Excerpted from the Revised (1999) Edition of "Nutrition and Hydration: Moral Considerations: A Statement of the Catholic Bishops of Pennsylvania." Click here for the full text.

Recent court decisions and the enactment of federal and state laws governing advance medical directives (living will or durable power of attorney) have given many the impression that anything the courts or the civil laws allow is morally acceptable. The issue of the withholding or withdrawal of nutrition and hydration in particular has become controverted. ...... Modern medicine continues to deal with age-old questions, even though current knowledge and technologies offer treatments and procedures that would once have been impossible. One such area is the supplying of nutrition and hydration to patients who are incapable of feeding themselves and are unable to take nourishment orally even with assistance. It is now possible to sustain the lives of such patients with a variety of techniques, and so arises the question of the moral obligation to do so. ...... All states of unconsciousness are often referred to (even by medical personnel) as "coma." This is, in fact, not a correct designation.(10) Coma is but one type of impaired consciousness. There are also others which we should consider because all of them present situations in which problems may arise in terms of the supplying of nutrition and hydration.
A true coma is a state of "unarousable unresponsiveness" with no response to external stimuli. The person is not dead, but is in a state of sleep. This condition is never permanent.(11) It may last as long as six months, but it will resolve itself into some other state. The person may emerge into consciousness again or sink into another state, such as that which is referred to as the persistent vegetative state. It may take some time, even months, to diagnose the exact condition. The persistent vegetative state (PVS) is deeper than a coma. The coma is a state of sleep; PVS is a form of deep unconsciousness. The cerebrum, the upper part of the brain, gives evidence of impaired or failed operation - and it is this portion of the brain, in its cortex or outer layer, which is responsible for those activities that we recognize as specifically human.(12) Another portion of the brain, the brainstem, is, however, still functioning in the PVS patient. It is this portion of the brain which controls involuntary functions such as breathing, blinking, involuntary contractions, and cycles of waking and sleep. Thus PVS patients may open their eyes and sometimes follow movement with them or respond to loud and sudden noises (although these responses will be neither long sustained nor apparently purposeful). There will be cyclical stages of sleeping and waking, but such activity is a function of the brainstem and is not an indicator of purposeful human activity."(13) PVS is sometimes referred to as "cerebral death.
" This is an unfortunate terminology, since it seems to imply that there is "brain death" as described earlier. This is not true. There is a failure of function at one level in the brain, but not all, and the person in PVS is definitely not dead. Even medical personnel sometimes refer to such a patient as "brain dead." This is simply not the case.(14) There is also a state which is referred to as psychiatric pseudocoma. This is a state of unconsciousness caused by shock or trauma which lead the victim to close off from the outside world. This may be so severe as to give the appearance of death, but it is not even truly a state of unconsciousness. It is simply total lack of response. Finally, there is another condition which is referred to as the locked-in state. This condition is caused by an interruption in the descending motor pathways of the nervous system. In this condition, paralysis, not cognitive failure, leads to a lack of ability to communicate."(15) The patient is fully conscious, but simply has no way in which to indicate conscious response. (In some cases, however, depending on where the motor pathways are interrupted, communication may be possible by such means as coded eye blinking.) It takes careful diagnosis not to mistake this patient for the PVS patient. PET scans can distinguish between the locked-in state and the persistent vegetative state. The EEG, however, cannot do so, since the patient in the locked-in state may show an abnormal response, while the PVS patient may produce readings that are near-normal.
(16) Patients who have recovered from this condition reveal that they were indeed conscious and well aware of what was going on around them - and had a strong desire to continue to live. In none of these classes of unconscious patients are we dealing with the dead. All of them are alive and some of them may well be expected to recover. The one case in which recovery becomes most unlikely is that of the PVS patient, and it is this patient who is likely to become the object of decision making in regard to continued treatment or care, or supplying of nourishment. ORDINARY AND EXTRAORDINARY MEANS OF CARE(17)The Catholic moral tradition holds that one is morally obliged to use the ordinary means of sustaining life, but is not obliged to make use of extraordinary means."(18) Ordinary means are those which are available and do not require effort, suffering or expense beyond that which most people would consider appropriate in a serious situation. This would include most of the developed procedures and techniques commonly practiced in medicine and surgery. However, moralists recognize that there are also subjective elements which influence our ability to make moral judgments. Subjective considerations of pain, expense and personal abhorrence may act as obstacles to the fulfillment of this obligation. Furthermore, not all techniques have to be used in every instance. What would usually be ordinary means may, in certain cases, offer little hope of success and may prove more burdensome than beneficial to the user.
In such situations one would not be morally obliged to use such means.(19) The distinction between ordinary means (which we are morally obliged to use) and extraordinary means (which we may choose to use, but are not obliged to) is not based solely on the commonness and availability of the means themselves, although this is taken into account. It is also based on the results that one can expect and on certain serious subjective considerations and attitudes as well. It takes into account the proportion between benefit and burden. ...Feeding Methods