Pros and Cons of Artificial Organs
The need for transplant organs outnumbers the supply of available organs. There are many reasons and chronic disease processes that would necessitate a transplant. In the case of lung transplants, the “number of donors has not kept up with the demand for transplantable organs” (Sato MD, et al., 2007, p. 988). There is no reliable continuous supply of organs and there is no cure for the diseases and injury’s we will continue to encounter as humans. Therefore we are forced to look elsewhere in an effort to meet the need. Some of these needs are temporary in treating the disease process, some a bridge to a solution and some are the permanent solution.
As with any procedure, there are pro’s and con’s to artificial organs. Ethically and physiologically there are many angles to consider before consenting to an artificial organ. If we look at the area of the artificial heart, we know the patient is in critical need. “Heart failure is the leading cause of death in much of the developed world” (Keen, 2000). Keen (2000) also goes onto describe how “cardiac transplantation can only meet the needs of a relatively small number of patients” and “even if the availability of donor hearts increases, it is unlikely that donor availability will keep pace with the escalating prevalence of end-stage heart failure”. This patient’s natural heart may be failing or perhaps they have been put on the heart-lung machine and are unable to stabilize enough to come off this machine. The largest benefit of the artificial heart is the availability, with a supply that is unable to meet the need; the artificial heart is the only solution. Many of the candidates have an end of life trajectory that is only a few months and some of them would otherwise not be candidates for heart transplantation. The ultimate benefit of the left ventricular assist device (LVAD) is to prolong survival and improve the quality of life. It is the hope that the LVAD will strengthen the heart function and increase perfusion to the vital organs increasing energy and prolonging life and quality of life (Rizzieri, Verheijde, Rady, & McGregor, 2008). The device allows the patient to recuperate and wait at home for a donor heart until one comes available, without the use of artificial device, as many as 40% of patients on the transplant list will die while waiting (Keen, 2000). Some facilities have had success as high as 85% survival rates among patients since 2006 (Weekly, 2010). The insertion of the LVAD will on average add 12 – 24 months to the lives of the patient, increasing the quality of life and allowing for some time away from the hospital settings as pt are often able to go home to wait for a donor, palliate or recover (Rizzieri, Verheijde, Rady, & McGregor, 2008).
While there are many benefits to the patient receiving the artificial heart, there are always cons to consider. Some critics feel that the patient in need of the artificial heart is in no position to make a conscious decision about receiving an artificial heart as the outcome is mortality. Those who believe this to be true use the Nuremberg Code, which was designed to protect “human subjects during experimental research trials” (Simmons, Fall and Winter 2001, p. 402). The fear is also that death or disabling injury will result from the experimental nature of the transplant of the artificial heart. This may be one of the ethical issues against artificial hearts, though there are many complex issues to examine also to consider is the fact that the heart is more than just a beating pump or organ, the heart is symbolic in life itself. Among other issues of the artificial heart are those of caregiver burden. The emotional, financial and social strain put on those individuals in immense. The caregiver must be on call virtually at all times, trained to respond to emergencies and know when to seek help. The caregivers are often in a situation where they worry more about the device then do the patients themselves. Rizzieri, 2008 also notes that “Caregivers of survivors on mechanical ventilators experience severe depression, anxiety, and posttraumatic stress disorders lasting as long as 12 months” (Rizzieri, Verheijde, Rady, & McGregor, 2008). Financial burden should also be considered when looking at hospital visits, travel and lost wages of the patient and caregiver (Rizzieri, Verheijde, Rady, & McGregor, 2008).
There are also many physical complications that go with the artificial heart; the patient is prone to infections and device malfunction. The LVAD is surgically implanted and requires a 30-90 day post-op period in which there is a mortality rate of 14 – 27%. Post insertion of the LVAD, the most common complication is infection, whether it is local or systemic. This patient population will be at increased mortality, which may in turn decrease the quality of life. Over time the device may be predisposed to malfunctions such as tears or weakening of the device (Rizzieri, Verheijde, Rady, & McGregor, 2008). Rizzieri also notes that the patient is at an increased risk of stroke, wheatear it is embolic or hemorrhagic in nature, and this is directly related to the length of time the patient is on the LAVD. Also related to the length of time the patient is on the device is the risk of cognitive impairment or brain damage associated with the frontal lobe. One model of the artificial heart called the Abircor, weighs about 2 lbs and has a portable driver that weighs an additional 13.5 lbs. The Abiocor has a battery pack that is strapped to the chest (Simmons, Fall and Winter 2001). All in all there is an incredible about of material to digest and decide upon for the patient of the artificial heart and their family.
