointments, diet & exercise restrictions, how to safely prepare your home for your arrival, and how to manage your pain.
Remember, a lung transplant is major surgery and it will take some time for you to feel like yourself again. Some transplant recipients will take longer to feel better than others, but do not be discouraged - lean on your support system!
A lung transplant may not be an option for all patients and some may choose to opt out of a lung transplant. Whatever the case, it is crucial to have a support system in place and discuss all of your options with a medical professional.
Ambulatory ECMO as a bridge to transplantation
Extracorporeal membrane oxygenation (ECMO) was adapted from a technique that was employed to oxygenate the lungs during cardiac surgery and has been modified for use in individuals with severely impaired oxygenation (low oxygen levels). Frequently, individuals with impaired gas exchange (removal of carbon dioxide and delivery of oxygen) and low oxygen levels can be effectively supported with mechanical ventilation (respirator). With a respirator, a tube is placed in the main airway (trachea) and oxygen is delivered at a desired concentration and volume. In most situations this method will provide adequate blood oxygen levels. However, in some unusual situations, there is severe respiratory failure (immature lungs in a premature infant, severe bacterial or viral infection, trauma, and other situations) and adequate blood oxygenation cannot be achieved with a mechanical ventilator. In these instances, ECMO has been successfully employed. ECMO was used to treat some individuals with severe viral pneumonia during the H1N1 epidemic.
With ECMO, blood is removed from the body, usually through a large vein, and is then pumped through an artificial membrane which delivers a desired oxygen concentration and removes carbon dioxide. The oxygenated blood is then returned to the body, also usually through a large vein but may also be returned through an artery in the groin. This technique was first employed in the mid-1970s in premature infants with severe respiratory failure, and has been greatly refined and improved since then.
The membranes used to artificially oxygenate the blood are more effective and less injurious to the red cells, and pumping devices have become less traumatic. ECMO has been used to support patients both prior to and following lung transplant surgery. Individuals awaiting transplant can occasionally deteriorate quite rapidly and cannot be adequately oxygenated on a respirator. In these cases, ECMO has been successfully employed for some of these individuals. Following transplant surgery patients can develop acute rejection or primary graft dysfunction (PGD), and in very severe situations ECMO can be used.
One major drawback with standard ECMO techniques is that patients must remain in bed, cannot ambulate, and can become severely deconditioned. Recently techniques have described an ECMO method in which blood is withdrawn and returned through one cannula (a moderate sized tube) placed in a vein in the neck. With this system, the patient can ambulate, eat, and regain some strength. Although this is a relatively new technique, it has been employed in a number of patients who have successfully gone on to lung transplantation.
ECMO is still evolving, is reserved for only the most dire situations, and is not without risk and potential for serious complications. If one looks at the history of artificial organ support systems (kidney dialysis, respirators, heart assist devices), there is an evolutionary process in which these devices are refined, improved, and simplified. It is hoped that there will be continued improvement and development of this life saving technique.
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- Bermudez CA, Adusumilli KR, McCurry KR, et. al. Extracorporeal mem-brane oxygenation for primary graft dysfunction after lung transplantation: long-term survival. Ann Thorac Surg. 2009; 87: 854-860
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Ex Vivo Lung Perfusion - Expanding the donor pool of lung transplantation
Lung transplantation has experienced increasing success, but unfortunately, only a small percentage of patients can benefit from this therapy as a result of the lack of acceptable donor lungs. Lung transplantation could be offered to a larger group of patients if the donor pool could be increased by improving the lung function of the donor lungs that have been deemed unsuitable by existing criteria.
The standard selection criteria for donor lungs from the International Society for Heart and Lung Transplantation (ISHLT) include:
- Age less the 55
- Clear chest X-ray
- Normal oxygen gas exchange
- Absence of chest trauma
- No evidence of aspiration or infection
- Absence of purulent secretions
- Tobacco history of less than 20 years
- ABO blood compatibility
- Appropriate size match with the prospective recipient
This evaluation process can be imprecise and unrecognized injury may lead to early graft dysfunction. It has also been estimated that as many as 30 – 40% of rejected donor lungs could have been safely implanted if appropriate preservation and resuscitation techniques were utilized.
Unfortunately, as a result of the trauma and nature of the injuries that lead to brain death, there are a number of perturbations that occur that can harm the lungs and impair their function. These can include:
- Low blood pressure
- Leaky lung alveoli resulting in pulmonary edema
- Elevated blood sugar
- Low blood pH
- Abnormal kidney function
Additionally the potential donor may have been on a ventilator for several days, and, as result, may have developed an increase in pulmonary secretions. Before explanting the lungs, attempts are made to improve these metabolic and hemodynamic abnormalities.
In order to hopefully improve and adequately assess the lung function of the marginal lungs after they are explanted, they are connected to an ex vivo lung perfusion (EVLP) system. Ex vivo implies that the lungs are perfused outside of the body. This is a complicated process but as simply as possible, the explanted lungs are perfused with a special, dilute blood containing solution that can potentially recondition and improve their function. The apparatus also includes a ventilator to inflate the lungs. This system is quite advantageous in that it: (1) permits the re-expansion of collapsed lung regions; (2) can remove secretions; (3) remove clots from the lung circulation; (4) improve lung ventilation; and (5) permits a better and more complete assessment of lung function.
Using EVLP, institutions in Sweden, Canada, and the United States have transplanted lungs that were initially thought to be unsuitable for transplantation. Results in the studies have revealed no significant difference in outcomes when compared to using standard techniques with suitable lungs. Also these techniques have been employed in individuals who have had cardiac death (i.e. individuals who may not have met the criteria for brain death, but their families have decided to withdraw life support). It has also been postulated that with EVLP, gene therapy could be delivered via the trachea and repair damaged tissue, reduce inflammation, and inhibit rejection.
In summary, EVLP can significantly expand the potential donor pool, improve the function of lungs that might be deemed unsuitable and ultimately decrease inflammation and rejection.
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