Chapter 21. Evaluation of the Geriatric Patient

1. The elderly are the fastest growing segment of the population.

2. A healthy elderly patient may have normal organ function but less reserve.

3. There are normal organ and overall functional changes of aging that do not imply disease but must be considered when planning an anesthetic.

4. Elderly patients have a high incidence of chronic disease states.

5. Elderly patients do not require a "special" anesthetic but rather require strict attention to meticulous preoperative assessment, detailed management of intraoperative variables and concurrent disease states, and cautious titration of drug administration and dosages.

In developed countries the elderly population is growing at a remarkable rate, with considerable implications for perioperative health care. Elderly patients now account for more than half of all hospital care days in the United States. In addition, almost a third of all surgical patients are 65 years or older, with an even larger fraction anticipated in the next 2 decades. Virtually every nonpediatric hospital provides a wide range of surgical services for elderly adults; consequently, almost every anesthesiologist in contemporary practice is expected to have expertise in geriatric medicine as it relates to anesthetic practice.1

As they age, adults exhibit an increasingly varied array of physical responses to lifelong exposure to environmental and socioeconomic conditions and to the accumulated stigmata of prior traumatic injuries and medical therapies. Prolonged longevity also reveals all intrinsic physiologic strengths and weaknesses and full expression of genetic differences that might not be fully apparent over shorter life-span intervals. The terms elderly and geriatric are used synonymously in this chapter to describe patients who are 65 years or older. The term aged is used to describe individuals older than 80 years.

Neither elderly nor aged surgical patients require a "special" anesthetic. A well-conducted anesthetic of any type can be both safe and appropriate for an elderly patient if the anesthesiologist (1) adheres to high standards of preoperative assessment, (2) closely controls and monitors preexisting disease, and (3) pays meticulous attention to drug dosage and to the details of pain management and postoperative care.2 The sections that follow describe some of the current concepts of human aging that are relevant to contemporary anesthetic practice, examine common disease states, and review common surgical procedures in the elderly.

The exact mechanisms that control the aging process remain unknown. However, it is very clear that aging is not simply the result of accumulated disease. Aging is a physiologic phenomenon that manifests itself in mammalian species as universal and progressive degenerative changes in both the structure and the functional capacity of organs and tissues. The implied consequence of aging in all species is an increasing probability of death as a function of time. Currently, there is no consensus as to when the geriatric era begins in human subjects or whether any single physiologic marker can identify an elderly or an aged patient.

Theories proposed to explain aging broadly fall into 3 ...