Admission to an intensive care unit (ICU) is lifesaving for some patients, but for many, the admission carries high expectations and financial costs and fails to provide desirable outcomes. Patients who receive intensive care have a mortality rate of about 20%, and the costs of this care comprise about 4% of the U.S. health care budget.1,2 In a study of Medicare recipients, treatment intensity and expenses increased between the mid-1980s and 1999 but without any increase in survivorship; per capita ICU expenses were higher for patients who did not survive the ICU.3 Use of the ICU in patients’ final stages of life has increased in proportion since then, and the demand for critical care is likely to continue as the relative proportion of elderly patients in the population rises.2,4,5
Physicians and nurses who responded to a European survey on the inappropriateness of intensive care overwhelmingly endorsed the problems of “too much care” (89%) and “other patients would benefit more” (38%).6 Receiving terminal care in the ICU runs counter to the preferences of most patients.7 Therefore, the challenges are to define the true beneficiaries of critical care and to minimize the discomfort and unrealistic expectations of patients who will not benefit from intensive care.
For ICU patients, morbidity and mortality depend on the interaction of an acute insult (or a surgery), major comorbidities, and physiologic reserve. Aside from those with objective criteria of extreme illness, many patients have an indeterminate prognosis that is difficult to reliably predict.8,9 Several prognostic scores, including the APACHE (Acute Physiologic Assessment and Chronic Health Evaluation) and SOFA (Sequential Organ Failure Assessment) scores, have proved useful in understanding the illness burden of a population when comparing outcomes in different ICUs. Yet their use in assessing the survival of individual patients has not been advocated.10-15 The utility of such models is further challenged by the significant differences in survival between patients with similar illness scores; by the sometimes poor applicability of a model’s derivation cohort to other ICU populations (surgical in particular); by cases of huge disparities between actual and predicted mortality; and by the periodic need to recalibrate models according to advances in care.16-20
Physician intuition regarding prognosis is highly variable. In a series of medical (floor and ICU) admissions, resident physician estimates of illness severity and postdischarge status were associated with stepwise differences in mortality and APACHE scores.21,22 However, in a pure ICU population, in most cases seasoned providers could not accurately predict a patient’s chance of survival.23 Physicians are likewise poor in predicting family preferences regarding aggressive care vs alternatives, and often, survival is couched in terms of ICU survival, which for family members may not be as meaningful as long-term survival or functional recovery. Further, quality of life and patient preferences are not discussed in most cases, even those associated with poor outcomes.24 There also is a large amount of heterogeneity in the end of-life care of ICU patients. For example, cardiopulmonary resuscitation was attempted in up to 70% of dying patients in some ICUs and in as little as 4% in other ICUs.25 Thus, the limitations of predictive models, combined with misperceptions of patient preference, poor communication, and local traditions, lead to aggressive care being given to patients who might not benefit from or desire such care.
It has been stated that the trajectory of most critical illness is unclear enough so that patients should be admitted to the ICU for a trial of therapy, and that in outcome predictions, the response to intensive treatment may be more useful than laboratory and other data comprising illness severity scores.15,26 However, there is no consensus as to what constitutes a trial of intensive care therapy—vs a round of chemotherapy, a course of antibiotics, or a palliative ileostomy—yet this is the basis of many ICU admissions. Slight corrections in laboratory or physiologic findings often lead to continuation of aggressive care, often without any discussion of expected outcomes and the process of identifying and caring for patients who do not respond to therapy. Intensive care also may be prolonged because of several medical, personal, and social factors (Table 1).
At best, deciding how long to provide intensive care involves a synthesis of information about the trajectory, physiologic reserve, beliefs, values, and preferences of the patient. Any or all of these elements may not be known to the care decision-makers.
The authors conducted a study to determine whether a particular duration of care exists that represents a reasonable trial of therapy. As the VA Palo Alto Health Care System (VAPAHCS) ICU treats both medical and surgical patients, the authors were able to compare these subpopulations’ outcomes while providing the same standard of care. They analyzed the aggregate of patients as well as the medical and surgical subpopulations.