Last month, 400 people from 46 countries met in Rome, Italy to focus on one of the quintessential bioethics problems of our day - the patient in the Persistent Vegetative State (PVS). The unfortunate term PVS was coined 1972, when neurologists Bryan Jennett and Fred Plum declared that they had identified a clinical entity distinguished by "wakefulness without awareness" in which a patient, due to head trauma, anoxic event or degenerative disease has lost all cortical (upper brain) functions.1 Few human diseases or disabilities generate more confusion and dread than does the condition of the PVS. Health professionals who care for patients in PVS have called this "the ultimate curse".2
In the years since 1972, the term "Persistent Vegetative State" has come to be applied generically and often inappropriately to patients who actually do show some signs of awareness. It could reasonably be said that the term itself, taken in the commonly understood sense of the term "vegetable", is dehumanizing as well as biologically nonsensical. A human can no more "become" a vegetable than a vegetable can "become" a human being.
The PVS is not easily diagnosed, and as a result, the rate of misdiagnosis appears to be very high, in some studies, approximately 40 percent.4,5 Physical disabilities experienced by many of these patients can prevent them from engaging in behaviors which could make their awareness known to us.ÊWe know this from a number of studies of persons who have emerged from the PVS or who were misdiagnosed in the first place.6,7
Thus the need for the Rome conference, "Life Sustaining Treatments and Vegetative State: Scientific Advances and Ethical Dilemmas", which was sponsored by the International Federation of Catholic Medical Associations, and featured neurologists, bioethicists, therapists and others involved in the care of patients with severe brain injury. The conference highlighted a number of mistaken assumptions and misunderstandings regarding the PVS. As it turns out, the 1972 definition and other more recent attempts at description are not quite nuanced enough to describe the true state of many patients who have suffered severe brain injury.8 Medically, we can measure such things as behavior and movement, but not "thought" or "awareness". One invited speaker, D. Alan Shewmon MD, Professor and Chief of Pediatric Neurology, Olive View-UCLA Medical Center, has noted that the PVS literature suffers from an oversimplified notion of "consciousness" and from conflating consciousness with responsiveness. Furthermore, consciousness is a continuum, not an all-or nothing phenomenon. In general terms, human brains aren't light bulbs with an "on" and "off" switch, but instead are more like irons, with "warm" settings all the way up to "hot".
Many suggestions were offered by conference participants for improving the care of these patients, including the development of more specialized coma care units, nationwide registries for severe brain injury as well as standardized diagnostic and assessment procedures among centers.9 A good deal of the most advanced work in this field is taking place outside the U.S., where low rates of insurance reimbursement for intensive, long-term rehabilitation discourages the development of specialized centers for the treatment of severely brain-injured patients.
Pope John Paul II chose the final day of the conference to issue a statement in which he outlined the care we owe these patients, including nutrition and hydration, and called for improved medical care and rehabilitation for patients with brain injury as well as less-dehumanizing diagnostic terminology. People of all faiths -- and certainly the medical profession -- can embrace the Pope's statement as a patient centered, rehabilitation-oriented document. The Pope's full statement, as well as proceedings of the conference, can be accessed at http://www.vegetativestate.org
1 Jennett B and Plum F. Persistent vegetative state after brain damage: A syndrome in search of a name. Lancet. 1972, 1; 7753:734-737. [Back]
2 Crisci C. The Ultimate Curse. Journal of Medical Ethics 1995; 21:277. [Back]
3 The permanent vegetative state. Review by a working group convened by the Royal College of Physicians, J Royal Coll Physicians London, March/April, 30; 2, 1996. [Back]
4 Andrews K, Murphy, L, Munday R, Littlewood C. Misdiagnosis of the vegetative state: Retrospective study in a rehabilitation unit". British Medical Journal, 1996; 313:13-16. [Back]
5 Childs, Mercer and Childs. Accuracy of diagnosis of persistent vegetative state. Neurology, 1993, 43, 1465-1467. [Back]
6 McMillan TM. Neuropsychological assessment after extremely severe head injury in a case of life or death. Brain Injury. 1996, 11; 7:483-490. [Back]
7 Wilson B, Gracey F, Bainbridge K. Cognitive recovery from Ôpersistent vegetative state': psychological and personal perspectives. Brain Injury. 2001, 15; 12:1083-1092. [Back]
8 The Multi-Society Task Force on PVS. Medical aspects of the persistent vegetative state. NEJM. 1994, 330: 1499-1508. [Back]
9 Gill-Thwaites H. The Sensory Modality Assessment Rehabilitation Technique (SMART) - A tool for assessment and treatment of patients with severe brain injury in a vegetative state. Brain Injury. 1997, 11; 10:723-734. [Back]