Bar Coded Medication Administration

October 2007 - Vol.4 No. 10

So you are going to implement bar coded medication administration (BCMA) in your hospital to significantly improve patient safety. Good for you! It is one of the most important things you can do for your patients.

During the course of this effort, you will make many decisions that will have a long-term impact on your operations and, ultimately, the efficacy of your BCMA solution. A key technology decision you need to make is the selection of a bar code “reader” for use at the bedside. This article is intended to help you sort through the options and select a reader that works as expected and serves as a long-term solution that will not soon need replacing.

In February 2004, the FDA published a final rule requiring manufacturers to label certain drugs with – at a minimum – a bar code containing their NDC numbers. To satisfy both the FDA’s bar code labeling requirements and produce smaller unit-of-use packages, pharmaceutical vendors are using an increasing array of sophisticated bar code symbologies that can encapsulate other important information, such as lot numbers and expiration dates. While 90% of products have “classic” linear bar codes, smaller packages require more sophisticated symbologies, such as stacked linear bar codes and composite bar codes. The FDA has reportedly also been approached to approve the use of two-dimensional (2D) bar codes.
There are over 200 known bar code symbologies in existence, but fewer than a dozen are common in the health care industry. With that said, the health care environment is seeing an increase in the types of symbologies on drug products, and this trend is expected to continue. Linear bar codes are relatively simple constructs of dark and light spaces of varying sizes. However, the sophistication of newer bar code symbologies, such as stacked linear, composite, and 2D bar codes that encode more data in less space, strongly supports the purchase of bar code imagers, rather than bar code scanners, for use with point-of-care systems.

Bar Code Types
There are three basic categories of common bar codes: linear, composite, and 2D or “matrix” bar codes. Linear bar codes are the simplest and most mature, having existed for decades. Examples of these are omnipresent in grocery stores and other retail outlets. Some of the well-known linear symbologies in health care include UPC, Interleaved 2 of 5, Code 128, and Code 3 of 9. Some of these symbologies can encode only numeric information, and some can encode numbers and alpha and special characters.

Linear stacked bar codes are permutations of linear bar codes; the symbology is split into two components, so less horizontal space is required to print the bar code. To successfully interpret a stacked bar code, both components in the stack need to be successfully read. Stacked bar codes are common on vials, ampoules, and other products that require a small label.

Composite bar codes are the combination of two or more bar code symbologies printed in close proximity to one another, often with a fixed relationship to each other. The stacked versions of the GS1 DataBar (previously known as RSS or reduced symbology set) bar codes are frequently part of composite bar codes. Composite bar codes can be comprised of both linear and 2D symbologies. Often, for a bar code reader to decode a composite bar code, all components must be recognized. Currently, the composite bar codes seen in health care have a linear bar code component and a 2D bar code component. The drug manufacturers’ move to GS1 DataBar stacked bar codes and composite bar codes was driven by space constraints on drug product labels; some products, such as vials and ampoules, are in very small containers, and high-quality standard linear bar codes generally cannot be printed at a size small enough to allow space for other information on the labels. The need to put more information in less space continues to drive changes in our industry.

2D bar codes, also known as matrix bar codes, are the most dense of the symbologies and can encode the most information in the least amount of space. Data is encoded in relative positions of light and dark spaces. 2D bar codes can be a variety of shapes, including square, rectangular, and circular. Most 2D symbologies have two advantages over linear bar codes: They are orientation-independent (i.e., the reader does not need to be oriented in a particular direction in respect to the bar code) and self-correcting, so smudged and damaged bar codes can often be decoded successfully. Because of the need to package materials in increasingly small containers and to encode more data on smaller labels, 2D bar codes are anticipated to become more commonplace in pharmaceutical packaging and are already used on medical instruments and other items.

Bar Code Readers
Fortunately, there is less variability in bar code readers than there is in bar code symbologies. All readers share some common characteristics; specifically, they illuminate the image to be read and then measure the reflected light. The reflected light is decoded, and the data is either stored (to be uploaded later) or immediately communicated as data to a computer-based application. Bar code readers are either fixed, such as those under a glass plate at the supermarket, or hand-held, such as contact wands, CCDs (charge-coupled devices), and laser readers.

Bar code scanners are the more mature of the laser options, and can be either “straight line” or “rastoring” types. Straight-line scanners emit a single beam of light and can interpret traditional linear bar codes very well. They perform less well on stacked and composite bar codes, especially composites that include a 2D component, as they cannot decode a 2D bar code. Rastoring scanners emit two or more beams of light, can read linear bar codes very easily, and perform well on stacked bar codes and composite bar codes comprised of only linear bar code components. They will also fail to decode 2D symbologies. Additionally, using a scanner to successfully read stacked bar codes and composite bar codes often requires patience and an exact scanning technique that can frustrate the caregiver.

Bar code imagers, on the other hand, can be configured to read all current bar code symbologies that they have been programmed to decode, including linear, stacked linear, composite, and, in the case of area imagers, 2D bar codes. Additionally, they do not require as much attention to scanning technique, resulting in less frustration for caregivers.

Since dependable technologies are significant to the successful adoption of new processes, it is essential to ensure your bar code readers perform well. With the influx of stacked bar codes and composite bar codes, scanners no longer meet the expectation of reliability, creating a strong argument in favor of purchasing more expensive bar code imagers for bedside medication verification. It is important to note that, if and when 2D symbologies become commonplace, bar code scanners will become a liability rather than an asset for BCMA.

Impact on Operations
Bar code readers are a critical part of any point BCMA system. These tools provide the link between the technology and the human being, and they are expected to work the first time, every time. While perfection is not a realistic expectation, consistent scanning success is and should be. Without consistent success, alternative and potentially dangerous practices or workarounds will be used. The bottom line is: Bar code imagers, while more expensive than scanners, can consistently and successfully scan stacked, composite, and 2D bar codes.

Additional Considerations
When selecting peripheral equipment, such as bar code imagers, you should work with your BCMA system vendor to understand their constraints, biases, and ability to provide support for the imagers you select. In the case of bar code imagers, it is not uncommon for a software vendor to “certify” specific devices. Selecting a product from a vendor-certified supplier can save you time and trouble. Some BCMA vendors have invested months in working with specific imager vendors to create the firmware that will enhance the imagers’ ability to work with their product. If you order imagers as prescribed by your software vendor, your products can be delivered “pre-configured,” which will save considerable technician time and troubleshooting. Furthermore, in many cases, your vendor may not be able to invest the time to research issues with non-certified products, leaving you on your own to resolve them.

When selecting bar code readers, you should also involve your bio-med department, as there are differences in the technologies in which they will likely have a vested interest. For instance, some readers may not be permitted in your environment, due to the class of their lasers. In some organizations, class 2 lasers are not permitted as they have the potential to cause damage to skin and eyes. Class 1 lasers, however, do not have this risk. Your bio-med department can also help you differentiate between drop-test ratings, dust- and water-resistance scores, and other esoteric considerations likely more important to them than to you.

Health care organizations implementing BCMA systems should carefully consider the rapidly changing complexity of bar code symbologies and select equipment that both works well today and is predicted to work well for several years in the future. Specifically, the bar code readers deployed should be bar code area imagers, not bar code scanners, in order to ensure successful scanning of a variety of bar code types. Furthermore, consideration should be given to products that are certified by your primary vendor, recognizing your vendor may not have the resources to investigate  issues with non-certified devices.

A senior project manager with Providence Health System, Bruce A. Douglas, FHIMSS, has a BS from the University of Oregon. With over 30 years of IT experience, he has focused on health care informatics for over 20 years.


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