Introduction
Nosocomial infections (NI) include all infections acquired between 48 hours after hospital admission and 2 days of hospital discharge. As everyone knows, cardiac surgical intensive care unit (ICU) is a special ward with higher incidence of NI and usage rate of antibiotics owing to severity of illness, complexity of surgery and common use of invasive devices (endotracheal tubes, central venous catheters, peripheral arterial catheters and urinary catheters) [1]. NI are associated with increased mobidity and mortality, as well as length of ICU stay and healthcare costs [2,3]. Furthermore, the burden of antimicrobial resistance in ICU is growing high, which has been attributed to the increased difficulty of clinical treament and hospital control of NI. So treatment should be converted into organism-specific treatment from experiential use of antibiotics as soon as possible. The aims of our study were to investigate the characteristics of distribution of pathogenic bacteria and antibiotics resistance of NI.