Radio frequency identification (RFID) is getting a lot of buzz in many medical settings and rightly so. That's because it has the potential to protect patients and minimize error in labs and hospitals, while improving the quality of patient care. For instance, in a few years, patients checking into hospitals will receive an RFID tag on their wristband that healthcare personnel will use to access information such the patient's blood type or medication dosage.

RFID can protect individuals from counterfeit drugs, eliminate data-entry errors such as mislabeled pharmaceuticals or blood types, and track mobile-lifesaving equipment, all applications that could make the difference between life and death. A few hospitals are considering using RFID technology to track visitors. Some hospitals are already tagging newborns with RFID bands, which sound an alarm should someone try to abduct a baby from the nursery.

RFID is suited to medical settings because it works without line-of-sight. The technology involves tags and readers that communicate with each other by radio wave to identify people and objects. Tags, or chips, are placed on individuals or objects and can be “read” for their data or programmed with information at distances up to several feet, while the object is in motion, in different orientations, and through liquid (most difficult) and other obstacles. RFID tags can withstand extreme pressure and temperature swings. Readers can also sample many items at once and a tag can store upwards of 30 times more information than barcodes.

A few examples of how well RFID tags can work to protect end-users come from a large manufacturer of labels, printers, and readers. “RFID was first adopted to ensure the right patients are going to surgery and that they, for instance, don't get the wrong leg cut off. Patients in hospitals such as Massachusetts General wear RFID wristbands that are linked to their charts. This lets health workers instantly access patient information,” says Dan L. Williams, marketing manager Avery Dennison Printer Systems, Philadelphia, Pa., (machines.averydennison.com).

According to Williams, RFID tags also help protect babies from bad formula. “Baby formula gets counterfeited a lot because it is so expensive. People were selling outdated formulas to South America, where the paper labels got stripped off and the product resold. RFID makes this difficult because identifying tags are hidden inside formula containers.”

Three tips for better RFID

Williams says several RFID government and industry mandates have packaging managers scrambling to get the technology working. For a smoother adoption, he offers three tips:

• • Purchase RFID printers that are compatible with label stock. Many conventional printers require that labels' embedded chips be positioned in a specified label location. However, print heads in new-generation printers can sense the chip location and jump over it. This is called “Jump the Bump” and it eliminates damaging chips or smearing labels, which cost about 20 to 50 cents each.

• • Test several reader positions for the best one. Readers positioned directly above moving packaging lines might not scan labels on the sides of cartons. To eliminate the problem, RFID labels are being developed that have embedded antennas, which are oriented in several directions.

• • Minimize electronic interference from devices such as cordless phones or networks that employ frequencies close to RFID frequencies. HF technology has been used in hospitals for many years and meets the electromagnetic radiation limits of 3V/m, showing no electromagnetic interference with critical medical devices.

Is that drug counterfeit? RFID tags tell.

RFID can also help to protect consumers from counterfeit or diverted drugs says a company that provides product-authentication systems based on “mass serialization.” During manufacture, or at any time prior to distribution, RFID tags can have a randomly generated code written to a chip or an already embedded code used to identify products. This code is unique to a product at one or multiple levels of packaging. It is stored along with related data in an associated database and is thereby available for authentication.

“Unique product IDs support emerging regulations requiring a certified pedigree for pharmaceuticals. A drug's pedigree represents a history of its complete chain-of-custody from manufacturer to the point-of-sale,” explains Kevin Erdman, president and CEO of Verify Brand, Minneapolis, Minn., (verifybrand.com).

Four states now have ePedigree, or electronic pedigree, regulations at some level of implementation that compel drug distributors and retailers to verify the authenticity of about 32 drugs they are handling. According to Erdman, there are indications that more states may move in this direction and that the FDA could also look at a larger-scale implementation of similar regulations.

Experts agree that ePedigree lends itself well to RFID. There can be several stops for drugs along the distribution chain. A worker at each stop would scan the product, confirm receipt, and create a digital record of this transaction. When the drug reaches stores, ready for sale to consumers, a complete record of its distribution would have been created and stored. Open-standards recommendations are being considered to streamline the creation and exchange of electronic pedigrees among trading partners.

“RFID offers many advantages for advanced production and supply-chain efficiency, and it supports increased and improved product authentication,” says Erdman. “We are working with a variety of RFID tag suppliers to incorporate our system with this emerging technology to ensure authentic and safe products are moving through a more-efficient supply chain.”

No more bad blood

Another take on how RFID technology protects end-users comes from a company that manufactures chips. “Our chips feature our Coil-on-Chip technology. The chip's antenna is formed directly on the 2.5 mm square silicon surface, so they are small enough to attach to specimen or blood test tubes. Instead of manually hand writing and attaching labels, a method prone to error, qualified personnel can input data directly into a spreadsheet-like interface on a PC or laptop attached to a reader-writer. Data recorded can include sample ID, test result, time, date, quantity, as well as brand protection, and anti-counterfeiting information,” says Jeff Giger, national sales and marketing manager for new products and development at Maxell Corp. of America, Fair Lawn, N.J., (maxell-usa.com).

