Methodological validation of monitoring indicators of antibiotics use in hospitals.

BACKGROUND: For several years now, the French national recommendations have been trying to set up a surveillance system in hospitals to link data on antibiotic resistance and data on the use of antibiotics, particularly for certain 'micro-organism/antibiotic' pairs. The indicators recommended in the lastest newsletter of the Direction Générale de la Santé (French Public Health Department) for monitoring the consumption of antibiotics were the number of days of treatment or the number of defined daily doses (DDD), both (in)directly related to the number of days of hospitalisation and/or the number of patients hospitalised. OBJECTIVE: The aim of this study was to compare the actual number of days of treatment, which is an observed indicator, with two indicators calculated on the basis of the DDD and the DPD (daily prescribed dose), both in terms of feasibility of collection and the relevance of the information generated. MATERIALS AND METHODS: For several hospital care units, the 'length of exposure' to a given antibiotic was determined by four different indicators: two actual observed indicators [the patient's medical file (reference) and the named-patient based, computerised dispensing system from the central pharmacy] and two derived calculated indicators [obtained by dividing the number of grams prescribed by the DDD or by the DPD]. RESULTS: The average incidence density of antibiotic treatment (length of exposure per 1000 days of hospitalisation) obtained by the calculated indicators was higher than that obtained with the observed reference (+52% for the DDD and +33% for the DPD) but lower than that obtained with the second observed indicator (computerised system) (-10%). The differences were large and random (high variability depending on the hospital department, the antibiotic and the administration route; variations in both directions: actual length of treatment longer or shorter than the calculated length of treatment). CONCLUSION: The question which indicator should be chosen is inconclusive for the evaluation of the selection pressure exerted by an antibiotic. The two indicators proposed in the newsletter (observed indicator and calculated indicator) seem to be complementary for use in a regional or national network to monitor resistance and consumption of antibiotics. Each hospital should validate the indicators and define for itself which indicator is most appropriate for estimating the actual length of antibiotic exposure. This may imply different indicators for different units, antibiotics or even administration routes within one particular hospital setting. Once validated the hospital has a powerful tool generating data that can be linked to resistance data.

Observational study of potential risk factors of medication administration errors.

OBJECTIVE: Medication administration errors (MAEs) are the second most frequent type of medication errors, as has been shown in different studies in the literature. The aims of this observational study were to assess the rate and the potential clinical significance of MAEs and to determine the associated risk factors. DESIGN: In two departments, Geriatric Unit (GU) and Cardiovascular-Thoracic Surgery Unit (CTSU) of Besançon University Hospital (France), MAEs were identified using the undisguised observation technique and classified according to the definitions of the American Society of Health-System Pharmacists. Injectable administration, lack of nurses's standardized protocol for the preparation and administration of drugs, incomplete or illegible prescription and nurse's workload were analysed as potential risk factors of MAEs in multivariate logistic regression analysis. RESULTS: During a period of 20 days, opportunities for error concerning 56 patients and 78 MAEs (58 in CTSU and 26 in GU) were observed. The medication administration error rate was 14.9%. Dose errors were the most frequent (41%) errors, followed by wrong time (26%) and wrong rate errors (1996). No potential fatal errors were observed, 8 (10%) were estimated as potentially life-threatening, 20 (26%) potentially significant and 50 (64%) potentially minor. Nurse workload and incomplete or illegible prescriptions were two independent risk factors of MAEs. CONCLUSION: According to these data, the quality of the medication administration process needs to be optimized in hospitals in order to minimize the incidence of iatrogenic preventable diseases.

Relationship between spread of methicillin-resistant Staphylococcus aureus and antimicrobial use in a French university hospital.

The objective of our study was to determine whether antibiotic pressure in the units of a teaching hospital affects the acquisition of methicillin-resistant Staphylococcus aureus (MRSA), independently of the other collective risk factors previously shown to be involved (MRSA colonization pressure, type of hospitalization unit, and care workload). The average incidence of acquisition of MRSA during the 1-year study period was 0.31 cases per 1000 days of hospitalization, and the use of ineffective antimicrobials reached 504.54 daily defined doses (DDDs) per 1000 days of hospitalization. Univariate analysis showed that acquisition of MRSA was significantly correlated with the use of all antimicrobials, as well as correlated with the use of each class of antimicrobial and with colonization pressure. Multivariate analysis with a Poisson regression model showed that the use of antimicrobials was associated with the incidence of acquisition of MRSA, independently of the other variables studied, but it did not allow us to determine the hierarchy of the different antimicrobial classes with respect to the effect.

Clinical and molecular epidemiology of hospital Enterococcus faecalis isolates in eastern France.

OBJECTIVE: To report on the occurrence of Enterococcus faecalis hospital isolates obtained during 1 year in hospitals in the Franche-Comté region of France. METHODS: Clinical isolates of E. faecalis of different antibiotic susceptibility phenotypes from hospitalized patients were characterized by pulsed-field gel electrophoresis. Patients with positive cultures were investigated by three case-control studies to identify risk factors for colonization/infection. RESULTS: The crude incidence of colonization/infection was 2.37%, and 4-day and 7-day colonization rates after admission were 10.0% and 6.36%, respectively. The rates of high-level resistance to kanamycin (HLKR) and to gentamicin (HLGR) were 47.1% and 7.1%, respectively. No isolate was resistant to glycopeptides or produced beta-lactamase. The 209 hospital isolates obtained during the study yielded 98 major DNA patterns, of which two were major epidemic patterns including HLKR isolates. No single factor was significantly associated with colonization/infection by HLKR isolates. The length of hospitalization before isolation was associated with colonization by HLGR isolates. CONCLUSIONS: The isolation frequency of E. faecalis strains with acquired resistance to aminoglycoside antibiotics, and the wide dissemination of resistant strains with characteristics that allow them to persist and spread, argue for further large prospective surveys of clinical isolates of E. faecalis in hospitals.