The National Health Safety Network (NHSN) established new definitions for common healthcare-associated infections (HAIs) in 2015 to address a disturbing problem: Even experienced infection preventionists frequently failed to know when a condition met the previous NHSN definitions.
Hebden and colleagues reported that just 83 (27.9%) of 297 respondents who evaluated nine case studies published in a supplement in the American Journal of Infection Control in 2013 passed with a score of 80% or higher on their first attempt. The overall correct response rate was 64.6%. Even respondents who had more than 10 years of experience had a correct response rate of less than 70%.
In another study, 113 members of the Society for Healthcare Epidemiology of America (SHEA) Research Network representing 61 non-pediatric hospitals reviewed six clinical vignettes. Despite the respondents having an average of 12 years of infection prevention experience, the mean percentage of correct responses was just 61.1%, with a range of 27.4% for a C. difficile scenario to 87.5% for a central line associated bloodstream infection (CLABSI) scenario. The researchers concluded that “more reproducible definitions of HAIs--or even new approaches to HAI surveillance, such as electronic surveillance--are urgently needed.”
NHSN responded to the issues raised by these studies and others by revising the definitions of HAIs to reduce ambiguity, decrease subjectivity, increase clinical relevance and maintain epidemiologic standardization. The new definitions will provide the baseline for calculating standardized infection ratios (SIRs) starting in 2016. While NHSN does not plan to make further revisions to the definitions in the short-term, it does expect to rely on electronic capture of required data and determination of events in the next three to five years.
Joan Hebden, RN, MS, CIC led a recent webinar that reviewed the specific changes to the NHSN definitions for healthcare-associated infections:
New seven-day window: NHSN eliminated the gap day previously used in defining site-specific infection and established a seven-day window during which all site-specific infection criteria must be met. The window starts three days before a positive diagnostic test or first date of localized signs and symptoms develop and extends for three calendars after. The infection window period does not apply to surgical site infection, ventilator-associated event (VAE) or LabID event surveillance. Site-specific infection criterion may include the date of laboratory specimen collection, imaging test, procedure or exam, physician diagnosis or initiation of treatment.
Clarification of present on admission or healthcare-associated infections: NHSN now considers the date of event to be when the first element of the infection criteria is met (does not apply to ventilator-associated events or LabID surveillance). A present-on-admission infection has elements that occur on the day of admission, two days prior to admission or one day after admission. For healthcare-associated infections, all site-specific elements occur on or after the third calendar day of admission.
Repeat infection time (RIT): If an infection of the same type occurs during a 14 day period, with day 1 as the date of the event of the first infection, it cannot be reported as a new infection. If additional site-specific specimens are collected within the RIT and NEW pathogens are detected, ADD to the original infection documentation.
Secondary bloodstream attribution: A reportable secondary bloodstream occurs within the 17 days that apply to the primary infection--the three-day window before the first element of the infection is met plus the 14 days for a potential repeat infection. VAE, surgical site infections and LabID events are exceptions to this definition.
The webinar provides additional information on these definitions and reviews how the new definitions apply to a series of clinical scenarios, offering valuable context and detail for everyone involved in infection prevention.
How has your hospital raised awareness of the new NHSN definitions?