medical device

A medical device is a product which is used for medical purposes in patients, in diagnosis, therapy or surgery. If applied to the body, the effect of the medical device is primarily physical, in contrast to pharmaceutical drugs, which exert a biochemical effect. Specific regional definitions of medical device vary slightly as detailed below. The medical devices are included in the category Medical technology.Medical devices include a wide range of products varying in complexity and application. Examples include tongue depressors, medical thermometers, blood sugar meters, and X-ray machines.

Getting contract manufacturers in line

I've spent a great deal of time recently corresponding with our US based main contract manufacturer on various quality issues, mostly paperwork. These guys assemble the electronic/computer part of the device and they're used to consumer electronics assembly. Using this company is about 40% cheaper than a company that specialized in medical device electronics and was ISO 13485 certified.We basically came along, sent them our documentation SOP and told them to follow it while doing any work for us. This didn't happen so we have a bunch of Manufacturing Process Instructions (MPIs) that don't work as device history records (DHRs) and have a few dozen errors such as scribble outs, blanks, no calibration dates, etc that don't fly in the medical device industry. So we've rewritten everything for them and trained their line on what we require and made good progress. I've learned my lesson though and will hand hold the next group through the documentation requirements.We also ended up providing them with calibrated test setups to make it easier to track equipment used and match what we expected. Now we're ready to go though and will be making thousands of these in no time! Or maybe closer to a dozen and then make a bunch of improvements, we'll see what happens

Patching Microsoft Windows on medical devices

Law Firm IT has an interesting post on installing the latest Windows patches on medical devices, including this:"...because the machines were running an unpatched version of Microsoft's operating system used in embedded devices they were vulnerable.Normally, the solution would be simply to install a patch, which Microsoft released in October. But the device manufacturer said rules from the U.S. Food and Drug Administration required that a 90-day notice be given before the machines could be patched."I'm not sure if that is completely correct about a required 90 day notice to the FDA before patching Windows. I'll leave that to a regulatory expert.I do know that any changes to Windows and the medical device software has to be revalidated, at least the potentially affected parts anyway. The revalidation is obviously going to take time and effort and the rewards are often low, especially if you label your device to not be connected to the internet. You want your software guys putting in new features, not screwing around with Windows compatibility for people who are using the device off label. Additionally, the Windows patch needs to be installed, no small feat for a device that is not supposed to be connected to the internet. All of this time adds up and the bottom line is you're never going to be a step ahead of software virii on a medical device, which is why they almost all say do not connect them to the internet.That being said, Windows with the help of one of several off the shelf software programs, such as Clean Slate, Rollback Rx, and Deep Freeze, can be fairly easily configured so that the chances of a virus are minimized, meaning that you wouldn't have to update Windows with every patch. In fact, this seems like a halfway decent mitigation (along with the aforementioned labeling) to your "device connected to the internet" hazard as part of your risk management.

Non conforming materials

Dealing with non conforming materials has become a more time consuming part of my job recently and a topic of debate within the company. The FDA has 21 CFR 820.90 on non conforming product which says:"(a)Control of nonconforming product. Each manufacturer shall establish and maintain procedures to control product that does not conform to specified requirements. The procedures shall address the identification, documentation, evaluation, segregation, and disposition of nonconforming product. The evaluation of nonconformance shall include a determination of the need for an investigation and notification of the persons or organizations responsible for the nonconformance. The evaluation and any investigation shall be documented."The FDA's definition of product in this case includes components and material. This has been interpreted by many as every nonconformance requires a full on investigation into the root cause and a corrective action, pictures, documentation changes and the whole deal. In fact, some have argued that each non conformance needs a CAPA that must be closed before the material can move on to the next stage. That is all fine and good unless you want to make money, lets be realistic here. Besides, as a startup most of the corrective actions don't necessarily get too far. Lets say I get one custom cable out of 20 with a bad crimp that gives an intermittant signal. The signal is checked as it leaves the vendor, but since it was intermittant it wasn't caught. The conversation goes something like this:Me: One of your cables had a bad crimp and the signal was intermittant.Vendor: We're sorry, we check them 100% before they are sent out, return the cable and we will credit your account the $28 the cable cost or just recrimp it yourself.Me: Okay.I admit that getting after vendors isn't one of my strong points (isn't that for purchasing?), but we need these guys more than they need us- I don't want to source another vendor and then wait for their lead time to get more parts. Now if the cable is miswired or the part tolerance is too tight, then I'll fix the drawing, but our device has many parts and from time to time you're going to run into one off problems that shouldn't require huge amounts of wasted effort.On the other end of the spectrum, I do know that the FDA will write you up if you just scrap every non conformance below a certain dollar value without explanation or investigation, so that is out of the question. So far I've been unable to convince people to include routine rework in the manufacturing process, this will be fine until nothing gets done because everything is waiting on evaluation and disposition then we will change. The best solution seems to be to link non-conformances with a risk analysis, then spend the majority of your time on the ones that could lead to patient risk or entire lots of incoming material being bad. At least that way I don't spend two hours on four dirty $2 boxes.

