Brian Peters, PharmD, MS Director of Pharmacy Community Hospital North Indianapolis, IN

Introduction

Numerous articles have been published on the error-reduction potential and operational efficiency gains of central pharmacy automation.^1,2 Recognition of the potential safety gains has led to increased adoption of central pharmacy automation over the past decade, with at least one source reporting current usage at 10.2% of hospitals surveyed. This is up from 7.8% reported in 2002, and more than double the 1999 rate of 4.5%.³

One of the more contemporary entrants into this market segment is the automated pharmacy carousel system (APCS). The APCS is a 21st-century rendition of carousel-based medication storage that dates back to the 1970s. Unlike carousels from that era, however, modern APCS installations are partially or fully integrated with other pharmacy technologies (unit-based automated dispensing machines [ADMs], pharmacy information systems, wholesaler Web sites, etc).

The purpose of this article is to describe the installation, setup and use of an APCS in a 400-bed community hospital. Although my experience is limited to only one APCS vendor, the information presented should be applicable to any APCS.

Hospital Background

Community Health Network is a five-hospital system located in Indianapolis. With nearly 1,000 total beds, Community Health Network is the largest nonacademic hospital system in the metropolitan Indianapolis area. Community Hospital North (CHN) is the largest hospital in the system, with more than 400 beds providing medical, surgical, intensive/progressive care, maternity, neonatal, pediatric and behavioral care treatment to residents of the northeastern portion of metropolitan Indianapolis.

In late 2006, vendor selection for central pharmacy automation at CHN was completed when Talyst was selected. The implementation process began in early 2007. Although the implementation consisted of numerous components (carousels, software, automated packaging system, bar-code labelers), this article focuses specifically on implementation of the APCS.

Pharmacy Layout

CHN had the distinct advantage of installing the APCS in conjunction with a complete redesign and expansion of the existing inpatient pharmacy space, thus allowing for strategic placement of the carousels within the pharmacy to facilitate optimal product flow and staff efficiency. Key factors to consider when choosing a location for an APCS include proximity to the medication receiving area, as well as to the entrance/egress doors used by technicians. Secondary considerations include accessibility of the carousels for service, integration with medication storage areas other than the carousel (controlled substance cabinets, refrigerated storage, etc), and availability of sufficient counter space for receiving/dispensing activities. As some carousel pieces are quite large, vendors also will conduct an assessment of the physical space to ensure the presence of a navigable route from the loading dock to the pharmacy, adequate load-carrying capacity of the floor structure and sufficient overhead clearance.

Bar-Code Association

One of the most important tasks, and one of the first that must be completed during initial carousel setup, is association of medications and their corresponding bar codes. This association serves as the foundation for the entire system and must be completed in a timely and accurate manner. Because of the potential risk and liability involved, CHN delegated this responsibility to a small number of specially trained pharmacists. These pharmacists were selected for training based on their extensive knowledge of the hospital’s formulary, which helped to ensure the efficiency and accuracy of the process.

During bar-code association, every attempt should be made to identify and scan bar codes on all in-stock generic products. This will help to ensure the implementation proceeds smoothly by reducing the number of medications not recognized by the software.

Products generally are received into the APCS in manufacturer packs (i.e., cartons of 25), but most commonly are removed as individual doses. To facilitate this workflow, the hospital took the additional step of scanning not only the outer packaging of products, but also the bar code on each individual dose pack. This extra step also provided the hospital with a very robust bar-code database for use in subsequent implementation of bar-code medication charting.

Balancing Multiple Carousels

Many institutions will find it necessary to install multiple carousels (CHN decided on two 12-foot units). When multiple carousels are used, the most efficient plan is to equally divide the most commonly dispensed medications between the carousels. To accomplish this task, CHN obtained a dispensing report from its pharmacy information system and ranked the data in descending order of use. The 200 most frequently used medications were then equally divided between the two carousels (the most frequently used medications went into carousel 1, the next into carousel 2, etc.).

When performing this balancing process, be sure to exclude any controlled substances that will not be stored in the carousels. (See below for more information on considerations for storage of controlled substances.) Also be sure to take into account any storage areas that may be operated in conjunction with a carousel location, as this could influence the medications included in your velocity assessment.

Medication Location Within Carousels

In addition to the frequency of use, there are a number of other factors that should be considered when determining the physical location of medications within the APCS. One of the biggest advantages of carousel storage is the ability to dispense with alphabetical storage of medications. Much has been published regarding the potential for medication error when products with similar names (either in spelling or pronunciation) are located in close proximity.^4-6 Thus, staff assigned to load the carousels should have a copy of the facility’s “look-alike/sound-alike” (LASA) medication list and should reference it throughout the loading process. In addition to physically separating medications on the LASA list, every effort also should be made to segregate different strengths of the same product.

Another consideration when loading inventory into the carousels is segregation of specific medication types. When it is necessary to segregate by route of administration, extra caution should be exercised to avoid placing LASA medications next to one another. Increased grouping of medications based on route of administration makes this exponentially more difficult. If storage by route of administration is a state requirement, it may be prudent to petition your board of pharmacy for an exemption. An excellent case can be made that this type of storage segregation is no longer a necessity and negates many of the positive benefits of the APCS.

A second method of segregation is based on the cytotoxicity of the medications. There are advantages to segregating cytotoxic medications, including the ability to semi-automate the auxiliary labeling processes that many institutions do for these items. A simple act like putting the roll of cytotoxic stickers on the shelf/shelves where these medications are stored can serve as a “just in time” reminder to staff and improve labeling compliance.

