Figure 2.

Proposed refinements to normothermic regional perfusion (NRP) techniques. A, Abdominal NRP. The procedure has been used in 12 donors with occlusion of the descending thoracic aorta and a large cannula in the ascending aorta. Delivery of oxygenated blood into the aorta rather than the iliac vessels excludes the possible collateral circulation between the inferior epigastric and internal thoracic arteries (collateral circulation B in Figure 1A). B, Direct (hypothermic) procurement and perfusion (DPP) with abdominal‐normothermic regional perfusion (A‐NRP). During the dissection, Stage 1, the descending thoracic aorta is occluded, a double lumen cannula inserted into the ascending aorta and left open to atmosphere, and A‐NRP commenced. In Stage 2 cardioplegia is administered rapidly before explantation of the heart by temporarily placing a clamp on the ascending aorta cephalad to double lumen cannula. After explantation of the heart, Stage 3, the ascending aortic clamp is repositioned proximal to the double lumen cannula to open the aortic arch vessels to atmosphere for the duration of A‐NRP. C, Thoraco‐abdominal NRP. The cephalad ends of each of the aortic arch vessels are cannulated and any drained blood returned to the venous reservoir for retransfusion