Patient selection is the starting point for transplantation . Patients who may benefit from transplantation may be still deemed inappropriate by patient selection committees because of inability to take care of an allograft subsequent to confounding medical and social factors. Patient selection committees are composed of surgeons, physicians experienced in immunosuppression (IS), transplant coordinators, social workers, psychiatrist, nutritionist, financial counselors, and others each with a respective voice in selecting individuals to be acceptable for transplantation and placed on a transplant waiting list.

The selection of medically appropriate candidates has obvious similarities between organ and VCA. Patients must not have major cardiovascular, cerebrovascular, infectious, or malignant contraindications to both major surgery and lifelong IS . The technical considerations of VCA include vascular, neurologic, skeletal, and soft tissue matching that has substantial variation between every patient. The technical approach for each patient is highly unique and planned to an extent not necessary for most solid organ transplant recipients.

Psychosocial criteria center on recipients who must be carefully chosen to minimize the risk of noncompliance causing rejection. Liver transplantation for alcoholic hepatitis in particular adds the risk of graft failure from recidivism. In VCA, changes in self-perception and extensive rehabilitation demands should increase the stringency of the selection process.

The SOT literature has provided extensive analysis of risk factors for medication nonadherence. Histories of substance abuse or pretransplant nonadherence, poor understanding of the transplant and IS , and low perceived self-efficacy [1–3] should raise concern for nonadherence. Beyond medication compliance, VCA (and especially extremity) recipients must participate actively in potentially grueling physical therapy programs. Because of this, VCA recipient selection committees should further evaluate recipient motivation level for rehabilitation .

While all SOT recipients do not generally require psychiatric assessment, VCA recipients require both psychiatric assessment and possible plans for long-term management. VCA is unique in that the mechanism of disease is usually traumatic; significant psychiatric trauma may also manifest in the form of posttraumatic stress disorder. This may require specific attention that will be new to transplant professionals. Furthermore, the principles of SOT do not adequately address the subjective satisfaction of VCA recipients. Function of a solid organ is essentially binary: the graft functions or it does not. “Perfect” graft function in a VCA (total restoration of native form and function) may never be feasible, and grafts fall along a continuum of partial restoration. Because of these difficulties, reconstructive surgeons commonly stress management of patient expectations.

Appreciation of a defect by living for a period of time with deformity can increase satisfaction with reconstruction [4, 5], and is considered by some essential to providing informed consent for VCA. A parallel with regard to timing may be seen in fulminant hepatic failure. Patients may undergo the entire selection and transplantation process while intubated and sedated, unexpectedly emerging with a lifesaving allograft that demands lifetime medication compliance. While these recipients largely have good outcomes even in cases of fulminant alcoholic hepatitis [6], VCA are unlikely to be lifesaving with a few possible exceptions such as chest or abdominal wall. Because of this, an acute stage transplant will likely require higher justification. One face transplant has been described in which multiple failed salvage attempts and a large exposed defect and threatened a patient’s life, leading to urgent transplantation [7]. The outcomes from this case are likely to be scrutinized to determine whether the parallels of emergent liver transplantation truly apply.

The selection of transplant center for VCA will have unique challenges in comparison to SOT. Currently, transplant centers are supervised by specific government regulations and required for public disclosure of patient and graft outcomes on a biannual basis. VCA has not achieved a place as a standardized therapy, and while the government has recently issued guidelines for the oversight of VCA in parallel to SOT [8], most VCA have been performed as parts of institutional review board (IRB)-approved clinical trials. Outcomes from individual centers are not accessible for either patients or referring physicians to make decisions. Just as in SOT, the surgeon must be part of a multidisciplinary team, including transplant physicians, psychiatrists, social workers, immunologists, pathologists, and nurse coordinators. The recipient must be able to count on lifelong follow-up for IS and its potential complications. Finally, the size and technical expertise of the surgical team itself cannot be discounted. Unlike SOT, reconstructive transplants may violate conventional anatomic boundaries and require a team of multiple surgeons working in tandem for over 24 h. The expertise of one or two surgeons will not be sufficient in these cases. It is likely that reconstructive transplantation , even more so than SOT, will remain the province of only select few academic centers with the necessary infrastructure and multidisciplinary resources.

VCA requires an equivalent level of immunological stringency as SOT, with additional constraints imposed by extensive recipient sensitization as well as needs for anatomical compatibility not encountered in SOT.

As with SOT, current immunosuppressive regimens largely allow transplantation to occur regardless of human leukocyte antigen (HLA) type. Although a VCA itself does not demand more stringent crossmatching, certain characteristics of VCA recipients may impose severe constraints on donor selection: VCA recipients are likely to have undergone multiple reconstructive procedures, possibly with allogeneic biological materials and multiple blood product transfusions over time. The virtual crossmatch, as in kidney transplantation, is useful for narrowing the donor pool appropriately in these patients.

The assessment of tissue quality for potential VCA donors includes donor characteristics such as age, and comorbidities, including vascular disease that may shorten the life span of the graft. As opposed to recipient tobacco use, donor tobacco use is not a significant donor factor in SOT and should not be expected to affect VCA outcomes.

In addition to screening techniques translated from SOT, physical parameters must also be accounted for in VCA. Skin color, gender, and basic morphometric parameters such as intercanthal distance, mandibular width, and upper anterior facial height can be easily checked against the potential recipient. Unlike SOT, however, many of these parameters are malleable according to surgeon and recipient preference. Physical selection stringency can be adjusted without affecting immunological outcomes, for example, by considering opposite-gender face donors for a highly sensitized recipient.

