THE SPECTRUM OF SEPTIC ENCEPHALOPATHY - DEFINITIONS, ETIOLOGIES, AND MORTALITIES

Objective.-To determine whether the severity of septic encephalopathy is correlated with gram-negative bacteremia and mortality and whether there exists a single or combination of metabolic derangement(s) that cause septic encephalopathy. Design and Setting.-Prospective case seri es in an academic medical center. Patients.-Fifty patients selected ac cording to clinical and laboratory criteria for severe sepsis. The cri teria included temperature, heart rate, respiratory rate, and hypotens ion and/or signs of systemic hypoperfusion. Main Outcome Measures.-A s ingle or combination of metabolic and laboratory derangements and orga n failures, three different methods to grade the severity of septic en cephalopathy, Acute Physiology and Chronic Health Evaluation II (APACH E II) scores, gram-negative bacteremia and infection, and mortality. R esults.-Encephalopathy was associated with an increase in mortality wh en graded by the Glasgow Coma Score; a score of 15 had 16% mortality, 13 to 14 had 20%, 9 to 12 had 50%, and 3 to 8 had 63% mortality (P<.05 ). Bacteremia was associated with encephalopathy; 13% of septic patien ts without encephalopathy vs 59% of patients with encephalopathy had b acteremia (P<.001) when graded by altered mental status. Septic enceph alopathic patients had elevated serum urea nitrogen and bilirubin leve ls, increased APACHE II scores, and a higher incidence of renal failur e. Conclusions.-The severity of septic encephalopathy correlated with mortality, bacteremia, and renal and hepatic dysfunction. The Glasgow Coma Score is a useful tool for characterizing septic encephalopathy. Considerable variations can be found according to different criteria u sed to classify septic encephalopathy.