Showing posts with label pvs. Show all posts
Showing posts with label pvs. Show all posts

Monday, October 19, 2009

When Does Life Begin and End? -- the Debate Continues

Frederick Grinnell of Oxford University press in his blog post, Redefining Death — Again responds to the recent Nature editorial, “Delimiting death.” Grinnell’s post contributes to the ongoing public policy debate regarding the relationship between biological and spiritual life.

In addition to this post, there are several other articles that are of significance: Dr. James Bernat, neurologist at Dartmouth, wrote an article entitled Chronic Consciousness Disorders, Annu. Rev. Med. 2009. 60:381–92. The article notes that new functional neuroimaging techniques using PET and fMRI provide a new and complementary way to assess consciousness; that fMRI technologies are showing that 'persistent vegetative state' is not always clear cut -- that there is more of a continuum and that some 'PVS' patients are in fact closer to 'minimally conscious.' The author cites recent provocative studies suggesting that fMRI in unresponsive patients may detect evidence of conscious awareness when a careful neurological examination cannot.

Second, while doing research for my chapter on regenerative Nanomedicine, I came across this very interesting article, available at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2672310/ , entitled Shorting Neurons with Nanotubes by Gabriel Silva, a professor of bioengineering at UC San Diego. The abstract explains that new insights are emerging about the interactions between brain cells and carbon nanotubes, which could eventually lead to the development of nanoengineered neural devices, i.e., possible neural prostheses.

Finally, there are excerpts on CNN of Dr. Sanjay Gupta’s Cheating Death, available at http://www.cnn.com/2009/HEALTH/10/12/cheating.death.excerpt/index.html, which explores novel applications of therapeutic hypothermia to prevent injury to the brain, along with other stories of life-saving medical discoveries.

These articles and recent findings all have profound implications for end-of-life decisionmaking. While recently, an editorial in Nature magazine called for expansion of the definition of death in order to increase organ donation (http://www.nature.com/nature/journal/v461/n7264/full/461570a.html ), it seems that between the new diagnostics, the potential for neuro-prosthetics, and what we are finding out about 'cheating death’, that we should not necessarily be expanding the definition of death, but realizing that we that are expanding the boundaries of life. In doing so, we need to consider the implications for an aging population, as well as the societal and environmental impacts.






Thursday, January 24, 2008

Treating the Dead and Redefining Death

From Newsweek, an article about the science of resuscitation and how our understanding of death is changing. The particular quote that captured my attention: "But if the cells are still alive, why can't doctors revive someone who has been dead for an hour? Because once the cells have been without oxygen for more than five minutes, they die when their oxygen supply is resumed."
If we can figure out how to do gradual and safe reperfusion of the cells, will this change the definition of death? This would be a incredible advance, similar to when CPR became standard practice.

In a similar vein, the International Network for the Definition of Death, an affiliate of the International Association of Bioethics, is having its 5th International Symposium, and is devoted to the discussion of the ethical and medical issues associated with:
bulletdiagnosis and differentiation of brain death, coma, and persistent vegetative state
bulletdifferentiation of anencephaly and other severe neurological deficits from brain death
bulletorgan transplantation and termination of treatment decisions for the brain-dead and neurologically impaired
bulletphilosophical issues of personhood and rights related to the status of the brain dead and neurologically impaired.


For more information on this, click here.