There are other artificial organs such as the kidney. The artificial kidney is dialysis; it is a membrane which cleanses the blood of waste products. This dialysis treatment is very good at quickly and efficiently resolving the symptoms of uremia. Among the benefits of the artificial kidney is the ability for the patient to gain years of life they would not otherwise have. Van Noordwijk, 2001 estimates that “more than half a million people around the world would be living on long-term dialysis”. Once the patient is stabilized onto a dialysis program; they are often able to get this care close to home through a satellite center. This enables the patient o have a life outside of the hospital and only need daycare type of arrangements for treatments (The Kidney Foundation of Canada 2009).
The artificial kidney has some drawbacks; dialysis may take from 4 – 8 hrs three times a week. During this time the patient must be hooked up to the machine making all other activities revolve around the dialysis schedule. These patients must follow a strict regimen of medications, dietary changes and fluid restrictions. Without compliance the treatments are not effective. They must have reliable venous access and be educated as to the care involved in maintain these lines, obtaining theses lines is sometime a challenge and not possible in these patients. Though there are many satellite centers for dialysis, depending on the area, the patient and possibly the family may have to travel some distance for these treatment, this could involve travelling on some treacherous roads due to our Canadian winters (The Kidney Foundation of Canada, 2009).
Another con to consider when examining dialysis is the ethical dilemmas involved. As we are now able to prolong the lives of patients with chronic renal disease, the issue of stopping or continuing treatment arises. When the outcome of stopping the dialysis treatment is ultimately death, the question arises as to what are the criteria or protocol for stopping treatment? A further ethical dilemma within this patient group is whether or not to resuscitate in event of cardiac or respiratory arrest (Hermsen & van der Donk, 2009).
While there has been success in the artificial heart and kidney, the artificial lung has not shared the same success. “In contrast to advances in the development of cardiac or renal support systems for adults, the development of extra-, Para- and intracorporeal mechanical systems for acute or chronic lung respiratory failure has lagged far behind” (Go & Macchiarini, 2008). ECMO is one example of artificial lung options; it describes prolonged extra-corporeal cardiopulmonary bypass. Like the trend in most organ transplant list, the need has increased steadily during the last decade (Sato MD, et al., 2007). “The only current treatment for chronic irreversible pulmonary failure is lung transplantation” (Zwishenberger & Alpard, 2002, p. 253). Some of the cons when considering the issue of artificial lung are the increasing amount of patients with end-stage pulmonary disease. Due to the difficulties in science to master the artificial lung, mechanical ventilation has been the treatment option which carries many risks itself. Some of the treatments needed in conjunction with ECMO are continuous anticoagulation with heparin to prevent thrombosis (Zwishenberger & Alpard, 2002). Though there have been some success with the artificial membrane for oxygenation these patients still face many difficulties. Some of the treatments that these patients will need include multiple blood transfusions labour intensive therapy and risk of infection (Go & Macchiarini, 2008). If we look at the ECMO specifically the patient requires “multiple transfusions and is complex, labour-intensive, time-limited, costly, non-ambulatory and prone to infection” (Zwishenberger & Alpard, 2002, p. 253). The success rate and difficulties/ complications encountered with the artificial lung have kept the market small and investment minimal. Japan has had recent interest and success in the percutanous cardiopulmonary support (PCPS). The durability of the PCPS is days to weeks, creating restrictions in its use. Again market desire needs and investment and the technical/medical obstacles have kept the artificial lung from advancing to the next stage of becoming an option or bridge to lung transplant (Nogawa, 2002).
When looking at the pros for artificial lungs the thoracic artificial lung (TAL) is an area where some benefits has been achieved. There has been some success in 7-day trials in treatment for acute respiratory insufficiency that is unresponsive to mechanical ventilation but improvements in blood biocompatibility are warranted (Sato MD, et al., 2007). Wth ECMO some of the conditions treated with success have been “bacterial and viral pneumonias, fat and thrombotic pulmonary embolism, thoracic and extra thoracic trauma, shock, sepsis and near-drowning” (Zwishenberger & Alpard, 2002, p. 256). These successes have been limited to short term use of the ECMO for up to 3 weeks. Ultimately the success has been dependent on identifying the cause of the repertory failure and trying to reverse it within the timeframe that the patient needs the ECMO (Zwishenberger & Alpard, 2002). Again even with the limited success of the ECMO and other options of the artificial lung “The current methods for supporting patients with lung disease, however, are not adequate or efficient enough to act as a bridge to transplantation (Zwishenberger & Alpard, 2002, p. 261).
In Conclusion, there have been many advances in the field of artificial organs, saving many lives. There are unfortunately pros and cons associated with each organ, all of which must be considered prior to treatment. Some ethical issues will also come into play as the patient population needing the organs usually have end stage disease or are critically ill limiting their options. All in all a complex issue that will continue to evolve as new treatment options are developed.
This You Tube video is a quick look at a artificial organ created by SynDaver Labs.