Adequate antibiotic therapy prior to ICU admission in patients with severe sepsis and septic shock reduces hospital mortality

Introduction: In patients with severe sepsis and septic shock as cause of Intensive Care Unit (ICU) admission, we analyze the impact on mortality of adequate antimicrobial therapy initiated before ICU admission. Methods: We conducted a prospective observational study enrolling patients admitted to the ICU with severe sepsis or septic shock from January 2008 to September 2013. The primary end-point was in-hospital mortality. We considered two groups for comparisons: patients who received adequate antibiotic treatment before or after the admission to the ICU. Results: A total of 926 septic patients were admitted to ICU, and 638 (68.8%) had available microbiological isolation: 444 (69.6%) received adequate empirical antimicrobial treatment prior to ICU and 194 (30.4%) after admission. Global hospital mortality in patients that received treatment before ICU admission, between 0-6h ICU, 6-12h ICU, 12-24h ICU and after 24 hours since ICU admission were 31.3, 53.2, 57.1, 50 and 50.8% (p<0.001). The multivariate analysis showed that urinary focus (odds ratio (OR) 0.20; 0.09-0.42; p<0.001) and adequate treatment prior to ICU admission (OR 0.37; 0.24-0.56; p<0.001) were protective factors whereas APACHE II score (OR 1.10; 1.07-1.14; p<0.001), septic shock (OR 2.47; 1.57-3.87; p<0.001), respiratory source (OR 1.91; 1.12-3.21; p=0.016), cirrhosis (OR 3.74; 1.60-8.76; p=0.002) and malignancy (OR 1.65; 1.02-2.70; p=0.042) were variables independently associated with in-hospital mortality. Adequate treatment prior to ICU was a protective factor for mortality in patients with severe sepsis (n=236) or in septic shock (n=402). Conclusions: The administration of adequate antimicrobial therapy before ICU admission is decisive for the survival of patients with severe sepsis and septic shock. Our efforts should be directed to assure the correct administration antibiotics before ICU admission in patients with sepsis.