Kidney Function

The University of New Mexico’s Center for Health Law and Ethics developed a series of questions (which the developers call a “values history“) for public guardians to sue to ask friends of solitary, incapacitated patients what this person believed or had said about their beliefs, values, health and treatment preferences in order to guide the guardian to make appropriate decisions for an incompetent individual patient who had no other surrogate. As the values history was being developed, it became clear it could be helpful to anyone, not just the person designated as the guardian, to obtain insight into or to clarify their own values, to articulate them, and preferably to record them for use by a surrogate should they become decisionally incapacitated.

Questions in the values history ask about your living environment; your family and friends; your religious background and beliefs; your attitudes toward life in general and toward independence and control, health, doctors, illness, death and dying, and finances. They ask whether you have wishes regarding specific medical procedures, such as dialysis, artificial ventilation, artificial nutrition and hydration and organ donation, and regarding a funeral, eulogy, and obituary. The questions also ask if you have any written documents, particularly advance directives.

Can I be required to have an advance directive?
According to the Patient Self-Determination Act, a federal law, you cannot be required to have an advance directive. This law specifically prohibits health care facilities or providers from conditioning admission or provision of insurance or services upon whether or not you have executed an advance directive.

Why do so few people elect to have advance directives?
Many individuals do not know what an advance directive is, or if they know, do not realize it would be appropriate for them to have. Many others do not have an advance directive because the subject raises unpleasant or frightening issues.

Why should a dialysis patient have an advance directive?
For the same reasons that everyone should have one-and for additional reasons. Dialysis is very effective in prolonging lives of those who would otherwise die of kidney failure. Fortunately, the quality of health and life for the great majority of people on dialysis acceptable and for many substantially better than that. Most people are able to work and can do most of the activities that they wish to do, but as many as 10% of chronic dialysis patients discontinue dialysis because the burdens of illness and treatment outweigh the benefits of continuing to live. Perhaps half of those who discontinue dialysis are no longer able to make decisions for themselves and the time dialysis is discontinued because of inter-current illness with altered consciousness or because of dementia.

By having an advance directive, they are assured of having their own preferences for health care respected, including the continuation of dialysis or of other life-sustaining treatment if that is their preference (or discontinuation, if that is their preference). Furthermore, it is a great relief to family members and to physicians to know a patient’s preferences and to feel secure that they are doing what this person would have wanted them to do.

Monitors are devices that measure several dialysis functions during treatment. Their purpose is to provide safe dialysis treatment and to respond with a light and a noise to alert the staff when something is wrong. When a monitor indicates an alarm, dialysis may be automatically stopped. In most cases, the problem is not immediately dangerous to you and can be quickly corrected by the staff. The combination of the monitors and the supervision of the staff helps to make dialysis treatment as safe and comfortable as possible.

The venous pressure monitor and the arterial pressure monitor measure the pressure of the blood as it flows through the dialyzer. If there is a break, kink, or any type of obstruction in the blood lines or in the dialyzer, the pressure changes and the monitors send out an alarm to alert you and the staff.

The temperature monitor indicates an alarm if the dialysate solution becomes too hot or too cold. Because the blood normally cools when it leaves the body through the blood lines, it must be rewarmed to the normal body temperature before it is returned to the body. This is accomplished by heating the dialysate solution, which, in turn, rewarms the blood.

The negative pressure monitor shows the amount of suction or negative pressure used to remove the excess fluid from the body. An alarm sounds if this pressure changes.

Another very important device on the artificial kidney machine is the blood leak monitor, which sets off an alarm if any blood leaks in the dialysate solution through a tear in the dialyzer membrane.

The conductivity monitor indicates the concentration of substances in the dialysate solution.

The air detector detects any air or foam that might pass through the system. This detector not only indicates an alarm, but also features an automatic device that clamps the blood line returning to the body to prevent air from being pushed into the vein. It may be frightening when an alarm sounds, but the monitors are designed to protect you and to make your treatment as safe and as comfortable as possible.

Commentary on ACCORD Study Group. Effects of intensive blood-pressure control in type 2 diabetes mellitus. N Engl J Med. 2010;362(17):1575-1585.