Improving patient safety is always a key focus in the hospital setting, and pharmacists have been exploring a variety of strategies and technologies to achieve this goal. Automated dispensing machines—decentralized medication distribution systems that provide computer-controlled storage, dispensing, and tracking of medications—have been recommended as one potential mechanism to improve efficiency and patient safety, and they are now widely used in many hospitals.1 There is no doubt that these machines can enhance the efficiency of medication distribution, but their capacity to reduce medication errors is controversial and depends on many factors, including how users design and implement the systems.2 Still, we are confident in providing the following reasons and experiences to support our position that automated dispensing machines improve patient safety.
Before the implementation of unit-based automated dispensing machines in 1995, the hospitals within the University Health Network in Toronto, Ontario, relied heavily on manual distribution systems, including traditional floor stock and medication carts, which held a 24-h supply (or, at Princess Margaret Hospital, a 10-day supply) of patient-specific medications in individual patient cassettes. A floor stock system is flexible, but the pharmacy has little control over inventory. Although the 24-h unit-dose cart exchange offers tighter inventory control, it is often regarded as an inefficient drug distribution system.3 In addition to being labour-intensive, other major concerns with these carts include delays in delivery of the first dose, loss of doses, and “borrowing” of patients’ medications.4 In contrast, automated dispensing machines provide a good balance among security, accessibility, and inventory control of medications, which are all recognized as important characteristics of a safe medication distribution system.
Automated dispensing machines provide secure medication storage on patient care units, along with electronic tracking of the use of narcotics and other controlled drugs.2 Reports can be generated to help identify and prevent potential diversion. Automated dispensing machines save nursing time by eliminating the need for manual end-of-shift narcotic counts in patient care units. Before 2004, large quantities of floor stock were available in the operating rooms at Toronto General Hospital, with narcotics and other controlled drugs being stocked manually in a double-locked cabinet. This system was prone to many problems, including under- or over-stocking of inventory, missing or inaccurate drug charges, no tracking of drugs and drug waste, and complicated manual documentation procedures for narcotics and other controlled drugs. To improve efficiency and control of narcotics and other medications in the operating suite, a system of automated dispensing machines was implemented, in conjunction with a 24-h exchange program for anesthesia trays.5 This project began in early 2003 and was completed in May 2004. Every anesthetist has now completed the required training and is accountable for using this cabinet for the removal and return of narcotics and controlled drugs to be administered during surgery. The goal of maximizing patient safety has been achieved through the choice of automated dispensing machines with mini-drawers, which open only when a specific medication is selected and which limit access to the selected quantities.
Another clinical feature of automated dispensing machines is the capability to track and proactively monitor drug usage patterns. This is accomplished by setting up clinical indicators during removal of specified drugs. One example of this approach involved aprotinin, a medication that is administered by injection to reduce bleeding and to decrease the need for blood transfusions during complex surgery. This drug is expensive, and there are restrictions on its use; it was therefore deemed suitable for testing the use of clinical indicators. During the test period, physicians were asked to select the specific indication for use, by on-screen prompting, whenever they removed aprotinin from the automated dispensing machines. The reporting capabilities of the machines allowed pharmacy staff to regularly track and monitor the appropriateness of aprotinin use, and the results of tracking were reported back to the physicians. This process reduced inappropriate use by more than 50%. Similar processes for enhancing patient safety by enforcing appropriate utilization can be set up for any high-risk drug.