Author(s): Lauren Alderette, James Taylor Lloyd

1. The first successful human organ transplant (kidney) was performed in 1954. Since that time, the heart, lungs, liver, pancreas, intestine, stomach, testis, penis, hand, thymus, and uterus have all been successfully transplanted. It is not uncommon today to have a patient undergo a transplant of two organs in the same surgery (eg, heart–liver, heart–kidney, pancreas–kidney, etc.).

2. From the mid-1950s to the early 1970s, individual hospitals and organ procurement organizations independently managed most aspects of organ donation and transplantation. In 1984, the United Network for Organ Sharing (UNOS) was established to coordinate the allocation of organs and systematically collect data regarding donors, transplant candidates, and recipients across the United States. Since then, UNOS has played a central role in overseeing the national organ procurement and transplantation network. Recently, however, legislative and regulatory efforts have emerged aimed at diversifying, modernizing, and potentially restructuring the framework governing organ procurement and transplantation in the United States.

3. Although demand continues to exceed supply, modifications of the organ allocation system, expansion of criteria for acceptable donor organs, and advances in organ preservation techniques have increased the availability of organs and improved allograft survival.

   1. The LifePort Kidney Transporter is a perfusion preservation machine for donor kidneys that works by pumping the renal vasculature continuously with a cold perfusate, reducing the odds of delay in kidney function and improving first-year posttransplant success compared with static storage.

   2. US Food and Drug Administration–approved transport systems have been developed for donor lungs (eg, TransMedics’ OCS Lung, a “lung-in-a-box” device). This machine maintains normothermia, breathing, and perfusion throughout transport, allowing expanded retrieval ranges and successful use of organs that had been rejected by transplant centers using cold storage.

   3. Similar devices are now under investigation for donor hearts and livers. Recently, there have been significant advancements in organ preservation and procurement technologies designed to enhance transplant outcomes and expand the donor organ pool. Two prominent normothermic machine perfusion platforms—the OrganOx metra device and the TransMedics Organ Care System (OCS)—are increasingly utilized in clinical practice. These devices maintain donor organs, such as livers, at physiologic temperatures while providing oxygenation, nutrients, and the ability to monitor organ function prior to transplantation. This approach contrasts with traditional static cold storage, potentially allowing for prolonged preservation, improved organ assessment, and

      utilization of marginal organs. In addition, normothermic regional perfusion (NRP) is an emerging technique in which circulation is re-established in the donor following circulatory death, enabling organs to be assessed and recovered under physiologically optimal conditions. Similar perfusion devices and methods are currently under investigation for heart transplantation, reflecting an evolving landscape toward broader use of normothermic perfusion technologies to improve transplant outcomes and expand access to transplantation.

4. The success of solid organ transplantation critically depends on the careful selection of transplant recipients. The suitability of candidates is typically determined by a multidisciplinary committee and based on national criteria.

   1. Patients require a thorough history and physical examination as well as psychosocial evaluation to identify any behavioral, social, or financial issues that may preclude adherence to immunosuppressive therapy and medical follow-up after transplantation.

   2. In addition to standard laboratory tests, serologic tests for varicella, measles, mumps, rubella, HIV, hepatitis, tuberculosis, syphilis, cytomegalovirus, Ebstein–Barr virus; drug screening; ABO-Rh blood typing; age-appropriate screening; and electrocardiography (ECG) are required.

   3. Lifesaving transplants, defined by liver, lungs, heart) are per the decision of the primary team and OR team.

   4. The need for additional cardiac and pulmonary testing is dependent on patient comorbidities as well as the type of transplant to be performed.

   5. Absolute contraindications include active infection, active malignancy, substance abuse not in stable remission, uncontrolled psychiatric disease, life expectancy less than 1 year, and ongoing nonadherence to medical or psychiatric treatment.

   6. Ethical issues in transplantation are numerous and include how death and brain death are defined, financial incentives, organ trafficking, and coerced donation. A full discussion is beyond the scope of this chapter.