Methicillin Resistant Staphylococcus Aureus (MRSA) is now an everyday problem within healthcare organisations including those in the community. For Infection Control teams it can be their biggest challenge, particularly those in hospital, as it remains a significant cause of hospital - acquired infection. This article will describe MRSA, its microbiology and epidemiology, and how within the perioperative environment, practitioners can adopt evidence based practices to minimise and prevent the spread of MRSA to patients and colleagues. The article will also examine the wide variations in incidence within areas of Europe.

What is MRSA?
S. Aureus is a common pathogenic commensal bacterium found in warm, moist areas of the body, particularly the nose, axilla and perineum. Approximately 30% of the population are colonised with the bacterium – that is they carry S. Aureus but it does not cause them harm and they do not require treatment. However, within the hospital environment this means that potentially both patients and staff can act as a reservoir and source for the spread of infection to susceptible individuals (1,2).

S. Aureus causes a range of infections from superficial abscesses and boils to the more serious infections of osteomyelitis, septicaemia and pneumonia. MRSA causes the same types of infection and again people can be colonised with the bacterium, in some cases even the more sensitive strains of S. Aureus have been replaced by MRSA. S. Aureus is a gram-positive bacterium with a thick cell wall able to adapt to the presence of antibiotics and develop resistance by infiltrating the antibiotic molecule and disrupting its structure. Certain strains of S. Aureus became resistant to penicillin and an alternative antibiotic was found - methicillin.

However shortly after its introduction in 1960 resistant strains were reported and incidences increased with many serious outbreaks in hospitals (2). Methicillin is now used as a screening process in the laboratory for sensitivity testing and hence the title MRSA. As new antibiotics appeared then incidences from the 1970’s until the 1980’s decreased. Gradually MRSA became more resistant and reports of outbreaks increased, with epidemic strains (EMRSA) being reported in London in the mid 1980’s. (EMRSA 3 is often isolated from pressure sores; EMRSA 15 is often associated with pulmonary infections) (3,2). MRSA is now endemic in many hospitals - that is MRSA regularly occurs (is compulsorily reported to the Public Health Laboratory Service (PHLS)) and shows little variation in its incidence.

Why is it dangerous?
MRSA can only be treated with the glycopeptide group of antibiotics such as vancomycin, which are expensive, can only be given intravenously and are associated with renal impairment (4). In 2002 the latest figures from the PHLS revealed that MRSA infection rates have reached a plateau but that new strains of vancomycin resistant S. Aureus (VRSA) are emerging. The first known case of VRSA was reported in Japan in 1997 and although still rare in incidence it must not be ignored (3). The PHLS reported the first case of intermediate resistance to vancomycin in England and Wales in 2002. This development is potentially hazardous with disastrous consequences as it reduces the treatment options for those patients with MRSA (5).

It has been identified that the implications for a patient who contracts MRSA in hospital include : extended length of stay, loss of earnings, scarring, pain, anxiety and depression (1,6). For the hospital staff the effects include increased workload, disruption to ward routine and may even result in temporary ward closures. The financial cost to both the patient and organisation cannot be measured. However managing and controlling MRSA outbreaks can have less of a financial impact than if the outbreak is uncontrolled.

Costs in excess of £40,000 at Kettering during an outbreak for the provision of an isolation ward have been cited (7), in London £13,000 for screening, antibiotics and clothing but did not include hotel costs and during an large outbreak in Madrid costs exceeded £700,000 due to the cost of antibiotics, extended length of stay for the patients and the treatment for wound infections.

How does it get there?
The primary mode of transmission of MRSA is by direct contact, usually with another person’s hands. MRSA has also been isolated from people’s hands after touching contaminated material or equipment (8).

MRSA may also be released in to the atmosphere on skin squames and fibres from clothing and carried as dust particles. About 300 million dead skin squames are shed daily, with as many as 10,000 per minute shed during excessive movement, of which 10% may carry micro-organisms (2). Therefore it is essential that all equipment and inanimate objects are kept clean and free from dust.

