A few years back I had a couple hernias repaired using surgical mesh, a product much like those rolls of garden mesh that keep hilly areas on your property from eroding. When asked in post op to describe my level of pain from 1 to 10, I was unable to come up with a number because at that point the anesthesia made it impossible for me to locate my own ass with either hand. However when asked if I’d like a morphine drip I knew the answer to that question immediately. Surgery went great and I was back at my desk early, wading through emails. About the 5th one I looked at was an FDA alert describing counterfeit hernia mesh that had been discovered in the US healthcare system. I got on the phone to my doc, who knows me well and kept waiting for the punch line when I described the ersatz mesh. I had to send him the email, more than a bit perturbed that a lowly label bum knew about the problem before the guy that probably stuffs several of these mesh products into patients every week. As it turned out I was fine as the mesh that was placed in me, ruining the look of one of the finest navels around if I do say so myself, was from a different manufacturer than the one the counterfeiters had targeted. It may or may not have helped, but having an additional level of security provided by a well designed tamper evident label on the package may have made the counterfeiting more difficult. In the actual alert the very first criteria that they used to describe the bad device was, “A packaging seal that does not tear open smoothly”.
Tamper evident labels are pretty simple. Notice I don’t say tamper proof, since that’s an impossible claim. Nothing is tamperproof, waterproof, or idiot proof. The goal is to make it evident and obvious that someone has attempted to breach the package to get at what’s inside. This is done by by either the label fracturing, delaminating, or leaving a gooey mess where it was on the package or the adhesive bonding with the package substrate to the point that it destroys the package material if removal is attempted. The most basic illustration of this concept is the simple price sticker on a product that can’t be removed in one piece. The epitome would be a package like a CD jewel case or any electronic device that practically requires a switchblade, hammer & chisel, and a pound or two of C4 plastic explosive to open it up. Which brings up a critical point with medical device packaging. It has to be tamper evident yet easy for the OR staff to open, use, and offer a good solid visual as to whether the package has been tampered with. The original tear tab or tear strip was developed as a result of physician complaints. The simple round or rectangular destructible label worked OK but to get it off required either a fingernail, tough when a person is wearing surgical gloves, or the use of a scalpel which then had to be tossed. The simple label is also pathetically easy to copy and fake. So……..tamper evident/indicating and simple and reliable for surgical personnel to open. That seems pretty straightforward but, like most things in our industry, it just ain’t that simple.
There are a few issues that complicate the medical device tamper evident package label and they can loosely be grouped under sterilization, package conditioning, label function, and good ‘ol ASTM 4169. Certain films commonly used for tamper evident seals do not like gamma radiation and they also do not do well at the higher accelerated aging and conditioning temps sometimes used when…gasp….validations and quals are behind schedule. Also, using the tamper evident label to hold together a SBS folding carton that’s stuffed with the double barrier package, a warranty card, and a big thick manual will almost certainly cause it to fail ASTM 4169, the shake, rattle, and roll test. So will the theory “gee, it passed ASTM 4169, lets add a ‘spike the football’ test to the protocol as well”. You think I’m exaggerating? Unfortunately only slightly. Frankly, if the seal breaks when you thump the package you should think about what’s happening inside the box, the canary in the coal mine theory. Finally, when the label is placed on the package there needs to be a clear work instruction about where it goes on the edge of the box. We often print tick marks to aid in this process. These labels typically have a reinforced peel area with small nicks to make sure the peel is reliable and secure. If it’s lined up wrong it can tear prematurely.
Actually there are a few more nuances but the ones above are plenty for a blog post like this one. Levels of security can be added like adhesive void components, holograms, color shift inks, etc., but the basic version seems to be functioning quite well and has been well received in the medical device marketplace. Its a small item that can pay big dividends if any product integrity issue do arise.