have become quite ill, they—and those close to them—may still change their perceptions of the benefits and burdens of continuing or foregoing treatment. A large study of seriously ill hospitalized patients found that most patients desired cardiopulmonary resuscitation during their initial interview and 70 percent expressed that preference two months later. Of those preferring resuscitation initially, 85 percent maintained that view whereas of those preferring no resuscitation, 69 percent sustained that view (Rosenfeld, Wenger, et al., 1996). Dialysis patients in another study varied greatly in their desires that previously prepared advance directives be followed as compared with allowing surrogates to exercise discretion (Sehgal, 1992). Given these considerations, communication about goals, options, and preferences should not be envisioned as a single event but as a process that occurs as a patient moves toward death.
Overall, experience with advance care planning indicates that continued investigation is needed to determine the value and limits of such planning and the factors that make it more or less likely to occur and to be helpful to patients and clinicians. The general literature on decisionmaking and decision implementation and the research on advance care planning specifically suggest that effective advance care planning depends on several factors (see, e.g., Lo et al., 1986; Brunetti et al., 1991; Emanuel, 1991; Sachs et al., 1992; Emanuel, 1994; Emanuel and Emanuel, 1994; Morrison et al., 1994; Virmani et al., 1994; Emanuel et al., 1995; Lo, 1995; SUPPORT Principal Investigators, 1995). These factors include: