The Changing Prognostic Determinants in the Critically III Patient

Abstract

The science and art of risk stratification appeared in early 1953, when Virginia Apgar [1] published a simple physiological scoring tool to evaluate the newborn child. This system, still commonly used worldwide, evaluates only two physiologic systems: Cardiopulmonary and central nervous system (CNS) function. Several years later, in the early 1980s, several researchers applied the same concept to critically ill patients, through the introduction of the acute physiology and chronic health evaluation (APACHE) and the simplified acute physiological score (SAPS), both physiologically based classification systems [2, 3]. These instruments, named general severity scores, are tools that aim at stratifying patients based on their severity, assigning to each patient an increasing score as their severity of illness increases. Initially designed to be applicable to individual patients, it became apparent very early after their introduction that both systems could in fact be used only in large heterogeneous groups of critically ill patients.