MRSA is a common isolated organism in postoperative wound infections, but can also be isolated from intravenous catheter tips, chest drains and burn wounds. MRSA was identified as the cause of surgical site infection in almost 25% of all wounds examined, and the commonest staphylococci in large bowel surgery, vascular and limb surgery, open reduction of long bone fracture and hepato-biliary surgery (6). The majority of wound infections arise from the patients’ own skin flora (endogenous) although some come from the Operating Theatre and its staff (9).

How do we control it?
It has been advocated that an active programme of controlling MRSA and its spread is essential to reducing the impact on the organisation as well as the financial burden (7). In their view not doing anything is not an option. In the Netherlands and Western Australia active and aggressive screening and infection control policy (search and destroy) has led to improvements and containment.

It has been shown that although the number of cases of serious S. Aureus infections reported in the Netherlands, also Sweden, Denmark and Iceland has increased this is still low in comparison to the rest of Europe- 3% as opposed to 46% in the United Kingdom, (the highest in a recent European survey) closely followed by Israel and Greece (10,15).

The policy in Northern Europe includes the selective and prudent use of antibiotics in the management of many other diseases. It has been suggested that doctors should question the need for antibiotics and monitor the length of time the patient is on them and their effectiveness (3). It has also been identified that in Southern Europe the prevalence of MRSA within healthcare organisations is very high and that the attitude is one of inevitability and that prevention is inappropriate (10).

Each healthcare organisation must have a policy for the management of patient(s) infected with MRSA. The primary aim of any infection control policy is to prevent the acquisition and spread of MRSA by patients and staff (7). Guidelines were produced to address the problems encountered with the wide and varied management of these patients in different organisations. They recommended four categories of risk.

Risk Assessment classifies MRSA cases into low, medium or high in an attempt to guide nurses on how to manage these patients (1). High risk areas - those with the potential to develop serious infection as a result of acquiring MRSA include intensive care, transplant units, orthopaedic and trauma wards, burns units and neonatal units. The guidelines suggest actions to be taken in organisations where MRSA is endemic and how to effectively utilise resources and facilities (7,11).

Screening of all patients for MRSA as part of the pre-operative assessment process may be impractical and costly, but for selected groups may be beneficial. For the patient undergoing major joint surgery, screening for MRSA prior to surgery will allow all precautions to be taken to prevent prolonged hospital stay, breakdown of the wound, the potential for infection of the joint and breakdown of the prosthesis (7,9,11).

Controversy continues about how to deal with MRSA and despite advocating a flexible approach in their guidelines many nurses still insist that patients infected with MRSA should be isolated (1). It has been argued that with a limited number of side rooms available and that precautions taken should reflect what we are going to do to the patient and not by what we know of their infection status (4). The RCN (11) support this idea and state that we should assess the patient’s individual risk to others and the risk to themselves by the presence of invasive devices for example.

Within the perioperative environment the guidelines, limited as they are, recommend that if at all possible MRSA should be eliminated prior to surgery. However, this is not always achievable and so it was suggested that vancomycin or teicoplanin are given prophylactically, patients are recovered in the operating theatre or isolated area to avoid possible contamination of the usual area, and that all theatre surfaces in contact with or near the patient should be disinfected before the next patient (7).

Implementing contact precautions by isolating patients within the Operating Theatre Department will involve moving them directly in to the theatre itself, bypassing any holding area, and post-operatively nursing them in a designated isolation area or nursing them in theatre itself. The practices in local hospitals were reviewed for the management of MRSA infected patients through the perioperative environment and it was concluded that there is a need for clearer guidance and evidence based recommendations to ensure high standards of care are given (9).

Following the review by Brown & Cumberland (9), the practices outlined below have now been suggested:

1. MRSA positive patients are operated on at the end of the list. Such patients are likely to disperse micro-organisms into the atmosphere and potentially are a risk to other patients (12). However operating lists can be delayed and the MRSA positive patient may not receive their surgery on that designated day.

2. All non-essential equipment should be removed to prevent contamination for subsequent patients.

3. Minimal staff should be present in the theatre to prevent cross-contamination between staff and patients.

4. The Operating Theatre and associated equipment should be cleaned with a hypochlorite solution once the wound is closed and the theatre rested between patients. The transmission of infection between successive patients is probably airborne on items of equipment or surfaces that have been in contact with the infected patient (12). MRSA can survive in dry conditions and for some considerable time so it is essential that the appropriate cleaning solution be used (13).

