Medication errors: do they occur in isolation?

To cite: Franklin BD. BMJ Qual Saf Published Online First: [please include Day Month Year] doi:10.1136/ bmjqs-2014-002924 Medication error research typically focuses on just one stage of the medication use process: prescribing, transcribing, dispensing, administration or monitoring. Such simplification is required so that manageable boundaries can be set around the research, and to make it easier to specify error definitions, methods and denominators. However, this is clearly very simplistic, and from the patient’s perspective it is a somewhat arbitrary and meaningless distinction. In addition, many quantitative studies present the numbers of doses, drugs or patients with one or more errors, which makes it easy to miss the fact that multiple errors can occur together. While studies of adverse drug events (ADEs) typically include a wider range of sources of harm, some analyses include only the first ADE identified for each patient. Collectively, this means we may miss the opportunity to explore how multiple errors may occur together in the same patient. And yet detailed investigations into catastrophic medication errors typically reveal a whole concatenation of errors and failed defences, involving multiple stages of the medication use process. 2 We therefore need to better understand how errors are related across the whole medication process. A paper presented by Carayon et al explores this very issue in two US adult critical care units, shedding new light on the complexities surrounding medication use in the hospital setting. While the critical care setting is likely to be particularly complex, with patients prescribed high numbers of medications, particularly intravenously, the principles are likely to apply much more widely. Carayon et al took the novel approach of analysing errors both by group (where more than one error occurs for the same medication order at the same stage of the medication use process) and sequence (where errors in one stage of the medication use process were judged to have led to further errors in other stages). They identified medication errors and ADEs in 630 critical care admissions, with their main analysis focusing on the more serious errors: potential ADEs (medication errors which could have resulted in harm but did not) and preventable ADEs (medication errors which resulted in actual patient harm). There were 1145 potential ADEs and 38 preventable ADEs. Overall, most (84%) of these involved single medication errors, but 6% involved grouped errors and 10% sequential errors. Of the 145 grouped errors involved in 67 potential or preventable ADEs, almost all occurred at the ordering (prescribing) stage, where information on several elements of the same medication order was missing or incorrect. These are not discussed further in the paper, but such grouping might suggest the prescription of medication for which the prescriber had limited knowledge, was rushing, or was otherwise distracted. In contrast, the most common sequences involved an error in dispensing followed by an error in administration (usually omission of medication), or an error in transcription followed by an error in administration due to medication administration records being incorrect. Many other sequence combinations were also observed: the 121 potential and preventable ADEs caused by sequential errors involved a total of 264 errors and 21 different sequences. The majority of sequences culminated in an error at the administration stage but most began at ordering, transcription or dispensing. Staff responsible for administering medication are therefore ‘inheriting’ a wide range of errors from earlier stages of the medication use process. While no previous studies provide such a detailed description of grouped and sequential medication errors across the whole medication use process, reports from other countries also highlight how errors in one part of the process can lead to others downstream. Taxis et al identified medication administration errors EDITORIAL