Award-winning formula: Reducing materials while keeping desiccants in place

A single pouch has replaced a double-pouch system for packaging a drug-eluting stent, reducing materials, labor, and storage needs. The new package represents a 50% reduction in waste and a 46% reduction in storage space. Such accomplishments have earned stent maker Medtronic a 2011 Ameristar award in the Medical Device category from the Institute of Packaging Professionals (IoPP).

Developed for Medtronic’s next-generation drug-eluting stent, Resolute, which is currently approved for use in the European Union and is under investigation in the United States, the new single pouch satisfied several objectives. Medtronic’s previous package consisted of a primary Tyvek pouch sealed inside a nonsterile foil pouch. Feedback indicated that users would prefer not opening two packages, and they would like to eliminate the possibility of the oxygen scavenger and desiccant packets falling out of the pouches upon opening, explains Paweena Limjaroen, Medtronic’s principal packaging engineer. Users also felt the package was large and took up too much shelf space, she says. “Medtronic had the largest package on the shelf, so to be competitive, we sought to reduce the overall dimension. It also helped reduce packaging waste and Medtronic’s environmental impact.”

The new pouch consists of a five-layer lamination utilizing a Tyvek header strip/insert. The inner-most layer in contact with the product consists of the same materials from the original primary pouch, while the outermost layer was changed from PET to nylon to add strength.

The new pouch features a Tyvek-polyethylene-Tyvek divider creating two different-sized internal partitions inside the pouch. The larger partition or pocket holds the device (the stent mounted on the delivery system), while the smaller one holds and retains the oxygen scavenger and desiccant sachets. 

The device is sealed inside the large pocket, and the Tyvek header allows the device to be sterilized with EtO. After sterilization, the oxygen scavenger and desiccant packets are then added to the small pocket, and the pouch atmosphere is then modified through the evacuation of oxygen and addition of nitrogen gas prior to final sealing. After the Tyvek header portion is trimmed off, the pouch is then coupled with the instructions for use and placed into a shelf carton.

Medtronic also employed a smaller hoop for coiling the device, dropping from 8.25 to 7.25 in. diam, Limjaroen explains. The redesigned hoop allows Medtronic to assemble the device in part at one facility through the use of removable tubing and then ship it to another for final assembly. As a result, production line space has been condensed by 40%.

Existing heat sealing equipment can still be employed for the new pouch, requiring only a slight modification in gas-flushing technology to accommodate the single-pouch system.

Medtronic subjected the new package to range of evaluations, including ASTM D4169, Cycle 13, Assurance level I. 
Medtronic also assessed the new design using its internal package and label development guidelines, which include criteria addressing environmental issues and impacts on raw materials, process materials, and packaging. Its evaluation includes ensuring that the new package meets EU directives 94/62/EC and 2004/12/EC on Packaging and Packaging Waste and BS EN 13427-13432 standards.

“Our team wanted to reduce the package size as much as possible,” says Limjaroen. Her team’s 46% smaller package did just that, and also succeeded in increasing the number of Medtronic packages that can be stored on a cardiac catheterization lab shelf by 20%, increasing revenue opportunities.

For more details about the 2011 AmeriStar Package Awards from IoPP, visit http://www.iopp.org/i4a/pages/index.cfm?pageid=78.