5. If no further surgery is to follow then theatre personnel need only change their scrub suits and theatre greens.

6. Patients will be recovered within the Operating Theatre.

The single most effective method of preventing and controlling the spread of MRSA is by the effective decontamination of hands after every patient episode of contact. It was identified that hand hygiene is not performed adequately nor often enough (frequency and quality are poor) but recognised that facilities may be insufficient, with ineffective hand solutions, no mixer taps and paper towels which are harsh and abrasive (4,13).

The National Audit Office (6) agree with these findings but showed through studies that decontamination of hands between every patient can reduce hospital infection rates. Practitioners should implement strict hand washing practices as recommended by the National Evidence-based Guidelines for Preventing Healthcare associated Infections (14). Hand washing should be carried out all times following any patient contact and with all patients. Hands should also be washed following the removal of protective clothing, before handling invasive devices and after handling body fluids and items contaminated with body fluids (11).

In Conclusion
As practitioners we should question our own knowledge and practices for the management of the patient with MRSA. Does the Department have an Infection Control Policy and were theatre staff involved in writing it? One could question theatre practitioner’s ability to wash their hands as we are excellent at knowing how to "scrub up" but between patients, after any patient contact do we always wash our hands? And what do we wash them with? Excessive use of chlorhexidine or iodine solutions could be detrimental to the condition of the hands but do the scrub sinks or sluices have soap dispensers?

MRSA clearly warrants the name "super bug" and we should not be complacent. As theatre practitioners we have an important role to play in preventing the spread of MRSA not only to patients but also to colleagues. Being accountable means that through our actions or omissions we do the patient no harm.

References


1. Makoni T, MRSA : Risk Assessment and Flexible Management. Nursing Standard, 2002; 16 (28): 39-41.
2. Wilson J, Infection Control in Clinical Practice 2nd Edition, 2001; Edinburgh. Balliere Tindall.
3. Taylor D, NT Monograph- Antibiotic Resistance : A Concern For All. Nursing Times Clinical Monographs, 1999; No 16.
4. Storr J, MRSA 2000. Nursing Times Plus, 2000; 96 (10 ): 3-4.
5. Kenny C, Hospital Bacteria Develops New Resistance to Drug. Nursing Times, 2002; 98 (41): 5.
6. National Audit Office, The Management and Control of Hospital Acquired Infection in Acute NHS Trusts in England London. The Stationery Office, 2000.
7. Ayliffe, Prof G.A et Al, Working Party Report - Revised Guidelines for the Control Of Methicillin-resistant Staphylococcus Aureus Infection in Hospitals. Journal of Hospital Infection, 1998; 39: 253-290.
8. Fogg D, Clinical Issues. AORN 2002; 76 (1): 175.
9. Brown M & Cumberland Dr. N, Is It Time For Change? - Theatre Protocols for Methicillin-resistant Staphylococcus Aureus (MRSA) Positive Patients. British Journal of Infection Control, 2000; 1 (4): 13-14.
10. Van Belkum A. & Verbrugh H, 40 Years of Methicillin Resistant Staphylococcus Aureus: MRSA Is Here to Stay - But It Can Be Controlled. British Medical Journal, 2001; 323 (7314): 644-645.
11. Royal College of Nursing Methicillin Resistant Staphylococcus Aureus (MRSA) - Guidance for Nurses. London. RCN, 2000.
12. The Royal College of Anaesthetists Infection Control in Anaesthesia London. Royal College of Anaesthetists, 2002.
13. Curran ET, MRSA: Monitoring Quality. British Journal of Infection Control, 2002; 2 (1): 20-23.
14. Pratt. Prof. RJ et Al, The Epic Project: Developing National Evidence-based Guidelines for Preventing Healthcare Associated Infections. The Journal of Hospital Infection, 2001; 47 (supplement).
15. White C, UK Has Worst MRSA Rates. Nursing Times, 2002; 98 (12): 8.