Introduction

In countries where there is unrestricted sale “over the counter" of antibiotics, uncontrolled misuse of antibiotics is responsible for a general pool of resistant strains in the microbial population. Sales of antibiotics should be restricted to medical prescription only.

Within hospitals, the unnecessary use or overuse of antibiotics encourages the selection and proliferation of resistant and multiply resistant strains of bacteria. Once selected, resistant strains are favoured by antibiotic usage and spread by cross-infection. Where resistance is encoded on transmissible plasmids, resistance can also spread between bacterial species.

There is thus a link between antibiotic use (or abuse) and the emergence of antibiotic resistant bacteria causing hospital-acquired infections. It is not possible to completely eliminate this evolutionary phenomenon, but it can be slowed or modified by prudent antibiotic use. This requires the inclusion of an antibiotic policy in the infection control programme.

Why is an antibiotic policy necessary?

An antibiotic policy will:

• improve patient care by promoting the best practice in antibiotic prophylaxis and therapy,
• make better use of resources by using cheaper drugs where possible
• retard the emergence and spread of multiple antibiotic-resistant bacteria.
• improve education of junior doctors by providing guidelines for appropriate therapy
• eliminate the use of unnecessary or ineffective antibiotics and restrict the use of expensive or unnecessarily powerful ones

Formation of a Hospital Antibiotic Committee

The medical director and/or hospital manager should ensure that the hospital plan for prevention and control of nosocomial infection includes an official committee that has responsibility for the formulation and supervision of an antibiotic policy. This might be a subcommittee of the hospital Drugs and Therapeutics Committee or of the Infection Control Committee. The Antibiotic Committee should have the support of the Medical Director and the authority to ensure that its policies are implemented throughout the hospital.

Function of the antibiotic committee

The main tasks of an antibiotic committee are the following:

• to consult widely with the clinical staff to get agreement on antibiotic usage in different specialities
• to then establish an antibiotic formulary, which may prevent the use of some drugs and restrict the use of others
• to formulate guidelines for antibiotic prescribing, including indications for prophylaxis and therapy of infection, the optimum dosages, timings and duration of therapy and policies for minimising the risks of toxicity
• to review the appropriateness of antibiotic use and the emergence of antimicrobial resistance and provide feedback on this to clinicians
• to be responsible for education and dissemination of information
• to work closely with the Infection Control Team and the Microbiology Department

The Key Members of the Antibiotic Committee

Membership of an antibiotic committee may vary according to local conditions and needs. The committee should be responsible for producing general guidelines and policies for the health care areas after wide consultation with the users.

If possible, the following key persons should be included in the committee:

• The Pharmacist who will report back to the Antibiotic Committee at each meeting on drug utilisation and cost.
• The Microbiologist who will report on antibiotic susceptibility patterns of bacteria isolated from major infections.
• Clinical doctors and nurses responsible for direct patient care who provide a link between clinical practice and the Antibiotic Committee.
• Manger(s) who will ensure the resources are available for implementation of the antibiotic policy.
• Reciprocal Membership between the Infection Control Committee and the Drugs Committee should be ensured.

Other members can be co-opted as necessary.

The antibiotic committee will have to make rational choices amongst "equivalent drugs" and classes of drugs in order to select the least expensive, most effective agents. Cost should determine the selection, when microbiological, pharmacological, and other relevant properties are similar.

Guidelines

A major task of the Antibiotic Committee will be to establish guidelines for antibiotic use. This will lead to production of a formulary that restricts agents available to the minimum number needed for most effective therapy.

The guidelines should

• be drawn up after wide consultation and agreement in the hospital
• be simple, clear and short, and ideally published in a booklet small enough to be carried in a pocket
• be provided to all newly appointed doctors and nurses and readily available in the hospital, for example, available on wards
• contain guidance on antibiotic prophylaxis (e.g. in surgery with details of timing, route, dosage and frequency)
• contain guidance on the choice of antibiotics for empirical and targeted therapy of major infections
• indicate first and second line therapy for common infections (might limit the use of certain second line drugs to consultant prescription only)

Good Practices

• Consider whether or not the patient actually requires an antibiotic.
• Avoid treating colonised patients who are not actually infected.
• In general do not change antibiotic therapy if the clinical condition is improving.
• If there is no clinical response within 72 hours, the clinical diagnosis, the choice of antibiotic and/or the possibility of a secondary infection should be reconsidered.
• Give the antibiotic for the minimum length of time that is effective.
• Review the duration of antibiotic therapy after 5 days.
• Consider the use of pharmacy ‘stop' policies, where drugs are written up for a specified period and are then only continued if a new prescription is issued.
• For surgical prophylaxis start the antibiotic with the induction of anaesthesia and continue for a maximum of 24 hours only.

Contribution from the Microbiology Laboratory

The microbiology laboratory contributes in several ways towards the daily clinical management of infection.

The clinician should receive reports of antibiotic susceptibility based on the drugs available in the agreed formulary. The testing should be performed with a limited number of antibiotics selected to optimise patient care and cost effectiveness. The number of antibiotics reported might be limited in order to encourage better prescribing (e.g. augmentin need not be reported if the organism is sensitive to ampicillin). The report should also indicate where organisms are invariably resistant (e.g., methicillin-resistant S. aureus are resistant to all beta-lactams).

The Antibiotic Committee and the Infection Control Committee should receive regular updates on antibiotic susceptibility of bacterial isolates from the local area. This will assist the Committees in producing effective guidance for the local patient population. The laboratory should also alert the Committees to the emergence of widespread resistance to certain agents so that the inclusion of those agents in the guidelines can be reviewed.

When no local microbiology laboratory exists, antibiotic policy should be based upon a basic formulary, if possible established after consultation with regional or national groups. When resources for microbiology are scarce, priority should be given to examination of samples from nosocomial, life-threatening cases, or arrangements should be made for microbiology tests with a referral hospital. Culturing of the environment or screening of staff should be discouraged and only done after authorisation by the Infection Control Team.

Education

An effective antibiotic policy also provides and ensures education on the use of antibiotics at undergraduate and postgraduate level for medical and nursing staff.

The educational programme should teach how to critically evaluate and assess new drugs and provide education on the use and miss-use of antibiotics to hospital staff and practising physicians. This will reduce inappropriate prescribing. The programme will instruct in correct dosage, route and frequency from the point of view of cost effectiveness, and provide information to prescribers on the impact of their decisions on both economics and bacterial ecology.

Minimal requirements

• List of available antibiotics agreed by all clinicians, indicating dosages, routes of administration and toxicities.
• Guidelines for therapy and prophylaxis.
• A regimen selection algorithm also might be included in an antibiotic policy.