The Persistent Vegetative State: The Medical Reality (Getting the Facts Straight)

The Persistent Vegetative State: The Medical Reality (Getting the Facts Straight) The first step in any bioethical dilemma is to collect the facts and to understand the medical reality of the situation. Nowhere is this more necessary than in treatment decisions concerning patients with serious neurologic impairments. Modern medicine's half-way technologies have produced new neurologic creatures and required new terminology to describe syndromes both more complex and more common than anticipated a few decades ago. Unfortunately, enormous conceptual and scientific confusion persists concerning the characteristics of these new syndromes, which include brain death (whole brain death), persistent vegetative state (PVS), permanent unconsciousness, coma, dementia, irreversible coma, chronic and irreversible coma, neocortical death, and locked-in syndrome. For example, many over the last ten years mistakenly believed that Karen Quinlan was brain dead. Others, including neurological specialists, continue to consider the persistent vegetative state a form of coma. Many, including physicians, still believe that permanently unconscious patients, such as those in a persistent vegetative state, can experience pain and suffering. In addition, there is little consensus about the appropriate terminology to describe such syndromes. In its 1986 statement on fluids and nutrition, the American Medical Association's Council on Ethical and Judicial Affairs used the misleading term "irreversible coma." British physicians continue to apply broadly the phrase "brain stem death," a medical syndrome that simply does not exist except in extremely rare situations. Many physicians, especially in Europe, use imprecise and antiquated language such as "coma vigile," "akinetic mutism," and "apallic state" to describe some syndromes. The term "chronically and irreversibly comatose" as used in the Child Abuse Amendments of 1984 will be an endless source of confusion. If the medical profession persists in failing to understand these syndromes and continues using inconsistent and incorrect terminology, how can the rest of society begin to unravel the complexities of neurology and lay the foundation for a moral and legal analysis of the issues emanating from these neurologic conditions? A full understanding of the medical facts about persistent vegetative state, including an examination of the significant similarities and differences between it and several other syndromes, is essential before we can begin to apply appropriate moral and legal principles to individual cases and to develop meaningful social policies. The Medical Reality It is first important to differentiate brain death (whole brain death) from the persistent vegetative state. [1] The brain stem, the lower center of the brain, basically controls vegetative functions, such as respiration, and primitive stereotyped reflexes, such as the pupillary response to light. Additionally, it contains the activating or arousal system for the entire brain called the ascending reticular activating system. The cerebral hemispheres, in turn, contain the function of consciousness or awareness (which is more precisely located in the outer layers of the cerebral hemispheres, the cerebral cortex), as well as other important voluntary and involuntary actions, such as control of movements. When brain death occurs, these higher cerebral functions cease; in addition, all brain stem functions are lost--eye movements, pupillary response to light, the most primitive protective reflexes such as the cough, gag, and swallowing, and spontaneous respiration. Heart beat, as well as other vegetative functions related to internal homeostasis, can continue, since these functions are semi-autonomous, i.e., they are not completely dependent on the integrity of the brain stem. By contrast, in cases of patients in a persistent vegetative state, the brain stem, including the ascending reticular activating system, is relatively intact. …