Prioritising the prevention of medication handling errors.

OBJECTIVE: Medication errors are frequent in a hospital setting and often caused by inappropriate drug handling. Systematic strategies for their prevention however are still lacking. We developed and applied a classification model to categorise medication handling errors and defined the urgency of correction on the basis of these findings.
SETTING: Nurses on medical wards (including intensive and intermediate care units) of a 1,680-bed teaching hospital.
METHOD: In a prospective observational study we evaluated the prevalence of 20 predefined medication handling errors on the ward. In a concurrent questionnaire survey, we assessed the knowledge of the nurses on medication handling. The severity of errors observed in individual areas was scored considering prevalence, potential risk of an error, and the involved drug. These scores and the prevalence of corresponding knowledge deficits were used to define the urgency of preventive strategies according to a four-field decision matrix. MAIN OUTCOME MEASURE: Prevalence and potential risk of medication handling errors, corresponding knowledge deficits in nurses committing the errors, and priority of quality improvement.
RESULTS: In 1,376 observed processes 833 medication handling errors were detected. Errors concerning preparation (mean 0.88 errors per observed process [95% CI: 0.81-0.96], N = 645) were more frequent than administration errors (0.36 [0.32-0.41], N = 701, P < 0.001). Parenteral drugs (1.10 [1.00-1.19], N = 492) were more often involved in errors than enteral drugs (0.32 [0.28-0.36], N = 794, P < 0.001). Of the 833 observed medication errors 30.9% concerned processes of high risk, 19.0% of moderate risk, and 50.1% of low risk. Of these errors 11.4% were caused by critical dose drugs, 81.6% by uncomplicated drugs, and 6.9% by nutritional supplements or diluents without active ingredient. According to the decision matrix that also considered knowledge deficits two error types concerning enteral drugs (flaws in light protection and prescribing information) were given maximum priority for quality improvement. For parenteral drugs five errors (incompatibilities, flaws in hygiene, duration of administration, check for visible abnormalities, and again prescribing information) appeared most important.
CONCLUSION: We successfully applied a newly developed classification model to prioritise medication handling errors for prevention strategies.