Solvent bonding, polycarbonate to polycarbonate using cyclohexanone

Medical Devices Blog (clever name!) has a couple posts on solvent bonding of polycarbonate, something which composes the bulk of the happy medical device company's assembly, well that and PVC tubing to polycarbonate fittings (see the well done descriptive picture). He is using cyclohexanone to bond the polycarbonate and getting 20 lbf tensile strength. This seems about right to me depending on geometry, and is industry standard for this type of bonding. We took efforts to design out most of the polycarbonate to polycarbonate bonds out by designing custom molded parts, which saves on assembly time and gives a superior product. If the cyclohexanone is still tacky after 18 hours you're probably using too much cyclohexanone.We use a couple different solvent dispensors (one from Ventrex) and fixtures to get the application right and ran a few quick studies to determine the ideal amount to apply. Ventrex may be able to help you out with your application, this is one thing I enjoy and think I do well at- letting vendors do the bulk of work for me.Also industry standard is the ETO sterilization with polycarbonate. At a previous company we tried to gamma sterilize Polycarbonate and that doesn't work well, the fittings became brittle and discolored to varying degrees- that didn't stop us from using them though...Update, yeah I screwed up the title originally, that should be polycarbonate to polycarbonate.

Recent FDA actions

A couple of questionable moves by the FDA have made the press recently.FDA cracks down on Cheerios health claims and sends them a warning letter:According to a letter from the FDA General Mills' advertising violates the federal Food, Drug and Cosmetic Act. The agency said claims that Cheerios ingredients can lower cholesterol within a certain amount of time, all while providing cancer-fighting and heart-healthy benefits, essentially makes Cheerios "a drug" by their definition. And no drug in this country can be legally marketed without an approved new drug application.The company claims what they say is the truth, you just can't say it because Cheerios isn't classified as a drug, which the FDA considers misbranding. I'll save my criticism because you can run through it just as easily in your head as reading it here.And Megan McArdle criticizes the FDA over the new asthma inhalers:And testing these things on only mild-to-moderate asthmatics for short periods of time, which is all the FDA did before phasing them out, seems borderline criminal.This claim doesn't sound like a sound practice by the FDA, you test extreme cases, not the easy ones. That is the whole point of verification and validation.

A blog to read

I'm still thinking up a few medical device related posts, until I do, read Seth Godin's Blog in the meantime and apply it to your company. I spent the better part of my online time during the last two days doing just that, I'm apparently behind the curve because he has been popular for a while now.He is big on maximizing presentations and has several rules for doing this with PowerPoint. He is a marketing guy- I'm not sure if these can be worked in so well with engineering presentations, however some of his general points still apply. If you're giving a presentation, you're selling something, make it count. We have several regular meetings that we spend the better part of an afternoon talking about first pass yield, output, etc. Unfortunately I've decided that in too many of my presentations during these I'm only selling the fact that "I'm doing a good job" and I should instead use the time to drive towards solutions I want.