Evolving Concepts inSepsis Definitions

To be able to give a clear name or label to a specific collection of signs and symptoms is important for physicians and patients alike. Having an exact diagnosis helps to identify particular groups of patients, to better understand the underlying disease process, and provides a more defined target for appropriate treatment. However, to be able to reach an accurate diagnosis, and hence, offer optimal medical therapy, a precise definition of the disease process in question is required. Over the years many disease processes have become well defined and are fairly easy to diagnose with the appropriate set of symptoms and test results. For example, acute myocardial infarction is associated with typical symptoms (eg, chest pain), signs (eg, abnormal electrocardiogram), and biomarkers (eg, raised blood troponin levels); patients meeting these criteria can be offered immediate and appropriate therapy. Imprecise definitions of disease limit the ability to form a specific, correct diagnosis and attempts to institute or study therapies in such situations are unlikely to be of benefit and may cause harm. In sepsis, attempts have also been made to provide clear and accurate definitions, but these efforts have not met with universal support. In 2004, a survey of 1058 physicians, including 529 intensivists, noted that only 17% of those interviewed agreed on any one definition. Sepsis is a complex process that can affect any individual and can originate from multiple sites and be caused by multiple microorganisms. Sepsis can present with a multitude of signs and symptoms, none of which are specific for sepsis and all of which can vary among patients and within the same patient over time. These symptoms can vary in severity from a mild, short-lived fever to fatal septic shock. Faced with such complexity and variation, it may be that a single, simple definition for sepsis will never be possible and we should focus on types of infection rather than on sepsis per se.