For patient identification and medication labelling, SVMC opted for two-dimensional (2-D) barcodes over linear barcodes. Two-dimensional barcodes—in SVMC's case, the Data Matrix format—provide more flexibility than linear codes. Still offers three primary reasons for the decision.
First, ease of use is crucial because a cumbersome scanning process can lead to workarounds that jeopardize patient care. Linear symbologies are larger, and therefore harder to scan on a curved wristband. Because smaller 2-D symbols are readable from any angle and can be repeated around the length of the wristband, there's often no need to disturb a sleeping patient just to get a positive scan. "If a nurse is administering an IV drug late at night, he or she can scan any spot on the wristband, from any angle, and get a positive patient identification," says Still.
Second, error rates for 2-D symbologies are 10 to 20 times lower than for linear codes. Perhaps more importantly, 2-D images can withstand more wrinkling and damage and still remain readable.
Finally, though some hospitals must invest in newer scanners with CCD sensors to read 2-D symbols, the cost for these scanners continues to decrease. "Fortunately," says Still, "reliable 2-D scanners are available for several hundred dollars."
SVMC's next priority was ensuring that the printed barcode labels would be durable and reliable enough to produce the consistently high scan rates necessary for ongoing patient identification and medication verification.
Previously, SVMC had been using laser printers to output adhesive-backed barcode labels, which they then attached to wristbands. These wristbands were inadequate for a hospital environment because they were easily damaged and fell apart quickly.
Still and his colleagues selected Zebra Technologies' LP 2844™ direct thermal printers to produce their patient identification wristbands. "Thermal printers are designed specifically for bar coding and produce lasting, durable barcodes that can be easily scanned at the point of care," explains Still. "Also, when compared to laser printers, there is not a significant cost difference."
In addition to the printers at admission, SVMC located five direct thermal printers on the nursing floors, so staff can now print replacement wristbands on demand. Unlike laser or ink jet printers, these machines do not use ink, toner or ribbons. They can also generate single labels on demand, avoiding the waste associated with laser printers, which typically must output at least a half sheet of media at one time. Because loading media is a simple process and the printers require minimal maintenance, they are ideal for networked use anywhere in the organisation.
Still also notes the relative ease of printing 2-D codes. "Generating 2-D barcodes is not any more difficult than generating linear codes," he says, "because the intelligence for creating the 2-D images resides in the printer, not the application software." In its pharmacy and medical offices, SVMC is also using this embedded capability to print 2-D barcodes directly from its Meditech hospital information system using Zebra's LP 2844 printers.