by Arthur Caplan, Ph.D.
Researchers at Yale University recently reported an experiment in which they used an experimental chemical solution to create electrical activity in the cells of pig brains, brains obtained from a slaughterhouse four hours after the death of the animals from decapitation (NY Times ‘Partly Alive’: Scientists Revive Cells in Brains From Dead Pigs, 4/17,19). These results led to all manner of comments in this story, many from bioethicists and in stories elsewhere. Commentators suggested that the pigs’ brains were somehow made partly alive, that concerns about consciousness recurring in the dead now needed to be addressed and that the experiment called into question the current understanding of brain death used to pronounce huge numbers of persons dead all over the world.
The experiment did not justify any of these conclusions. Worse, comments about partial life may frighten people into thinking their loved ones were declared dead when they were not or that they and their loved ones should not agree to serve as organ or tissue donors due to new doubts over the validity of brain death.
Many persons around the world are pronounced dead due to cessation of cardiac function. Yet it is possible to induce contraction in an isolated heart taken from a dead animal. The Langendorff heart, or isolated perfused heart assay, is a common in vitro technique that has been used for 90 years in pharmacological and physiological research using many species of animals. It allows the examination of cardiac contractile strength, cardiac disease and heart rate without the complications of an intact animal. That a heart and heart cells can be induced to beat for hours post-mortem is interesting even amazing but that experiment does not call into question the pronouncement of death using the cessation of cardiac function or the need to declare that partial life has been induced.
Restoring some form of disorganized, non-functional electrical activity in the cells of a long dead brain does not cast doubt on the notion of brain death which requires the total, irreversible loss of brain function. Nor is there any such state as ‘partially alive’. Corpses in which skin lives on and digestion occurs in the grave are not partially alive. They are, like the brain cells from the Yale pigs, activities in dead bodies.
The Yale study should not be a source of wild, irresponsible speculation about reanimating the dead, creating new states of partial life or tossing out brain death definitions. Pronouncing death and organ donation are too important to permit a demonstration that cells can be stimulated to fire up in some way drawn from a most certainly deceased pig to declare that a conceptual revolution has just occurred.