Unlike SOT, in which remotely transmitted data can be used to judge organ quality and suitability for a given recipient, to date no VCA has been reported in which the allograft was accepted by the transplant team without the opportunity for physical examination. While purely objective criteria may one day be developed using color matching, cephalometry, and computed tomography, these data currently serve only as adjuncts to the personal examination of a prospective donor.

Surgical teams typically recover solid organs in a tightly choreographed multi-team operation that begins with thoracoabdominal incision and ends 2–3 h later with removal of all visceral organs in immediate sequence [9, 10]. In contrast, the variability of VCA between organ type and recipient defect extent prevents prescription of a standard protocol.

If a donor is a candidate for VCA but not solid organ donation, the sequence is simple. For a multiorgan donor, however, some level of coordination is necessary. Beginning VCA procurement first may threaten solid organ integrity if donor perfusion is impaired by prolonged anesthesia or blood loss. Because they are potentially lifesaving, solid organs must ultimately be given priority. Organs such as extremities, abdominal walls, or smaller face allografts, which can be procured quickly and are unlikely to impact donor physiology, can continue to be procured before the start of thoracoabdominal dissection. VCA such as trachea and uterus, which lie deeper and can be quickly isolated after cardiac death, are more suited to procurement following cold cardioplegia infusion and cardiac explantation, in sequence with abdominal organ procurement . Abdominal vessel cannulation for rapid cooling of VCA is unlikely to interfere significantly with solid organ procurement.

Complex face allografts represent a unique challenge in procurement. Isolation of multiple vessels, nerves, muscles, and osseous structures in situ [11] may require well over 12 h. The ideal approach would begin with face procurement and coordinate teams’ actions so that each procurement could conclude immediately following systemic heparinization of the donor: a “face-first, concurrent completion” approach. It would also incorporate mechanisms for proceeding quickly to procurement of solid organs if their integrity is threatened [12].

Clinical and basic research has provided solid organ transplant surgeons guidelines regarding the amount of time each type of organ can withstand cold ischemia. Extrapolating from free tissue transfer and hand transplantation , ischemia times under 4 h should be well tolerated by VCA [11, 13, 14]. The skeletal muscle component is likely to be less tolerant of cold ischemia than solid organs [15]. Prolonged subcritical ischemia time may furthermore increase risk of rejection [16].

Unlike solid organs, however, VCA do not have an established acceptable cold ischemia time. The greatest difference compared to SOT is an unprecedented level of variability in the graft itself, which may never allow “hard” temporal limits on VCA cold ischemia. Tolerable ischemia time is heavily influenced by type and proportion of tissues. SOT typically are constant in size and tissue content, encapsulated within a fascial layer and attached only by their vascular pedicles and ductal structures. The margins of a VCA, on the other hand, vary following the recipient defect not only in breadth but also in depth and in types of tissue.

Despite this variability, surgeons performing VCA would benefit significantly from guidelines establishing maximum cold ischemia limits for defined categories of tissue types, for example, soft tissue only, musculocutaneous, osteocutaneous, and osteomyocutaneous. Further research may additionally help to identify whether size of the allograft influences speed of initial cooling and therefore tolerance to further ischemia.

Substantial research has been conducted in both solid organs and VCA regarding the optimum means of organ preservation . While various strategies, including modification of preservation solutions and pulsatile perfusion, have been attempted to decrease cold ischemic damage, the standard approach remains simple cold storage in a fluid such as University of Wisconsin solution.

Standardized techniques for organ procurement allow the sharing of organs on regional and national scales. If VCA preservation strategies are optimized, it is conceivable that logistics could allow sharing between different centers. Allograft type and complexity are likely to represent the largest limit to organ sharing. Even an extremity allograft could potentially be procured with generous margins, shipped, and customized to the recipient defect on the back table.

Organ sharing and allocation is a perpetual topic of discussion in SOT, while, VCA may never require this type of scheme. Such strategies in SOT are motivated by the chronic shortage of donors for a large population of patients in need of transplantation. This is illustrated by 2012 UNet data from the US Organ Procurement and Transplantation Network. The median adult waiting time for in the past decade was 4–5 years for a kidney and 4–14 months for a liver. These wait times reflect high transplant volume, and higher demand for organs: In 2012, 34,000 kidney and 11,000 liver recipients were added to waiting lists, compared to 14,000 donors in the same year. In contrast, the yearly volume of potential VCA recipients is unlikely to exceed 0.1–1 % of these figures in the near future.

To this date, the longest reported waiting period for a VCA has been 8 months, not due to competition for the same graft but rather by factors, including recipient sensitization, strict anatomical criteria, limited geographical search area, and low public awareness leading to reticence to approaching every potential donor family about VCA donation. Allocation of VCA in the future will likely be limited by these factors as well as small overall pools of both donors and recipients. Initial work will need to focus on increasing the donor pool by boosting public awareness of VCA donation and transitioning to a standard-of-care approach. Subsequent efforts should attempt to establish a system for defining objective VCA allograft requirements for a given recipient, maximizing the donor pool by expanding geographic range. Allocation schemes that determine priority based on severity of disease (such as Model for End-Stage Liver Disease (MELD) for liver) or time on waiting list (as in kidney transplantation) are less likely to be relevant or necessary.

The 2013 decision to regulate VCA as organs under the auspices of the Health Resources and Service Administration, Department of Health and Human Services [8

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