According to Giger, RFID also lends itself well to lab automation, drug discovery, and clinical trials where samples, vials, and tubes are kept frozen. Tubes can be removed from freezers and their tags read immediately without having to remove frost or condensation. In addition, the company's chips let trays containing 96 specimen tubes be read and written to individually and quickly.

RFID 101

RFID is actually a generic term describing several technologies that use radio waves to identify individuals or objects. A typical RFID system consists of a tag that includes a microchip, an antenna, host data-management software, and a fixed or handheld electronic device called a reader or interrogator. The reader also has an antenna so it can send and receive information with the tag.

Tags come in the form of small, rigid, discs, which can be used on bottles, vials, syringes, and test tubes. There are also flexible tags, which can be laminated to cardboard, plastic, paper, or other non-ferrous material and are often used on blister packs, multiple-unit dose packages, and patient wristbands.

Tags can be passive, semi-passive, or active. Passive tags have no battery and must draw energy from the reader to power their internal circuitry that transmits data to the reader. Read ranges for passive tags are a few inches to about four ft. Semi-passive tags contain a battery but the reader still provides power for communication. These tags have a read range from ten to 100 ft. Active tags are completely powered by internal batteries. This lets the reader devote all its energy to transmitting, so read ranges are over 100 ft.

Different tags use different memory. Read-only chips are programmed at the manufacturer with information based on customer specification. The information cannot be added to or changed. Passive tags are typically read-only. Write-once, read-many (WORM) chips let users store information on them once. And read-write chips let users both store and update information.

Data capacities differ from model to model. With memories as small as one byte, tags are simply detected or not detected. A 128 Byte-chip can store small amounts of information such as serial numbers and factory of origin. And 512-KByte chips can store several pages of data such as serial number, item contents, date, time, patient name, and medical data.

Readers capable of programming tags obtain instructions and information from host data-management software. The user or the system initiates transfer of the information to the tag. Readers can be fixed or mobile. Fixed readers can be stationed, for example, in a hospital basement, a room, or entryway to track mobile equipment. Handheld readers, which are similar to Palm Pilots, are manually operated, go anywhere needed, and hold about 16 MByte of information.

Readers and tags communicate based on established protocols at the same frequency.

Medical settings most often use 13.56 MHz because it can go through body cavities, liquids, and metals. Most readers can be configured by the manufacturer with antennas of various sizes and shapes to accommodate the type of tag, frequency, proximity of the RFID system to metals or liquids, and required coverage area.

RFID falls under two incompatible standards: The International Standards Organization (ISO), common in Europe and elsewhere, and EPCglobal, a joint venture developed to commercialize Electronic Product Code, widely used in the U.S. Electronic Product Code (EPC) standards are organized into classes that specify tag technology and generations that specify the physical component and how much data it can hold. Class 0 covers read-only 56-bit tags that operate in the 860 to 930 MHz range. Class 1 covers WORM, and is divided into Class 1 Generation 1 (C1G1), which operates at 860 to 930 MHz and supports 96 bits of data, and Class 2 Generation 2 (CIG2). Gen 2 technologies support up to 2k bits in WORM and 2k in read-write memory. EPCglobal is working to make Gen2 comply with ISO standards.

Common frequencies are:

Low	125 kHz (used in the U.S.) and 134.5 kHz (international)
High	13.56 MHz
Ultra-high (UHF)	433 MHz (active tags only) and 868 to 956 MHz.

“Cut here,” says tag to surgeon

To protect surgical patients, Zebra Technologies, Vernon Hills, Ill., (zebra.com) and one of its partners, ATM Systems Inc., Cheshire, Conn., (amtsystems.com) developed RFID systems that combine printers, “smart” labels, and a medical-grade adhesive. “Most hospitals use Sharpie markers to outline the area on a patient's body to be operated on, which both the patient and the doctor sign with the same marker. But horror stories still abound regarding patients getting the wrong part of their body cut open,” says Matt Ream, senior marketing manager at Zebra. “Our printers encode labels with the patient's name, blood type, and surgery description. This label is then attached to a patient's body in the exact spot surgery will be performed.”

RFID lets medicine bottles talk

A talking-medicine-label system includes a handheld device that reads an RFID label on a prescription medicine bottle and then translates that information in voice synthesis. Scriptalk lets sight-impaired users or those with mild dyslexia hear their correct dosages and other mediation information. “Sight-impaired individuals currently use organizational strategies to keep their medications straight, but it's still easy to get confused and make an error,” says David Raistrick, president En-Vision America, Normal, Ill., (envisionamerica.com). This is such a critical safety concern that the Department of Veterans Affairs has issued Scriptalk systems to about 95% of the VA hospitals in the U.S. In the civilian sector, pharmacies can program medication information on drug bottle labels so patients at home can use handheld devices to listen to the information.

Smart frig keeps track of enzymes

A manufacturer of antennas and pressure-sensitive adhesives has developed a security system that uses an RFID system to track enzymes in a lab refrigerator. “The usually locked refrigerators have built-in readers. When an individual opens one with a card, similar to a credit card, the system tracks the date, time, and name of the individual removing the container. This is also done for narcotic drugs,” says Steve Dominak, business development manager for conductive solutions, MACtac Technical Products, Stow, Ohio, (mactac.com). “We provide the antennas, the foam, and the adhesive that works in the cold lab environment.”