Dear Mr. Premack: I am very angry with my mother’s physician. Two years ago when mother was in great health she went to her own attorney to discuss her medical directives. Her attorney drew up binding legal documents according to the law, and mother reviewed them, approved them and signed them in front of witnesses. In the last year, mother’s health has gone bad. Last week her doctor told her that she has Alzheimer’s and asked her what she wants in the way of artificial life support as her condition progresses. Mom’s answer, considering her confused condition, was "I don’t know." When I said she had signed a Directive to Physicians, he said he felt her statement cast doubts on its validity. Why in the world would the doctor, who just diagnosed her with Alzheimer’s, ask her that question? Has the doctor messed up the legal plan that mom agreed to and signed two years ago while she knew what she was doing? – GB

Way back in 1977 the Texas legislature passed a law allowing adults to make their own decisions about their future medical care in advance of need. That law was modernized in year 2000. It allows adults to decide whether they want life support, and allows appointment of an agent to make various medical decisions as a surrogate.

In her Directive, your mother would have stated she did not want life support if she was diagnosed with a terminal or irreversible condition, or if she had a crisis and her death was imminent. She made those choices while she was thinking clearly and was in good health so that they would apply later on if she became too ill to think clearly about those issues.

Texas law states clearly that a Directive to Physicians may be revoked at any time without regard to the declarant's mental state or competency. Even a verbal statement showing a change of mind can revoke it. If the revocation is verbal, the doctor must record in the patient's medical record the time, date, and place of the revocation and to mark each page of the Directive with the word "void".

Ultimately, the point of having an advance directive is to allow the patient’s wishes to be followed. The doctor, when he is told of the Directive, must certify the diagnosis of the patient as either terminal or irreversible before the Directive can be given effect. The doctor must also determine that any proposed steps (like withholding life support) are in accord with the patient’s desires. That is why he asked.

As a consequence, it can actually be quite easy for a patient to verbally contradict the wording of the written Directive. Even a confused expression of doubt, like your mother’s, may cause her doctor to conclude denying life support to her may no longer be in accord with her desires. Her response may interfere with enforcing the Directive she signed two years ago.

What can you do when the patient has questionable judgment? The answer lies with the other type of advance medical directive: the Medical Power of Attorney. The "regular form" should be modified to say that it is intended for the Directive to Physicians to be enforced. It should also be changed to say that if the Directive is for any reason void, then the Agent may, as surrogate decision maker, instruct the doctor to withhold or disconnect artificial life support. The Agent takes over if the doctor certifies the patient lacks the ability to understand the nature and consequences of a treatment decision. Whether there is a valid Directive or not, with these modifications the Agent can instruct the physician that life support is no longer a desirable option.

With the backup that can be provided in a properly modified Medical Power of Attorney, people in your mother’s situation can avoid uncertain legal-medical status that may arise from a voidable Directive.