Candid Diabetes

CGMS Update (And, when clever titles and well-thought out posts desert me)

I'm still here. (I actually almost cheesed out and wrote "I'm still standing" glarrrrg - suffer in misery with me if that song is stuck in your head now)

Blogging, for the most part, has run it's course and peaked in Tiffanyland (did you know that there are such things as Tiffanyisms? Yes indeedy...And that the term 'double-double' is in the Canadian Oxford Dictionary?! Credits to the TV screen at the Tim Horton's drive-through this morning for that little nugget!) I, grand disdainer of groupy-stuff (Tiffanyism), actually prefer the community of an online support group to blogging. Except when  something gut-busting funny grabs my attention or I am the recipient of strange events that only happen to me. Erm, so yeah, I'll still be popping around occasionally unless the world tilts off of it's axis and I slide into oblivion.

But since that hasn't happened yet, today's popping is focused on the thing that I don't talk about enough (here): the Paradigm Real Time System. Yes, I am still wearing my CGMS. Big-smile-time: my transmitter (the Gen 1 version, not the fancy new MiniLink that isn't available in Canada yet thank you very much this sucks) is still running. Heh, you may be sitting over there thinking to yourself 'so the frick what?' My aging little/big Gen 1 transmitter is almost a year old. And I use it every day, and have only taken a day off of it here and there for the past 10 and a half months, and it's not dead yet. Really, who cares now right, since the new MiniLink is available (but not in Canada yet - bastards)...honestly I know that this is only a big deal to me. But people, I got a Low Transmitter alarm like TWO MONTHS ago!!! And it's still ticking!! 1 - 2 - 3 - YAY!! So for anyone who might have the old transmitter without hopes of getting the MiniLink anytime soon (and can I just tell you, the MiniLink is seriously small, several members over at Insulin Pump Forums have it and have posted pictures which bring tears of envy to my eyes) this one's for you, low transmitter battery and all.

But, like I said, the MiniLink is a nice dream for us Canadians (I can't tell you how much that ticks me off). Though I haven't seen it myself, I do know that it's small. And rechargeable. And it doesn't require those big ugly transmitter adhesive pads. It's still waterproof and still uses the same sensors as my Gen 1 transmitter, which is a bonus. And rechargeable. Wooftey.

Me and my old transmitter will continue to plug on (baha) until the little sucker dies at which point I'll likely trade it in for a new Gen 1 transmitter (thanks to some deal of Medtronic's where you buy a box of sensors and get a new transmitter free -- I have six boxes of sensors in my fridge. Yes, six. They owe me, seriously). But my stubborn side really wants to see my transmitter die, and I want it to last another two months. Then I win. In Tiffanyland.

But jeez, I have strayed from the whole point of this blog post. I was originally going to talk all about the RT after 10 and a half months of use, but honestly I don't know where to start here. What else can I add to what I've spoken about in the past?

• It's accurate
• I love it, for so many, many reasons
• The sensors can be worn for more than three days. The pump will say "Sensor End" and all you have to do is go into the sensor menu and choose "Sensor Start" to reboot it. Don't disconnect. Do this every three days, and voila suddenly your three day sensor is actually a two-week thing. And bonus, there is no two hour initialization time. If I restart the sensor within minutes of the sensor end alarm I get a calibration request right away and we are live. If I wait longer to restart it only takes about 15 minutes to initialize. I should note, though, that my friends on the forums have experienced a strange occurrence with the sensor re-starts (strangely, I've never had this happen); on the 7th or 8th day, the pump will lose the sensor signal and no amount of trying will boot it back up. So, what they do is disconnect the transmitter from the sensor and then reconnect it (don't take the old sensor out) and then tell the pump that you have a new sensor. Disconnecting seems to reboot the system, so you will have a two-hour wait period but hey, it's better than inserting another sensor! One person on the forums (Drea) reported wearing a sensor for 25 days! I haven't gone that long yet...
• Exercise without having to worry about lows? Check. Sleeping without having to worry about anything? Check. Actually getting the flu and not having to worry about lows and highs and anything else?! Ye-ah check baby!!

And if the proof is really in the pudding (though god only knows how pudding can be proof - of what, I ask??) then here are the results:

March something-or-other-can'tremembertheexactdatetoolazytocheck Lab Results VS Paradigm RT Estimates:

A1c Lab Results - 5.9%
Estimated A1c based on Solutions software of downloaded RT CGMS readings - 6.0%

Need I say more?

