Strategies to prevent the transmission of multi-resistant organisms

Previous infection control questions in the SAQs have consisted of the following:

• Question 20 from the first paper of 2020
• Question 12 from the first paper of 2016
• Question 7 from the first paper of 2011

Question 7 from the first paper of 2011 puts the candidate in the position of an ICU director, confronted with the reality that their unit is a disgusting toilet full of MRSA. The candidate is then invited to produce a program which will reduce the incidence of MRO transmission. The question was done poorly (only 25% of the candidates passed) presumably because this topic is boring, and nobody wanted to study it.

In order to counteract this phenomenon, the trainees need a brief point-form set of evidence-based guidelines which they can memorise and dutifully regurgitate during the viva. Given the non-trivial value of infection control policies, the retention of this material can only have a positive effect in the long term, as it seeps back out of the unconscious and into daily practice.

Such brief point-form summaries are nowhere to be found. For instance, Oh's Manual contains a whole chapter on nosocomial infections (Ch.70 by Hatcher and Dhillon), but the section on infection control spans only two or three paragraphs. Clearly, a better resource is needed for the time-poor trainee.

If one were to limit oneself to reading only one paper on this topic, the SHEA guidelines statement from 2003 should be that paper. The brief point-form summary offered below has been cobbled together from the SHEA guidelines. For general infection control information, Eggimann and Pittet's 2003 article is satisfactory. If one wanted a brief overview instead of detailed data, one could do worse than this brief book chapter by Dhillon Shah and Rimawi. If, however, one were insane, one could peruse the CDC guidelines database, or the 54-page NSW Health Infection Control Policy Directive for a more local flavour.

Modes of transmission of MROs

• Health worker hands
  • Contamination of hands and gloves by contact with the colonised patient, or with surfaces within the colonised patient's room.
• Health worker clothes
  • Contamination of clothes by contact with the patient, patient's bed or surfaces in the patient's room
• Health care instruments
  • Use of the same instruments between several patients, with inadequate sterilisation
• Health care environment
  • Contamination of hand-washing faucet handles, common surfaces eg. computer keyboards, furniture, etc.

Prevention of multi-resistant organism transmisison

Active surveillance cultures

• Identifies the "reservoir" for spread
• Allows precautions to be cost-effectively focused on the reservoir.
• The health care workers themselves may become colonised reservoirs.
• Performed on all patients, on admission, and then peridoically (eg. weekly).
• In facilities found to have a high prevalence on initial sampling, a facility-wide culture survey is indicated.

Contact precautions

• Hand hygiene
  • Soap and water for visibly contaminated hands
  • Alcohol-based rub for routine pre-and-post-contact hygiene
  • Monitoring of compliance should be performed
• Disposable gloves
• Disposable gowns
• Patients colonised by the same MRO may be cohorted together.
• Contaminated areas should be identified by obvious cautonary signs

Eradication of existing colonies

• Decontamination ("decolonisation") of MRSA/VRE patients
• Decontamination of colonised health care workers
• Environmental disinfection
• Routine disinfection of equipment between patient contacts
• Wherever possible, individualised equipment for every patient

Prevention of MRO emergence

This specific issue became the subject of Question 11 from the first paper of 2011.

Prevent emergence of antibiotic resistance:

• Limit use of broad-spectrum agents
• Restrictions on the use of last-line antibiotics
• Limit use of multiple antibiotics
• Surveillance and restriction on the use of prolonged or inappropriate antibiotic courses
• Use narrow-spectrum agents whenever sensitivities are available
• Rationalise duration of antibiotics to prevent over-long courses
• Invitation to infectious diseases physicians to take part in antibiotic decisionmaking
• Antibiotic class cycling

According to a 2011 review, antimicrobial stewardship interventions beyond 6 months were associated with reductions in antimicrobial resistance rates, which suggests that the above strategies can be rapidly effective.

Organisation of infection control processes

According to the college answer for Question 12 from the first paper of 2016, these should take the form of Unit Policies and "MUST be instituted, championed and audited". The words "championed and audited" sound a lot like a memorably spoutable key phrase, and may be associated with increased marks. Another such key phrase to trigger a mark-gasm is probably "bundles of care", such as an Education Bundle, Prevention Bundle and Management Bundle. The college seem to love bundles.

Thus:

Organisation

• Infection control specialty team, composed of ICU specialists, infectious diseases specialists, senior nursing staff, laboratory staff and administration staff.
• Allocated resources to MRO surveillance, compliance monitoring and education
• "Champions" - staff allocated to promote the existing policies and monitor adherence

Education

• "Widespread campaign", as recommended by the SAQ model answer
• Awareness-rasing posters
• Lunchtime meetings
• Promulgated reading material
• Education bundle as a part of mandatory employee training

Data collection and audit

• Data collection and MRO colonisation record
  • Records of MRO results allow colonised patients to be identified early
• Regular review of collected information, resistance and transmission patterns
• Regular audit of the efficacy of implemented strategies
• Regular comparison of policies to those of peer hospitals
• Regular reevaluation and amendment of infection control policies