William A. Knaus

APACHE-acute physiology and chronic health evaluation: a physiologically based classification system.

&NA; Investigations describing the utilization pattern and documenting the value of intensive care are limited by the lack of a reliable and valid classification system. In this paper, the authors describe the development and initial validation of acute physiology and chronic health evaluation (APACHE), a physiologically based classification system for measuring severity of illness in groups of critically ill patients. APACHE uses information available in the medical record. In studies on 582 admissions to a university hospital ICU and 223 admissions to a community hospital ICU, APACHE was reliable in classifying ICU admissions. In validation studies involving these 805 admissions, the acute physiology score of APACHE demonstrated consistent agreement with subsequent therapeutic effort and mortality. This was true for a broad range of patient groups using a variety of sensitivity analyses. After successful completion of multi‐institutional validation studies, the APACHE classification system could be used to control for case mix, compare outcomes, evaluate new therapies, and study the utilization of ICUs.

An evaluation of outcome from intensive care in major medical centers

We prospectively studied treatment and outcome in 5030 patients in intensive care units at 13 tertiary care hospitals. We stratified each hospitals patients by individual risk of death using diagnosis, indication for treatment, and Acute Physiology and Chronic Health Evaluation (APACHE) II score. We then compared actual and predicted death rates using group results as the standard. One hospital had significantly better results with 69 predicted but 41 observed deaths (p less than 0.0001). Another hospital had significantly inferior results with 58% more deaths than expected (p less than 0.0001). These differences occurred within specific diagnostic categories, for medical patients alone and for medical and surgical patients combined, and were related more to the interaction and coordination of each hospitals intensive care unit staff than to the units administrative structure, amount of specialized treatment used, or the hospitals teaching status. Our findings support the hypothesis that the degree of coordination of intensive care significantly influences its effectiveness.

Prognosis in acute organ-system failure.

This prospective study describes the current prognosis of patients in acute Organ System Failure (OSF). Objective definitions were developed for five OSFs, and then 5677 ICU admissions from 13 hospitals were monitored. The number and duration of OSF were linked to outcome at hospital discharge for each of the 2719 ICU patients (48%) who developed OSF. For all medical and most surgical admissions, a single OSF lasting more than 1 day resulted in a mortality rate approaching 40%. Among both medical and surgical patients, two OSFs for more than 1 day increased death rates to 60%. Advanced chronologic age increased both the probability of developing OSF and the probability of death once OSF occurred. Mortality for 99 patients with three or more OSFs persisting after 3 days was 98%. The two patients who survived were both young, in prior excellent health, and had severe but limited primary diseases. These results emphasize the high death rates associated with acute OSF and the rapidity with which mortality increases over time. The prognostic estimates provide reference data for physicians treating similar patients.

THE PERFORMANCE OF INTENSIVE CARE UNITS : DOES GOOD MANAGEMENT MAKE A DIFFERENCE ?

A significant portion of health care resources are spent in intensive care units with, historically, up to two-fold variation in risk-adjusted mortality. Technological, demographic, and social forces are likely to lead to an increased volume of intensive care in the future. Thus, it is important to identify ways of more efficiently managing intensive care units and reducing the variation in patient outcomes. Based on data collected from 17,440 patients across 42 ICUs, the present study examines the factors associated with risk-adjusted mortality, risk-adjusted average length of stay, nurse turnover, evaluated technical quality of care, and evaluated ability to meet family member needs. Using the Apache III methodology for risk-adjustment, findings reveal that: 1) technological availability is significantly associated with lower risk-adjusted mortality (beta = -.42); 2) diagnostic diversity is significantly associated with greater risk-adjusted mortality (beta = .46); and 3) caregiver interaction comprising the culture, leadership, coordination, communication, and conflict management abilities of the unit is significantly associated with lower risk-adjusted length of stay (beta = .34), lower nurse turnover (beta = -.36), higher evaluated technical quality of care (beta = .81), and greater evaluated ability to meet family member needs (beta = .74). Furthermore, units with greater technological availability are significantly more likely to be associated with hospitals that are more profitable, involved in teaching activities, and have unit leaders actively participating in hospital-wide quality improvement activities. The findings hold a number of important managerial and policy implications regarding technological adoption, specialization, and the quality of interaction among ICU team members. They suggest intervention “leverage points” for care givers, managers, and external policy makers in efforts to continuously improve the outcomes of intensive care.