8 Month Remarks on the TGMS & All Sorts of Navigators

February 2, 2007 will mark 8 months since I first began using the Paradigm RT system. I know that I've been woefully absent from this blog lately, and that I haven't talked about Minimed's TGMS as much as I've wanted to or maybe should have. I started as one of the first bloggers to wear the Paradigm RT system (and have been using it longer than most) but I've been joined since by my TGMS peers, freeing me up to spend all of my time on the Insulin Pump Forums. And though I am starting to question my future desire to blog, I do feel compelled at this moment to provide you (whomever remains and reads this blog to my most gratuitous delight) with an update.

Besides my rep/trainer at Medtronic of Canada, I have not yet met or spoken to anyone who has been using the Paradigm Real Time insulin pump/TGMS combo for longer than I. Which is a little bit of a PITA, because sometimes it sucks being the first person to do something. I don't know when my 8 month old transmitter is expected to die, I don't even know what it will do when it gives up the ghost. And there's nobody to ask besides my rep, whom I don't communicate with that often because lately she tends to give me the Wrong Answers.  Oh, I know that there are a few people up here in Canada who've been using the system for a good 6 months longer than I have...but I can't seem to connect with these people. I have ended up being my own guinea pig. Squeeeeeeeak.

And as that annoying little furry rodent, I have received email after email asking questions about the Paradigm RT or telling me about how you want one, and you're so glad that I've written candidly about my experiences (I say that apologetically because I've been lacking in the writing area, obviously). So, I've made a list of common questions about Minimed's pump/TGMS combo here, answered solely by the voice of my own experiences over the past 8 months, and supplemented by the helpful posts of members on Insulin Pump Forums. Yes, some of these will be repeats, some you might have already heard. But I hope that it helps to answer or clarify any questions you may have. And, as always, don't be shy about emailing me; I am quite happy to answer!

Without further ado, Candid Diabetes presents:

The Paradigm REAL Time FAQ

Q: Can the sensors only be worn for 3 days (72 hrs)?

A: No way. The longest sensor that I've worn was 12 days; there is a member on the forums who wore a sensor for 19 days!! WOW! I might have to try and beat that now...the trick is that, when the sensor ends, you just tell the pump you want to start a new one. Voila, it believes you and off you go. And an added bonus: when you simply restart the system, it only takes a few minutes to initialize. Most of the time, my pump prompts me for a calibration within 5 minutes of my restart, and the transmitter is up and running again. Some of the people on the forums have noticed that their pump loses the transmitter on about day 7 or 8 (I have never personally had this happen) at which point they remove the tape from the sensor, unclip the connection between the current sensor and the transmitter, and then reclip it and retape. They tell the pump that a new sensor has been inserted and, in most cases, the pump grabs the RF transmission again and it's good for another three days (or longer). When you unclip the sensor from the transmitter, it requires the 2 hour initialization time.

Q: Where can you wear the sensor/transmitter?

A: The sensor can be inserted pretty much anywhere you'd put an infusion set, it's all about personal preference. I've had sensors in my arms, hips, upper abdomen, lower abdomen, my thighs and the sides of my stomach. Thighs and arms are my favourites. For me, there is no difference in accuracy based on the insertion area.

Q: Can you use the sensor if the insertion site bleeds?

A: Yes, definitely. I've had sites bleed upon insertion, at which point I use a tissue and put pressure directly over the entrance, stopping the bleeding. I've had sites bleed periodically throughout their life. It doesn't seem to affect the accuracy of the system, it just looks nasty. And there are ways to avoid bleeding; personally, I change the insertion angle either shallower or deeper depending on the area, and then I leave the introducer needle in for a few minutes after insertion. This has fixed my bleeding problems. A member on the forums puts ice on the site prior to insertion, and I believe that this has helped her.

Q: Is it hard to insert the sensor?

A: Sometimes. For example, my abdomen, which has seen it's fair share of injections over the past 16 years, has tougher skin than anywhere else on my body. Also, the introducer needle for the sensor looks like half of a hollowed out needle, and the sensor is tucked in the hollow area, so it takes more effort from the inserter to push it in. For myself, I find that placing my fingers on either side of the Sen-Serter 'feet' and holding my skin taught helps to eliminate a partial insertion.

Q: If the sensor doesn't go in all the way, do you have to remove it and put a new one in?

A: No. If the sensor isn't in all the way, removing the Sen-Serter (the device that automatically inserts the sensor) and pushing the needle in the rest of the way manually works fine. This can be tough though, and it's important to ensure that the needle is in all the way in order to use the sensor correctly. Pulling the skin taught while you manually push the needle in has always worked great for me, and I've never had to remove a set that didn't insert.

Q: Do you find that the transmitter is large and bulky to wear?

