Sepsis is a systemic response to an infection involving one or multiple organ failures frequently caused by bacteremia. Over a million cases of sepsis are reported in the United States annually with an estimated 25% mortality. Early recognition, diagnosis, and treatment of sepsis in the Emergency Department (ED) improves patient outcomes. Increased awareness of sepsis has fostered novel opportunities to improve diagnostics. EDs are increasingly targeted as areas of primary care for suspected septic patients. Understanding the etiology of ED sepsis supports empiric approaches and opportunities for targeted diagnostics. However, a systematic analysis of etiology of ED sepsis, spanning multiple years, is lacking.
A retrospective analysis conducted over 60 months at Hennepin County Medical Center, an inner-city level one trauma center with over 100,000 ED visits annually were examined. Positive blood cultures drawn in the ED were included in data analysis. Charts were reviewed for patient demographics and whether the culture was treated; infections that were not treated were considered contaminants, and relevant susceptibility patterns.
A total of 8,013 blood cultures were drawn in the ED over an initial 12 month period. Of these, 8.4% (n=674) were culture positive resulting in 731 microorganisms. Of these, 314 were treated as infections with the remaining considered contaminants. Overall contamination rate was 2.9%. Of clinically relevant positive blood cultures, 19.4% were Escherichia coli, 18.5% were Staphylococcus aureus, 27.1% were strep species (group A strep 5.4%, group B strep 4.8%, strep pneumonia 5.1%), 7.0% were Enterococcus faecalis, and 6.4% Klebsiella pneumonia. Among these species, they accounted for 78.4% of pertinent positive cultures. Gram negative bacteremias accounted for 41% of infections compared to 59% for gram positive organisms.
A comprehensive understanding of the etiology of ED sepsis facilitates appropriate empiric antimicrobial prescribing for patients who present with sepsis in the ED. Data collected to date identifies five key bacterial species associated with over 78% of confirmed ED sepsis.
E. Wesenberg, None
G. Hansen, None