Decentralized automated dispensing devices: systematic review of clinical and economic impacts in hospitals

Technologies have been developed over the past 20 years to automate the stages of drug distribution in hospitals, including ordering, dispensing, delivery, and administration of medications, in attempts to decrease medication error rates. Decentralized automated dispensing devices (ADDs) represent one such technology that is being adopted by hospitals across Canada, but the touted benefits, in terms of improved patient safety and cost savings, are increasingly being questioned.

To summarize and evaluate the existing literature reporting the clinical and economic impacts of using decentralized ADDs in hospitals.

A literature search was conducted in MEDLINE, Embase, and all evidence-based medicine databases for the years 1992 to 2012 to identify English-language articles reporting on the use of ADDs in hospital wards.

All randomized controlled trials, observational studies, before-and-after studies, time series analyses, cost-effectiveness and cost-benefit analyses, and review articles were considered for inclusion. Studies evaluating pharmacy-based ADDs, such as bar code-based medication dispensing carousels, automated dispensing shelves, and combinations of various dispensing modalities, were excluded.

Of 175 studies initially identified, 8 were retained for evidence synthesis. It appears that ADDs were effective in reducing medication storage errors and the time that nurses spent taking inventory of narcotics and controlled substances. There was no definitive evidence that using ADDs increased the time that nurses or pharmacists spent with patients, reduced medication errors resulting in patient harm, or reduced costs in Canadian hospitals. However, pharmacy technicians spent more time stocking the machines.

ADDs have limited potential to decrease medication errors and increase efficiencies, but their impact is highly institution-specific, and use of this technology requires proper integration into an institution's medication distribution process. Before deploying this technology, it is recommended that Canadian hospitals carefully examine their current systems and the benefits they hope to gain with the changes.