List the desirable features of an Illness Severity Scoring System for Intensive Care patients.? Compare and contrast the Acute Physiology and Chronic Health Evaluation (APACHE) and Sequential Organ Failure Assessment (SOFA) scoring systems.
The ideal scoring system would have the following characteristics:
1. Scores calculated on the basis of easily/routinely recordable variables
2. Well calibrated
3. A high level of discrimination
4. Applicable to all patient populations in ICU
5. Can be used in different countries
6. The ability to predict mortality,functional status or quality of life after ICU discharge
Compare
APACHE |
SOFA |
|
Basis |
Three factors that influence |
Degree of organ |
Score |
Physiological variables, |
Defined score ( 1-4) for |
Scoring duration |
Based on the most abnormal |
Daily scoring of individual |
Population Outcome |
Standardized mortality |
No predicted mortality Treatment effects on SOFA |
Individual patient outcomes |
Not possible to predict |
Response of organ |
The various illness severity scoring systems are summarised elsewhere.
LITFL gives the a list of qualities for the "ideal" ICU scoring system. In his 2010 review of scoring systems, Jean-Louis Vincent also gives this list of "ideal" features.
I have incorporated these opinions into one master list of ideal features.
A comparison of SOFA and APACHE as a table is discussed in detail elsewhere; I will merely reproduce the comparsion table in the space below.
APACHE |
SOFA |
|
Basic premise |
ICU mortality depends on three domains:
Thus, if one can quantify these domains, one may be able to predict mortality on the basis of such measurements. |
Degree of organ dysfunction is related to acute illness. Originally designed with sepsis in mind, but subsequently validated in other disease states. |
Measured parameters |
Heuristic groupings of 12 physiologic variables, Glasgow Coma Score (GCS), age, and chronic health evaluation status. |
6 domains of organ system function |
Measurement collection |
Worst score within the first 24 hours |
Daily measurement of |
Unique features |
Incorporates chronic illness, emergency admission, age, surgical vs non-surgical admission, and cardiorespiratory arrest |
Incorporates the use of organ system support sug as vasopressors and dialysis |
Scoring |
0 to 71 |
0 to 24 |
Mortality prediction |
The risk of hospital death is computed by combining APACHE II score with Knaus' |
SOFA does not predict mortality, and the original authors intended it to be used as a means of reproduceably describing a sequence of complications in the critically ill. That said, higher SOFA scores are in factassociated with increased mortality. |
Prognostic value |
APACHE is a poor predictor of individual patient outcome. |
One can monitor response to therapy by the change of daily SOFA scores |
Balci, C., et al. "[APACHE II, APACHE III, SOFA scoring systems, platelet counts and mortality in septic and nonseptic patients]." Ulusal travma ve acil cerrahi dergisi= Turkish journal of trauma & emergency surgery: TJTES 11.1 (2005): 29-34.
Halim, Dino Adrian, Tri Wahyu Murni, and Ike Sri Redjeki. "Comparison of Apache II, SOFA, and Modified SOFA scores in predicting mortality of surgical patients in intensive care unit at Dr. Hasan Sadikin General Hospital." Critical Care & Shock 12 (2009): 157-169.
Knaus, William A., et al. "APACHE II: a severity of disease classification system." Critical care medicine 13.10 (1985): 818-829.
Vincent, J-L., et al. "The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure." Intensive care medicine 22.7 (1996): 707-710.
Ferreira, Flavio Lopes, et al. "Serial evaluation of the SOFA score to predict outcome in critically ill patients." Jama 286.14 (2001): 1754-1758.
Vincent, Jean-Louis, and Rui Moreno. "Clinical review: scoring systems in the critically ill." Crit Care 14.2 (2010): 207.
Livingston, Brian M., et al. "Assessment of the performance of five intensive care scoring models within a large Scottish database." Critical care medicine28.6 (2000): 1820-1827.
Wong, David T., et al. "Evaluation of predictive ability of APACHE II system and hospital outcome in Canadian intensive care unit patients." Critical care medicine 23.7 (1995): 1177-1183.