To the Editor,

Rubin argues that the use of normothermic regional perfusion (NRP) during organ recovery in donation after the circulatory determination of death (DCD) amounts to euthanasia of the donor (1). We disagree.

The determination of death of the donor is made using well accepted standard medical criteria, used in everyday clinical practice as well as in DCD organ recovery when NRP is not used. The American College of Physicians and others (who raise questions regarding the ethics of NRP) accept these criteria for death determination in DCD when NRP is not used (2). If this determination of death is accepted, then any procedure carried out before NRP cannot be considered as euthanasia, which is not possible in someone who is already dead.

The dead DCD donor must first be resuscitated back to life before any subsequent intervention can logically be considered as the cause of death. This includes clamping of the arch vessels or the descending thoracic aorta, which does not induce brain death in someone already confirmed dead using circulatory criteria. It allows the creation of a regional rather than a general circulation and provides reassurance that there is no possibility of restoration of brain function. All procedures to ensure that the NRP circulation is regional and not systemic are undertaken after death determination and before starting the regional normothermic circulation (3).

Euthanasia is therefore only possible if NRP itself can first restore life. In abdominal NRP these procedures aim to exclude blood flow to the limbs, thorax, head, neck, and brain. In thoraco-abdominal NRP, flow to the limbs, head, neck, and brain are excluded. The regional circulation created by NRP can only be interpreted as reperfusing and repairing organs intended for transplantation and not as a procedure that restores life itself.

While the legal, biological, philosophical, and cultural definitions of death may differ, the medical criteria used for its determination are increasingly uniform (4-6). The loss of brain function, particularly the capacity for consciousness and for breathing spontaneously, is crucial to the determination of death, whether neurological or circulatory criteria are used for its determination (7). Resumption of brain function is impossible when brain blood flow is absent and cannot be restored with NRP. Current evidence suggests that brain blood flow is not restored during either type of NRP (8,9). It should also be clear that the brain would have been exposed to a median of 16 minutes of no-flow anoxia preceded by a varying time of low-flow warm ischemia before thoracoabdominal NRP is initiated. Nevertheless, we acknowledge that further studies definitively demonstrating that brain blood flow is not restored by NRP are required before its more widespread implementation (10).

NRP respects an individual’s decision to have their donated organs recovered (not “extracted”) in as good a condition as possible after their death. It also respects the decision reached with the individual or their family not to be resuscitated after death. NRP resuscitates organs for transplantation and does not restore life.

NRP is anything but euthanasia.