**3.2 Thoracoabdominal normothermic regional perfusion**

While the circuit for abdominal NRP may be established pre-mortem, cannulation to establish a complete thoracoabdominal NRP circuit is done post-mortem in the operating room. After the declaration of death, the chest is entered through a midline sternotomy, and the pericardium is opened. A bolus of heparin is injected into the heart directly, an arterial cannula is inserted into the distal ascending aorta/aortic arch, and a venous cannula is inserted into the right atrium. Cannulae are connected to the tubing of the primed NRP circuit, the aortic arch vessels are clamped, and NRP is initiated.

#### **Figure 2.**

*Abdominal normothermic regional perfusion. Cannulae are placed in the femoral artery and vein in the groin region. A Fogarty balloon catheter is introduced through the contralateral femoral artery and positioned in the supraceliac abdominal or thoracic aorta.*

During thoracoabdominal NRP, pump flow is maintained ≥2.5 L/min/m<sup>2</sup> , temperature 35°C, and hemoglobin >10 g/dL. Prompt laparotomy is performed to assess hepatic and intestinal perfusion and to exclude the lower extremities from the perfusion circuit. Once cardiac contractility has been restored, weaning from NRP is attempted. If the heart is able to take over circulation, functional assessment is performed using transesophageal echocardiography and pulmonary artery flotation catheter (Swan-Ganz) monitoring. In general, acceptance criteria for a cDCD heart recovered with NRP include central venous pressure ≤12 mmHg, pulmonary capillary wedge pressure ≤12 mmHg, cardiac index ≥2.5 L/min/m<sup>2</sup> , and left ventricular ejection fraction ≥50% [15–17].

## **4. Clinical outcomes using normothermic regional perfusion in donation after circulatory death**

To date, the great majority of human transplants performed using organs recovered with NRP have been donor using DCD kidneys and livers. In more recent years, the use of DCD pancreata and even hearts recovered with NRP has also been reported.

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*Normothermic Regional Perfusion in Solid Organ Transplantation*

of DGF in the immediate post-transplant period was not [27].

70% of patients with ITBL require re-transplantation or die [32].

The cells of the liver, in particular those lining the biliary tree, are particularly sensitive to warm ischemia, and initial experiences with DCD liver transplantation described high rates of graft dysfunction and non-function and non-anastomotic biliary strictures/ischemic type biliary lesions (ITBL) in up to 50% of cases [29]. While complication rates have improved with experience, the rate of post-transplant ITBL remains higher among recipients of DCD versus DBD grafts: 16 versus 3%, according to two meta-analyses [30, 31]. The clinical relevance of ITBL lies in the fact that up to

After an initial period where different donor maintenance techniques were used, including rapid *in situ* cold preservation, simultaneous chest and abdominal compressions, and TBC, NRP has come to be the "gold standard" and primary means by which uDCD livers are recovered for transplantation. Using NRP, even livers with extensive pre-recovery warm ischemic periods of up to 2.5 hours have been successfully transplanted, with biliary complication and graft survival rates comparable to those seen using cDCD livers that have suffer considerably less warm ischemia [10, 11, 33–35]. In spite of its relative success in the setting of uDCD, the application of NRP in cDCD liver transplantation remains more limited. The great majority of cDCD livers that are transplanted in the world today are still recovered with rapid *in situ* cold preservation, and reports on the use of NRP in cDCD liver transplantation have been, until recently, anecdotal [12, 24–26, 36, 37]. In the past year, however, two larger multicenter studies have come out describing the benefits that may be achieved with post-mortem NRP in cDCD liver transplantation. First, a Spanish national study compared the results of 95 cDCD liver transplants performed with post-mortem NRP with those of 117 cDCD liver transplants performed with super rapid recovery (SRR). Median donor age in the study was relatively high (57 years [25-75% interquartile range, IQR 45–65] NRP, 56 years [25-75% IQR, 47–64] SRR). With a median

When compared with other solid organs for transplantation, the kidney is relatively resilient and withstands the ischemic insult inherent to the DCD process relatively well. Nonetheless, kidneys from DCD donors recovered with NRP as opposed to rapid *in situ* cold preservation or hypothermic perfusion/"total body cooling" (TBC) have demonstrated significantly better immediate as well as ongoing graft function [18–20]. Reports from different groups in Europe, the United States, and Asia have described the use of NRP in both uDCD and cDCD kidney transplantation, with rates of delayed graft function (DGF) around 50–70% and 30–40%, respectively; negligible (if any) primary non-function (PNF); and excellent 1-, 5-, and even 10-year graft survival rates [19–27]. While reported rates of DGF may still seem to be high even among DCD kidneys recovered with NRP (especially those arising through uDCD), the pathogenesis and, consequentially, implications of DGF seem to be less severe than those associated with DGF arising in the context of DBD kidney transplantation. Ischemic injury appears to be implicated to a greater extent in the development of DGF among DCD kidneys, whereas, in DBD, alloimmune phenomena prevail [28]. A recent large single-center study reported 73% DGF among 237 uDCD kidneys recovered with NRP versus 46% among a contemporary cohort of matched DBD kidneys, but 10-year graft survival rates did not vary at all between the two groups and were excellent in both (82 and 80%, respectively). The authors also noted that while donor age >50 years was significantly associated with graft loss among uDCD kidneys, the development

*DOI: http://dx.doi.org/10.5772/intechopen.84771*

**4.1 Kidney transplantation**

**4.2 Liver transplantation**
