February 1998

BARCODES

Barcodes. The ubiquitous black and white stripe symbols that appear on everything from shipping documents to food packages have widespread uses in every industry. When people in imaging talk about barcodes, they usually think about applications like inventory, document management or shipping. Most people know that barcodes are reliable and easy to use. Barcodes work so well they're taken for granted.

Hospitals in the New York metropolitan area consume more than 700,000 pints of blood a year. The New York Blood Center has to meet that need. It's a mission critical job. People's lives depend on the New York Blood Center doing its job efficiently and safely.

When the New York Blood Center computerized in the late '70s they decided to use barcodes to label blood and blood products. Codabar symbology is used to record the Unit Identification Number, the type of blood product, blood type and the processing facility. Codabar is not a random choice. While barcoding isn't required by law, those labs using barcodes must use Codabar.

Barcodes are printed on high-quality label pads. Because all medical waste is incinerated, labels must be made with non-toxic materials. They are waterproof and resistant to wear. In the late 1970s the New York Blood Center started phasing in barcodes. As a result they have a variety of barcode readers. They use scanners and wands from Symbol Technologies (Holtsville, NY 516-738-2400) and Welch-Allyn (Skaneatles Falls, NY 315-685-8945).

When a pint of blood is donated two barcodes are applied. One is the Unit Identification Number. This has several identical barcode labels that are applied to the blood bag and the test tubes that collect testing samples. The New York Blood Center allows donors who know they have a high risk of AIDS to anonymously exclude their blood from being transfused (they want the blood for research). A second label is applied by the donor for self-exclusion.

The New York Blood Center keeps blood tests confidential. The Unite Identification Number (UIN) keeps the donor's identity secret, but not completely anonymous. A special barcode label lets them identify high-risk individuals and ensure that their blood is only used for research purposes. The self-exclusion barcodes are encrypted and randomly selected from a pool of numbers. Only the testing lab knows which barcodes identify blood that's not for transfusion. They don't have access to the donor information. Blood that is not to be transfused is immediately quarantined and set aside for research.

After blood has been collected and labeled, the barcode is read into a computer which records the UIN and donor information to a central database. The database is stored on Digital Equipment (Maynard, MA 978-493-5111) Alpha 2100 servers under Digital Unix. The database software is Oracle (Redwood Shores, CA 650-506-7000).

Donors have a unique person number on the database. The New York Blood Center tracks how many times an individual has donated blood and how frequently. If a person's blood has special qualities such as a rare blood type the system can track them. They are then called when there's a shortage of their blood type.

When the blood reaches the testing lab, the samples are separated for testing while the donation is processed for blood products. When the tests are completed all the blood products are labeled and released for use. Rare blood types are frozen for long term storage.

In the testing lab blood samples are placed on microtiter plates. These are square plates with small wells for blood samples. Microtiter plates are also barcoded. Lab technicians fill the wells with blood samples recoding the Unit Identification Numbers with the microtiter plate's barcode on a computer.

This is called building the plate. After that, the entire testing procedure is completely automated. The testing devices perform the tests on all the blood, analyze the results and automatically enter the results in the same database with the UIN. The barcodes on the microtiter plates let the computers track the plate and samples.

When the tests are complete, the donated blood and its products are labeled. If one of the tests comes out positive, the blood is quarantined and destroyed. The donor is advised that there was a problem with the donation and is advised to seek out medical help. If a test result indicates a rare blood type or a donation that has a special advantage, the donor is advised and asked to donate again as soon as possible.

All these steps ensure the blood supply is safe. Before barcoding, the New York Blood Center did everything manually. Aside from the higher cost, there was an increased risk of error. Barcodes have undoubtedly saved the Blood Center money, but they would have switched even if it would have cost more. Maintaining a safe blood supply is one mission critical application that can't be skimped on.

Before the New York Blood Center installed a computer system in the late 1970s, donated blood was tracked with handwritten log books and multipart forms. Each donated pint of blood was given a Unit Identification Number. The UIN was applied to the blood bag and the samples used for testing. As the samples were tested, the results were manually written to a laboratory report. The completed reports were then matched with the blood bag and then labeled.

This work was multiplied when the blood was separated into products. Each pint of blood yields several products: red cells, plasma, platelets and cryoprecipitate. Each product receives the UIN. All blood products are labeled with the collecting organization. New York imports blood from all over the country and Europe. All of it is labeled for origin and retested to insure safety.

Manually recoding all information worked well when the volume of blood was small. As the volume increased, the dangers of manually recording information became apparent. Lab reports could be lost or switched. It was too easy for a technician to fill out a lab report incorrectly. On top of that, the New York Blood Center farms out testing to independent labs. Standards were needed to ensure all labs could be audited and that they followed federal licensing regulations.

Barcodes let the New York Blood Center conduct more than 6,000 tests everyday -- without the risks associated with a manual system. Barcoding has saved the New York Blood Center time and money in processing donations. But according to Ed Streun, director of regulatory affairs at the New York Blood Center, the increase in safety and reliability far outweighs any increase in cost effectiveness provided by barcode technology.