Before loading the carousel, it also is important to decide what items (if any) will not be loaded into it. Potential “do not load” items include:

• Oral and parenteral cytotoxic medications in liquid form (due to spill risk)
• Controlled substances (due to regulatory/perpetual inventory concerns)
• Large, bulky items (may waste too much valuable carousel space)
• Extremely heavy items (check the load-bearing ability of shelves if in doubt)

Loading Carousels

Regardless of the approach taken, physically placing medications into the carousel is a time-consuming and challenging process. There probably is no single best approach; however, several potential options are discussed below to help guide the decision-making process.

Duplicate inventory method. In this approach, new drug stock is purchased to fill the carousel while the existing inventory is used to provide care to patients.

Advantages: minimizes disruption to existing operations; ensures full carousels at the time of conversion to APCS dispensing; ensures individual and bulk packages are available for bar-code association.

Disadvantages: significant increase in on-hand inventory that must be carefully managed and budgeted; drugs loaded in the carousel may reflect only the most recently purchased generic equivalents for a particular product; there may not be sufficient space to move the static shelf inventory into the carousel after conversion, resulting in a prolonged transition period.

50% Method. The 50% method involves allocating roughly half of the existing inventory to the carousel, while the remaining items stay on the shelves to support ongoing operations. On conversion day, the remaining inventory is loaded into the carousels as time allows, with a target completion of 48 to 72 hours.

Advantages: eliminates budgetary impact; carousels can be fully used at time of conversion.

Disadvantages: must manually override and correct wholesaler orders so replacement inventory is not ordered prematurely; potential for insufficient quantities of high-velocity items in the old static shelves and in the APCS; very difficult to find the time to relocate remaining inventory in the midst of this major workflow change.

Hybrid method. The hybrid method combines the above options. The duplicate inventory method is used for high-velocity/low-cost inventory items, whereas the 50% method is used for low-velocity/high-cost items. This approach minimizes the disadvantages of the two options, while maximizing their benefits.

Divide and conquer method. In this approach, the inventory is divided into more manageable segments (i.e., 200 inventory lines). During periods when carousel use is low, segments of 200 medications are transferred from static shelving to the APCS. At the time of the next batch or cabinet fill, technicians will pick from both the static shelving items and the APCS. Over the course of a few days, the entire inventory is loaded into the APCS and picking from the static shelves ceases.

Advantages: no extra inventory required; stockouts in the old and new storage locations are minimized; the wholesaler order generated by the APCS can be used without significant review or modification; staff can acclimate to the APCS in a more controlled manner.

Disadvantages: geographic location of the static shelves in relation to the carousels may decrease productivity; near the end of the process, it will become more difficult to find APCS “downtime” during which the next segment of 200 medications can be transferred

CHN employed the 50% method; however, it took a number of days to move the remaining static shelf inventory into the carousels. In retrospect, given the physical proximity of the hospital’s two inventory locations, the divide and conquer approach would have been ideal.

Stacking Versus Queuing

Numerous pharmacy operations are impacted by installation of the APCS. They include order placement; order processing/shelving; ADM restocking; cart/batch fill; first dose dispensing; physical inventory; retrieval of medications for restocking carts/kits/trays; and retrieval of medications for stocking in remote pharmacy locations (satellites, IV room, remote facilities).

In a traditional pharmacy, much of this work can be done simultaneously with minimal difficulty (a stacked work approach; Figure 1). Installation of carousels requires careful redesign of these tasks into a more sequential pattern (Figure 2). This process ideally should begin before the carousel goes live, but that may not be possible due to limitations with the existing pharmacy design and processes.

The need for sequential workflow can be minimized through three initiatives. First, workflow should be designed to minimize the amount of time spent at the carousel. For example, verification of bar-code recognition should be performed in the inventory receiving/breakdown area and not at the carousel. Second, software configuration should provide flexible, automated management of each of the pharmacy operations listed above. By assigning appropriate priorities to different transaction types, delays in patient care can be minimized and efficiencies maximized. Finally, larger facilities may want to consider purchasing multiple carousels to handle different functions.

Conclusion

Implementation of an APCS touches nearly every aspect of pharmacy operations. Such significant change is unlikely to proceed without some degree of difficulty. However, given the potential safety and efficiency benefits of an APCS, I believe that the difficulties and challenges are worthwhile.

The author would like to thank the pharmacy staff of Community Hospital North for their patience and support during this project. The impact on pharmacy operations was significant and would not have been successful without the buy-in and assistance of the entire staff. Also, special thanks to Jennifer Mullen, who at the time of our carousel installation was an administrative pharmacy resident with Community Health Network. Her efforts were also critical to the success of this project.

References

1. Poon EG, Cina JL, Churchill W, et al. Medication dispensing errors and potential adverse drug events before and after implementing bar code technology in the pharmacy. Ann Intern Med. 2006;145:426-434.
2. Oswald S, Caldwell R. Dispensing error rate after implementation of an automated pharmacy carousel system. Am J Health Syst Pharm. 2007;64:1427-1431.
3. Pedersen CA, Schneider PJ, Scheckelhoff DJ. ASHP national survey of pharmacy practice in hospital settings: Dispensing and administration—2008. Am J Health Syst Pharm. 2009;66:926-946.
4. Survey on LASA drug name pairs: who knows what’s on your list and the best way to prevent mix-ups? Nurse Advise-ERR. 2009;7:1-3.
5. Tuohy N, Paparella S. Look-alike and sound-alike drugs: errors just waiting to happen. J Emerg Nurs. 2005;31:569-71.
6. Beyea SC. Confusing, look-alike, and sound-alike medications. AORN J. 2007;86:861-863.