Zimmerman JE, Kramer AA, McNair DS, et al. Acute Physiology and Chronic Health Evaluation (APACHE) IV: Hospital mortality assessment for today’s critically ill patients

George Washington University, Washington, Washington, D.C., United States
Critical Care Medicine (Impact Factor: 6.31). 06/2006; 34(5):1297-310. DOI: 10.1097/01.CCM.0000215112.84523.F0
Source: PubMed


To improve the accuracy of the Acute Physiology and Chronic Health Evaluation (APACHE) method for predicting hospital mortality among critically ill adults and to evaluate changes in the accuracy of earlier APACHE models.
: Observational cohort study.
A total of 104 intensive care units (ICUs) in 45 U.S. hospitals.
A total of 131,618 consecutive ICU admissions during 2002 and 2003, of which 110,558 met inclusion criteria and had complete data.
We developed APACHE IV using ICU day 1 information and a multivariate logistic regression procedure to estimate the probability of hospital death for randomly selected patients who comprised 60% of the database. Predictor variables were similar to those in APACHE III, but new variables were added and different statistical modeling used. We assessed the accuracy of APACHE IV predictions by comparing observed and predicted hospital mortality for the excluded patients (validation set). We tested discrimination and used multiple tests of calibration in aggregate and for patient subgroups. APACHE IV had good discrimination (area under the receiver operating characteristic curve = 0.88) and calibration (Hosmer-Lemeshow C statistic = 16.9, p = .08). For 90% of 116 ICU admission diagnoses, the ratio of observed to predicted mortality was not significantly different from 1.0. We also used the validation data set to compare the accuracy of APACHE IV predictions to those using APACHE III versions developed 7 and 14 yrs previously. There was little change in discrimination, but aggregate mortality was systematically overestimated as model age increased. When examined across disease, predictive accuracy was maintained for some diagnoses but for others seemed to reflect changes in practice or therapy.
APACHE IV predictions of hospital mortality have good discrimination and calibration and should be useful for benchmarking performance in U.S. ICUs. The accuracy of predictive models is dynamic and should be periodically retested. When accuracy deteriorates they should be revised and updated.

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Available from: Andrew A. Kramer, Oct 05, 2015
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    • "Self-fulfilling prophecies have been implicated in mortality rates in hemorrhagic stroke, hypoxic brain injury, critical illness more generally, and brain death (Wilkinson and Savulescu, 2011, 162). The authors of the most successful prognostic system, the APACHE IV, repeatedly acknowledge the role that decisions to forego life-sustaining therapy play in determining patient outcomes (Zimmerman et al., 2006, see pp. 1297, 1304, and 1305). 11 Thus, the self-fulfilling prophecy generates not only artificially elevated mortality rates; it also renders clinical experience less reliable as an epistemic guide to likely outcomes. "
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    ABSTRACT: In this essay I examine the formal structure of the concept of futility, enabling identification of the appropriate roles played by patient, professional, and society. I argue that the concept of futility does not justify unilateral decisions to forego life-sustaining medical treatment over patient or legitimate surrogate objection, even when futility is determined by a process or subject to ethics committee review. Furthermore, I argue for a limited positive ethical obligation on the part of health care professionals to assist patients in achieving certain restricted goals, including the preservation of life, even in circumstances in which most would agree that that life is of no benefit to the patient. Finally, I address the objection that professional integrity overrides this limited obligation and find the objection unconvincing. In short, my aim in this essay is to see the concept of futility finally buried, once and for all. © The Author 2015. Published by Oxford University Press on behalf of the Journal of Medicine and Philosophy Inc.
    Journal of Medicine and Philosophy 08/2015; 40(5). DOI:10.1093/jmp/jhv019 · 0.79 Impact Factor
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    • "Multiple scoring systems, including the APS, APACHE II, and APACHE IV, have been used widely in clinical practice to predict outcome in ICU patients [21, 22]. We used the APS, APACHE II, and APACHE IV to evaluate prognoses and analyzed the correlation between these clinical variables and blood physicochemical parameters. "
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    ABSTRACT: Purpose: To determine the influence of physicochemical parameters on survival in metabolic acidosis (MA) and acute kidney injury (AKI) patients. Materials and methods: Seventy-eight MA patients were collected and assigned to AKI or non-AKI group. We analyzed the physiochemical parameters on survival at 24 h, 72 h, 1 week, 1 month, and 3 months after AKI. Results: Mortality rate was higher in the AKI group. AKI group had higher anion gap (AG), strong ion gap (SIG), and apparent strong ion difference (SIDa) values than non-AKI group. SIG value was higher in the AKI survivors than nonsurvivors and this value was correlated serum creatinine, phosphate, albumin, and chloride levels. SIG and serum albumin are negatively correlated with Acute Physiology and Chronic Health Evaluation IV scores. AG was associated with mortality at 1 and 3 months post-AKI, whereas SIG value was associated with mortality at 24 h, 72 h, 1 week, 1 month, and 3 months post-AKI. Conclusions: Whether high or low SIG values correlate with mortality in MA patients with AKI depends on its correlation with serum creatinine, chloride, albumin, and phosphate (P) levels. AG predicts short-term mortality and SIG value predicts both short- and long-term mortality among MA patients with AKI.
    BioMed Research International 08/2014; 2014:819528. DOI:10.1155/2014/819528 · 3.17 Impact Factor
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    • "However, Zimmerman et al. [5] suggested that APACHE IV has better accuracy than the previous systems, and older models should not be used. The APACHE IV model showed good discrimination and calibration in the United States where the model was developed [5]. Outside the United States, recent studies have demonstrated that the discriminatory performance of APACHE IV was good [8,9,10,11,12]. "
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    ABSTRACT: Background The Acute Physiology and Chronic Health Evaluation (APACHE) IV model has not yet been validated in Korea. The aim of this study was to compare the ability of the APACHE IV with those of APACHE II, Simplified Acute Physiology Score (SAPS) 3, and Korean SAPS 3 in predicting hospital mortality in a surgical intensive care unit (SICU) population. Methods We retrospectively reviewed electronic medical records for patients admitted to the SICU from March 2011 to February 2012 in a university hospital. Measurements of discrimination and calibration were performed using the area under the receiver operating characteristic curve (AUC) and the Hosmer-Lemeshow test, respectively. We calculated the standardized mortality ratio (SMR, actual mortality predicted mortality) for the four models. Results The study included 1,314 patients. The hospital mortality rate was 3.3%. The discriminative powers of all models were similar and very reliable. The AUCs were 0.80 for APACHE IV, 0.85 for APACHE II, 0.86 for SAPS 3, and 0.86 for Korean SAPS 3. Hosmer and Lemeshow C and H statistics showed poor calibration for all of the models (P < 0.05). The SMRs of APACHE IV, APACHE II, SAPS 3, and Korean SAPS 3 were 0.21, 0.11 0.23, 0.34, and 0.25, respectively. Conclusions The APACHE IV revealed good discrimination but poor calibration. The overall discrimination and calibration of APACHE IV were similar to those of APACHE II, SAPS 3, and Korean SAPS 3 in this study. A high level of customization is required to improve calibration in this study setting.
    Korean journal of anesthesiology 08/2014; 67(2):115-22. DOI:10.4097/kjae.2014.67.2.115
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