What is Pediatric Risk of Mortality (PRISM)?

From the Guidelines

PRISM (Pediatric Risk of Mortality) is a scoring system used to assess the severity of illness and predict mortality risk in critically ill children, with the most recent version being PRISM III, which is calculated from 72 worst-in-24-h variables. This scoring system is essential in pediatric intensive care units to evaluate the severity of illness and predict mortality risk 1. The PRISM score takes into account multiple physiological variables, including vital signs, laboratory values, and neurological status, to generate a numerical score that correlates with mortality risk.

Key Components of PRISM

• Evaluates multiple physiological variables to generate a numerical score
• Correlates with mortality risk, with higher scores indicating greater predicted mortality
• Typically calculated within the first 24 hours of ICU admission
• Helps in clinical decision-making, resource allocation, quality assessment, and comparing outcomes across different institutions

The PRISM scoring system has evolved through several versions, with each update refining the variables and improving predictive accuracy 1. However, it is worth noting that PRISM and other severity-of-illness scores, such as the Paediatric Index of Mortality (PIM), do not correctly predict the mortality of infants less than 1 month of age 1. In such cases, alternative scoring systems like the Clinical Risk Index for Babies (CRIB) may be more appropriate 1.

Clinical Applications of PRISM

• Quantifying illness severity to guide treatment intensity
• Communicating prognosis to families based on statistical outcomes
• Comparing outcomes across different institutions to evaluate quality of care
• Informing resource allocation and clinical decision-making in pediatric intensive care units

From the Research

Definition of PRISM

• The Pediatric Risk of Mortality (PRISM) score is a system used to predict the mortality risk of pediatric patients in intensive care units (ICUs) 2.
• It was developed from the Physiologic Stability Index (PSI) to reduce the number of physiologic variables required for pediatric ICU mortality risk assessment and to obtain an objective weighting of the remaining variables 2.

Components of PRISM

• The PRISM score consists of 14 routinely measured physiologic variables and 23 variable ranges 2.
• The score has undergone updates, with the third-generation PRISM III score including 17 physiologic variables subdivided into 26 ranges 3.

Validation and Performance of PRISM

• The PRISM score has been validated in various studies, demonstrating excellent predictor performance and accuracy in predicting mortality risk 2, 4, 3, 5.
• The score has been shown to be effective in differentiating between survivors and non-survivors, with a satisfactory discriminatory performance 4, 5.
• However, some studies have noted that the PRISM score may overestimate mortality in certain pediatric populations 6, 5.

Applications and Limitations of PRISM

• The PRISM score is used in pediatric ICUs to predict mortality risk and evaluate the effectiveness of treatment 2, 4, 5.
• The score can be used to identify patients at high risk of mortality and to guide treatment decisions 4, 5.
• However, the score may not be suitable for all pediatric populations, and its performance may vary depending on the specific population and ICU setting 6, 5.