An Active, Continuously Evolving Infection Control Program can Reduce Rates of Nosocomial MRSA by Targeted Sustained Actions

by Ann Higgins, RGN, RSCN, H Dip Infection Control
Mater Private Hospital, Dublin, Ireland

Editor’s Note

This article was originally presented as a poster at the 2006 Joint Commission International (JCI) Hospital Executive Briefings in Dublin, Ireland. Mater Private Hospital is a JCI-accredited organization. The author may be contacted at ahiggins@materprivate.ie.

Introduction
The author has been working as an infection control nurse in a 168-bed acute tertiary referral hospital since 1995. This paper recounts a ten-year history of the incidence of methicillin-resistant Staphylococcus aureus (MRSA) in this hospital and describes the changes in the infection control program that led to a sustained reduction in nosocomial (health care–acquired) MRSA.

Objectives and Methods
The main objective of the study was to provide an understanding of factors affecting MRSA acquisition, and in this way, reduce the risk to patients by targeted sustained actions. This prospective study began in 1995 and is ongoing today.

The rates of nosocomial MRSA in the hospital are recorded per 100 admissions and per 1,000 bed days. Numbers of patients noted to be MRSA positive on admission are also recorded. Those colonized with MRSA and those with MRSA infection are included in the figures.

At the end of each year, the results are discussed at the Infection Control Committee and staff are provided with feedback at department level. Adjustments are then made to the Infection Control Program to ensure any issues identified during the previous year are addressed.

1996–1998 During the first few years of the study, education of staff centered on Standard and Contact Precautions. Patient screening for MRSA was limited to screening pre-operative cardiac surgery patients and long-stay intensive therapy unit (ITU) patients. All patients found to be MRSA positive were nursed in single rooms until 3 negative screens or until discharge from the hospital.

1997 Nasal Mupiricin was introduced for all pre-operative cardiac surgery cases on foot of research that found it reduced the incidence of sternal wound infections in clean surgery.¹ Otherwise, practice related to MRSA was unchanged in the period 1996–1999 inclusive.

1999 A small outbreak occurred in the Cardiac ward, which lasted 3 months and involved 14 patients becoming colonized with MRSA in groin and perineal areas. The source was identified as a shower seat in a newly installed shower unit in the step-down area. This outbreak demonstrated how even one unknown carrier could have major implications for high-risk patients. It was the catalyst required to step up our management of MRSA.

2000 A search-and-destroy program for MRSA was launched that aimed to reduce MRSA rates and identify carriers on admission. This involved a multifaceted approach to MRSA management within the organization as follows:

• All patients transferred from other hospitals, nursing homes, etc., and those with history of MRSA are screened on admission for MRSA.
• All pre-operative cardiac patients continue to be screened
• All patients with a history of MRSA are admitted to single rooms pending screening results
• All patients with MRSA regardless of site nursed in single rooms until 3 negative screens or discharge.
• The staff education program was intensified and expanded to include contract cleaning staff, portering staff, and ancillary staff.
• The program provided annual feedback to all staff on MRSA rates and updates on hand hygiene and standard Precautions.

The author recognizes the fact that many hospitals do not have the significant number of single rooms available to carry out this process. However, in this hospital, availability was not an issue once the there was liaison with bed management staff.

Results
The average rate of nosocomial MRSA during the first four years of the program was 0.29 per 100 admissions. After introduction of the search-and-destroy program in January 2000, these rates began to fall. In 2000 and 2001, nosocomial MRSA rates dropped to 0.1 per 100 admissions. Even taking into account annual variances, this was a statistically significant reduction. (see Figure 1 below)

Figure 1

2002–2003 The MRSA rates increased to 0.2 per 100 admissions. A review of practice was undertaken and a number of recommendations made:

• As the majority of patients for Cardiac surgery were transferred from other hospitals and thus were at increased risk of MRSA colonization, it was decided that antibiotic prophylaxis should be changed to provide MRSA cover for this group of patients.
• Movement of patients within the Cardiac unit increased the numbers of patients and rooms exposed to any single unknown MRSA case. Thus the cleaning solution on this unit was changed from detergent to 1,000ppm available chlorine cleaning /disinfection solution.

2004 Our actions appeared to have the desired effect. Rates of MRSA dropped to 0.08 per 100 admissions.

2005 Review at the end of 2004 revealed that the previous few years had seen a reduction in the numbers of MRSA cases identified at admission. It was agreed to increase screening on admission to include any patient in another hospital in the past month in order to capture those increasing numbers of patients discharged from hospitals to await later admission for surgery. This proved to be the correct decision as figures for MRSA identified on admission in 2005 soared to the highest the hospital had on record (see Figure 2 below).

Figure 2

2006–Present Problems around prompt identification and isolation of carriers on admission remains an identifiable weakness in the screening and isolation program. To be most effective, all those identified as “at-risk of MRSA” would need to be nursed in single rooms until their admission MRSA results were available.² Single-room availability simply does not stretch that far, even for our hospital. We have, however, decided to allocate single rooms to all direct transfers from other hospitals and nursing homes whenever possible. It remains to be seen if this will improve our figures for 2006.

Conclusion
The author recognizes that annual fluctuations in numbers of MRSA must be taken into account when reviewing figures. However, reviewing possible causes for fluctuations enabled us to update practice issues and maintain continuous quality improvement program.

The author concludes that in order to be effective, an active infection control program must incorporate education of staff, surveillance of MRSA infection, isolation of carriers, a treatment regime for all isolates, regardless of site, and a targeted screening program to detect MRSA.

However, the author has found that, in order to sustain a reduction in nosocomial MRSA, constant vigilance and monitoring of surveillance figures must be combined with constant review and analysis of the effectiveness of the infection control program and targeted changes to practice implemented.

References

1. Kluytmans JA et al. Nasal carriage of Staphyloccus as a major risk factor for wound infections after cardiac surgery. J Infect. Dis 1995;171:216-9.
2. SARI Infection Control Sub committee. The control of MRSA in Hospitals and the Community. HCPA 2006; 16-22.