Nursing workload not a factor in VRE outbreak
Antibiotic use emerged as risk factor for VRE
The emerging link between infection rates and nursing staff changes may make it tempting to conclude that increases in nursing workload in general will lead to increased patient colonization with nosocomial patho gens. But an epidemiologist who explored this issue found that only prior administration of antibiotics — not nursing workload intensity — was a statistically significant risk factor for subsequent patient colonization with vancomycin-resistant enterococci.1 (See related story, p. 79.)
Mark Loeb, MD, MSc, FRCPC, microbiologist and infectious disease consultant at McMaster University in Hamilton, Ontario, conducted a case-control study to determine whether potentially modifiable risk factors such as antibiotic use and nursing workload intensity were associated with VRE colonization during a 1998 hospital outbreak. The study was reported recently in San Francisco at the annual conference of the Society for Healthcare Epidemiology of America.
"The assumption is that if nurses are working too hard, they can’t pay attention to infection control measures," he tells Hospital Infection Control. "Everyone, the media, says we are getting so much VRE because the nurses are overworked. So we did a study to say, is this true or not? We didn’t find it was true in this study."
Case patients in the study were those who acquired VRE nosocomially (at least 48 hours after admission) during the outbreak period and had at least one negative surveillance swab prior to detection of VRE. Control patients were randomly selected from among patients who did not acquire VRE in the units where VRE was detected. Antibiotic use was determined for up to a 12-week period prior to VRE detection for cases, and for up to a 12-week interval between the first and last negative rectal swabs for controls. Nursing workload intensity was determined daily using the GRASP system, in which standardized nursing time requirements are assigned to nursing interventions as a way to measure workload intensity.2 Only cephalosporin use was independently associated with subsequent VRE colonization in a statistical analysis.
"We found that the nursing workload was not an independent risk factor for VRE," Loeb says. "The point estimate of the odds ratio did show an increased workload in cases as compared to controls, but it wasn’t statistically significant."
A possible reason is that the threshold of workload intensity that would result in increased VRE transmission was not reached, says Loeb, who has submitted the study for publication to a peer-reviewed journal. "The bottom line is that this is not the end of the story," he says. "We need more studies looking at nursing workload and multiresistant organisms, and we need to assess different tools for looking at them as well."
References
1. Loeb M, Salama S, Armstrong-Evans M, et al. Nursing workload was not an independent risk factor for nosocomial colonization with VRE. Abstract 3. Presented at the Conference of the Society for Healthcare Epidemiology of America. San Francisco; April 18-20, 1999.
2. Meyer D. A patient information and workload management system. Morganton, NC: M.C.S.; 1974.
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content