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Instrument Summary for Mortality

Please note that this section is an archive and is no longer being updated.

Development: In 1978, William Knaus and colleagues at George Washington University developed the APACHE system to collect data from intensive care patients and computerize it into a total sum of relevant variables. Variables and weights were chosen by a panel of experts. Variables include physiological factors, age, and chronic health problems. Observed variables are entered into the system and a prediction of patient hospital death is calculated. The APACHE has undergone several iterations and the most recent version is the APACHE III.

Purpose: The APACHE was originally designed to assess patient mortality rates as a hospital performance indicator.

Useful Facts: The APACHE III compares the patient generated medical profile against more than 15,000 cases from 40 U.S. hospitals and generates a prognosis that is 95% accurate on average. It is appropriate for mortality prediction in intensive care units and critical care patients.

VA Relevance: The APACHE system has been utilized with veterans.

Availability: The APACHE III may be obtained from Cerner Corporation. Contact information is on their website.

References:

1. Knaus WA, Draper EA, Wagner DP, Zimmerman JE. APACHE II: a severity of disease classification system.Crit Care Med. 1985 Oct;13(10):818-29. [Abstract ]
2. Wong DT, Knaus WA. Predicting outcome in critical care: the current status of the APACHE prognostic scoring system.Can J Anaesth. 1991 Apr;38(3):374-83. Review. [Abstract ]
3. Knaus WA. APACHE 1978-2001: the development of a quality assurance system based on prognosis: milestones and personal reflections.Arch Surg. 2002 Jan;137(1):37-41. [Abstract ]

Development: The Simplified Acute Physiology Score (SAPS) is based on the APACHE system. The variables and weights were chosen by a panel of experts. It utilizes 14 of the 34 APACHE variables used to predict mortality. The second iteration of the SAPS (SAPS II) was based on 12 physiological factors, age, type of admission, and chronic health conditions.

Purpose: To provide a severity score for intensive care unit patients and to provide probability of hospital mortality.

Useful Facts: The original SAPS system contained data on 8500 patients. The SAPS III was recently developed by the SAPS III Outcomes Research Group, and the main reports of that project will be published in the journal of Intensive Care Medicine. The update will include a mortality prediction equation and will incorporate reason for admission, more comorbidity options, and patient location prior to admission.

VA Relevance: The SAPS has been utilized with veterans.

Availability: The SAPS may be obtained from the SAPS 3 Outcome Research Group website.

References:

1. Le Gall JR, Lemeshow S, Saulnier F. A new Simplified Acute Physiology Score (SAPS II) based on a European/North American multicenter study. JAMA. 1993 Dec 22-29;270(24):2957-63. Erratum in: JAMA 1994 May 4;271(17):1321. [Abstract ]
2. Vazquez G, Benito S, Rivera R. Spanish Project for the Epidemiological Analysis of Critical Care Patients. Simplified Acute Physiology Score III: a project for a new multidimensional tool for evaluating intensive care unit performance. Crit Care. 2003 Oct;7(5):345-6. Epub 2003 Mar 3. [Abstract ]
3. SAPS III Outcome Research Group. Accessed July 2005. Available: http://www.saps3.org

Development: The first Mortality Probability Model (MPM) was developed in 1989 on an international sample of 12,610 intensive care unit patients. Data were collected in 139 hospital intensive care units in 12 countries. The MPM uses a multiple logistic regression model to predict the risk of death based on weighted variables. The initial admission model contained 15 readily obtainable variables and the 24-hour model (to be given 24 hours after admission) contained eight variables in addition to the admission variables. Newer models allow assessment at 48 and 72 hours post-admission.

Purpose: To estimate the probability of hospital mortality.

Useful Facts: The MPM system is divided into two models, one to be used upon admission and the other appropriate 24 hours after admission to the intensive care unit, tailored to more complex patients. The MPM contains chronic and acute condition diagnoses as variables, although users do not have to decide on just one diagnosis in order to use the models.

VA Relevance: The MPM has been utilized with veterans.

Availability: The list of variables can be found in Lemeshow et al. 1993, JAMA 270(20), 2478. To calculate the probability online, a probability template is available. Templates are available for the admission model and 24-hour, 48-hour, and 72-hour models.

References:

1. Lemeshow S, Teres D, Klar J, Avrunin JS, Gehlbach SH, Rapoport J. Mortality Probability Models (MPM II) based on an international cohort of intensive care unit patients. JAMA. 1993 Nov 24;270(20):2478-86. [Abstract ]
2. Lemeshow S, Klar J, Teres D, Avrunin JS, Gehlbach SH, Rapoport J, Rue M. Mortality probability models for patients in the intensive care unit for 48 or 72 hours: a prospective, multicenter study. Crit Care Med. 1994 Sep;22(9):1351-8. [Abstract ]
3. Beck DH, Taylor BL, Millar B, Smith GB. Prediction of outcome from intensive care: a prospective cohort study comparing Acute Physiology and Chronic Health Evaluation II and III prognostic systems in a United Kingdom intensive care unit.Crit Care Med. 1997 Jan;25(1):9-15. [Abstract ]