APACHE II-A Severity of Disease Classification System: Reply

This paper presents the form and validation results of APACHE II, a severity of disease classification system. APACHE II uses a point score based upon initial values of 12 routine physiologic measurements, age, and previous health status to provide a general measure of severity of disease. An increasing score (range 0 to 71) was closely correlated with the subsequent risk of hospital death for 5815 intensive care admissions from 13 hospitals. This relationship was also found for many common diseases.When APACHE II scores are combined with an accurate description of disease, they can prognostically stratify acutely ill patients and assist investigators comparing the success of new or differing forms of therapy. This scoring index can be used to evaluate the use of hospital resources and compare the efficacy of intensive care in different hospitals or over time.

Advance directives for seriously ill hospitalized patients: Effectiveness with the patient self-determination act and the SUPPORT intervention

OBJECTIVE: To assess the effectiveness of written advance directives (ADs) in the care of seriously ill, hospitalized patients. In particular, to conduct an assessment after ADs were promoted by the Patient Self‐Determination Act (PSDA) and enhanced by the effort to improve decision‐making in the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT), focusing upon the impact of ADs on decision‐making about resuscitation.

Influence of Patient Preferences and Local Health System Characteristics on the Place of Death

OBJECTIVE: To examine the degree to which variation in place of death is explained by differences in the characteristics of patients, including preferences for dying at home, and by differences in the characteristics of local health systems.

Do Advance Directives Provide Instructions That Direct Care

OBJECTIVE: To evaluate whether the lack of effect of advance directives (ADs) on decision‐making in SUPPORT might arise, in part, from the content of the actual documents.

Improving intensive care : observations based on organizational case studies in nine intensive care units : a prospective, multicenter study

To examine organizational practices associated with higher and lower intensive care unit (ICU) outcome performance. Design:Prospective multicenter study. On-site organizational analysis; prospective inception cohort. Setting:Nine ICUs (one medical, two surgical, six medical-surgical) at five teaching and four nonteaching hospitals. Participants:A sample of 3,672 ICU admissions; 316 nurses and 202 physicians. Materials and Methods:Interviews and direct observations by a team of clinical and organizational researchers. Demographic, physiologic, and outcome data for an average of 408 admissions per ICU; and questionnaires on ICU structure and organization. The ratio of actual/predicted hospital death rate was used to measure ICU effectiveness; the ratio of actual/predicted length of ICU stay was used to assess efficiency. Measurements and Main Results:ICUs with superior risk-adjusted survival could not be distinguished by structural and organizational questionnaires or by global judgment following on-site analysis. Superior organizational practices among these ICUs were related to a patient-centered culture, strong medical and nursing leadership, effective communication and coordination, and open, collaborative approaches to solving problems and managing conflict. Conclusions:The best and worst organizational practices found in this study can be used by ICU leaders as a checklist for improving ICU management. (Crit Care Med 1993; 21:1443–1451)

Impact of Patient Distance to Radiation Therapy on Mastectomy Use in Early-Stage Breast Cancer Patients

PURPOSE Treatment access underlies quality cancer care. We hypothesize that mastectomy rates in a rural state are independently influenced by distance to radiation therapy (XRT) and by changing XRT access through opening new facilities. PATIENTS AND METHODS Early-stage breast cancer patients diagnosed from 1996 to 2000 were identified in the Virginia state registry. Distance from patient zip code to nearest XRT facility was calculated with geographical software. Distance to XRT facility (< or = 10, > 10 to 25, > 25 to 50, and > 50 miles), American Joint Committee on Cancer tumor stage, age, race, and diagnosis year were evaluated for influencing mastectomy rate. Mastectomy use within 15 miles of five new facilities was assessed before and after opening. RESULTS Among 20,094 patients, 43% underwent mastectomy, 53% underwent lumpectomy, and therapy of 4% of patients is unknown. Twenty-nine percent of patients lived more than 10 miles from XRT facility. Mastectomy increased with distance to XRT facility (43% at < or = 10 miles, 47% at > 10 to 25 miles, 53% at > 25 to 50 miles, and 58% at > 50 miles; P < .001). Among 11,597 patients with T1 (< 2 cm) tumors, mastectomy also varied by distance (31% at < or = 10 miles, 36% at > 10 to 25 miles, 41% at > 25 to 50 miles, and 49% at > 50 miles; P < .001). In multivariate analysis, mastectomy use was independently influenced by XRT distance after adjusting for age, race, T stage, and diagnosis year. Over the study period, mastectomy rates declined from 48% to 43% across Virginia, and there were similar declines in a 15-mile area around four new radiation facilities in urban settings. However, mastectomies decreased from 61% to 45% around a new XRT facility in a rural setting. CONCLUSION Distance to XRT facility significantly impacts mastectomy use. Opportunities for increasing breast-conservation rates through improved XRT access exist.