917 Epidemiology of Catheter-Related Bloodstream Infections in Quebec Intensive Care Units

Sunday, March 21, 2010
Grand Hall (Hyatt Regency Atlanta)
Patricia S. Fontela, MD, MSc, PhD(c) , McGill University, Montreal, QC, Canada
Robert W. Platt, PhD , McGill University, Montreal, QC, Canada
Isabelle Rocher, BScN, MSc , Institut National de Sante Publique du Quebec, Montreal, QC, Canada
Charles Frenette, MD , McGill University Health Centre, Montreal, QC, Canada
Elise Fortin, MSc , Institut National de Sante Publique du Quebec, Montreal, QC, Canada
Dorothy Moore, MD, PhD , Montreal Children's Hospital, Montreal, QC, Canada
Madhukar Pai, MD, PhD , McGill University, Montreal, QC, Canada
David Buckeridge, MD, PhD , McGill University, Montreal, QC, Canada
Caroline Quach, MD, MSc , Montreal Children's Hospital, Montreal, QC, Canada
Background: Catheter-related bloodstream infections (CR-BSI) are a major problem in intensive care units (ICUs). They are associated with high case-fatality proportion, prolonged hospital stays and increased costs. Despite their clinical and public health importance, little is known about the epidemiology of CR-BSI in Canada. In 2003, the Institut National de Santé Publique du Québec launched the Surveillance Provinciale des Infections Nosocomiales (SPIN) program -- a continuous surveillance program that aims to gather data about ICU CR-BSI incidence and mortality rates.
Objective: To describe the epidemiology and pathogens causing CR-BSI in Quebec ICUs from 2003 to 2009.
Methods: Prospective dynamic cohort of all ICUs that participated in SPIN for at least 6 months in a year between 2003 and 2009. Our primary variable was the annual CR-BSI incidence rates. Secondary variables included annual central venous catheter utilization ratios (CVCUR) and CR-BSI case-fatality proportions, as well as the annual distribution of CR-BSI pathogens and their antimicrobial resistance patterns. Median, percentiles and frequency distributions were used to summarize the study variables.
Results: The 58 ICUs (46 adult, 5 pediatric and 7 neonatal units) in the cohort had a total of 890 CR-BSIs identified in 446,137 CVC-days monitored over the 6-year study interval. The annual incidence rates of CR-BSI were the highest in neonatal ICUs, ranging from 2.71 to 5.69 CR-BSI/1,000 CVC-days, while adult and pediatric ICUs (PICUs) had incidence rates that varied from 1.33 to 1.89 and from 1.38 to 2.84 CR-BSI/1,000 CVC-days, respectively. Since 2007, the CR-BSI rates in adult and pediatric ICUs have steadily declined (by 11 and 50%, respectively). For NICUs, a decrease of 18% in the CR-BSI rate was only detected during the 2008-2009 period. PICUs had the highest annual CVCURs (median 0.61, interquartile range (IQR) 0.57-0.66). Among adult ICUs, the annual CVCUR for teaching ICUs (median 0.61, IQR 0.59-0.64) was between 1.7 and 2.0 times that for non-teaching units (median 0.34, IQR 0.33-0.35). Adult ICUs had the highest annual case-fatality proportions (median 34%, IQR 32-37%), while NICUs had the lowest (median 14%, IQR 9-16%). Coagulase-negative staphylococcus was the most frequent pathogen causing CR-BSI (53%), followed by Staphylococcus aureus (15%) and Candida sp. (13%). Methicillin-resistant S. aureus (MRSA) represented 59% of S. aureus isolated in 2005 and declined to below 40% after 2006.
Conclusions: CR-BSIs occur frequently in Quebec ICUs and result in a considerable burden of illness. However, CR-BSI incidence rates have steadily decreased since 2007 and the proportion of MRSA has remained below 40% after 2006. In order to determine if these changes in the CR-BSI rates and resistance patterns will be maintained, it is essential to pursue surveillance in a continuous fashion.