A: I've talked about the size of the transmitter (the gray oval piece that transmits sensor signals to the pump) many times here on Candid Diabetes. My answer, as always, is yes. It's big. It can be bulky, depending on where I've inserted it and what I'm wearing. Do I care? NO. I mean, really, so I'm part cyborg now and sometimes the thing is obviously visible under my clothing. BFD!! Do I think that you should care about the size? NO WAY. All the time I hear from people who say that they are waiting for a smaller transmitter, and I understand, but I can't help shaking my head. Yeah, a smaller system will be nice but the benefits are much bigger than the physical aspect. In comparison to how much the TGMS has helped me, the size is completely irrelevant. Would you buy a smaller car just because it's small, when a larger car is available that is safer and has more features?

Q: How many times do I have to do manual BG tests when I'm using the Paradigm RT system?

A: First of all, I don't believe that any current technologies are reliable replacements for manual glucose testing. As a pumper, you should be testing your BG levels no less than 4 times a day; whether you calibrate that many times is up to you.

Q: Is the transmitter/sensor waterproof?

A: The transmitter is completely waterproof and can be worn while showering, bathing and swimming. In the summer, I swam for hours during the day with my transmitter on and working. Obviously, you can't go deep sea diving with the system attached, and hot tubs are out of the question. But as long as the sensor is well taped, particularly the connecting area of the transmitter and sensor where water should never enter, you can bathe and swim at your leisure. So don't believe anyone online who tells you that it needs to be removed if you make a trip to swim at your local pool. Just be aware of the depth restriction and never let water into the connection.

Q: What does a "Weak Sensor" error mean?

A: The pump will alarm a "Weak Sensor" error when the signal from the transmitter is either not strong enough, or blocked. Moving the pump closer to the transmitter generally corrects this error. The transmitter is still sending data to the pump while the error is being displayed, and upon full reconnection, these values will be displayed. On the forums, we've also noted that a persistent "Weak Sensor" error can indicate that a sensor needs to be replaced.

Q: What is a "Lost Sensor"? Why do 'lost sensor' errors occur?

A: Lost sensors occur when the pump is no longer receiving a signal from the transmitter. This can be the result of having something dense between the two objects, like having the transmitter on your stomach at night while you sleep, and the pump behind your back. RF just can't make it through tissues and bones. "Lost Sensor" errors occur after a series of weak sensor errors that are not corrected. Also see question 1.

Q: How accurate is the Paradigm RT system?

A: You've heard me say it before. Mine is right on the money 90% of the time. Now, that's not saying that all of them are; I've heard from many people both on the forums and outside that they have had instances when accuracy is all wacked out. Can I explain why mine is accurate and others have issues? Not really. I only know that correcting my own errors also corrected a lot of problems in the beginning, and I try to always tell people that they should first scrutinize their own techniques before they even consider blaming the technology.

Q: What is your favourite part of wearing the Paradigm TGMS?

A: Definitely freedom. Freedom from fear of going hypo while I sleep at night, freedom from testing more than 12 times a day every day, freedom from the insiduous highs and lows of sick days, the freedom of being able to go for a run with my dog and actually knowing ahead of time what my BG level is going to do (love those trend arrows)...so many things that would take hours to detail here. I can now anticipate and prevent high's and lows rather than chasing around behind them after the fact. It is awesome, fantastic, every great adjective in existence couldn't begin to describe how much the TGMS has changed my life for the better. Has given me an almost non-Diabetic life...

The TGMS battery in my little gray oval is still going strong after almost 8 months, obliterating those preconceptions that we had about having to replace the unit every six. I don't know how long it will last. All I know is that I've used mine almost continuously since I got it (with only a day off here and there per month) and the battery status still says "Good". Yes, I've heard from others who've had to have their transmitters replaced because they just weren't working properly (in some instances this was the result of erroneous training of Minimed Help Line Staff), and if you want a broad spectrum of experiences than you should visit the Paradigm RT section of the Insulin Pump Forums. All I can tell you is what I know, what I've told you just now and in the past. My experiences have been heavy on the good side, and I'll gladly shell out another $600 when my little transmitter dies, if necessary.

Oh, and for those of you who are avidly waiting for the Freestyle Navigator CGMS, have a look at this:

Diabetes Self-Care

It's a blog from a lady named Wendy who is on a trial for the Navigator! Lot's of pictures and she explains things quite well.

But honestly, I know that I might be the exception but my RT seems to work just as well in terms of accuracy! And with the RT I can fool the pump into thinking that I've put in a new sensor, thus saving major money (though yes, I do have 100% coverage on insurance but still...) and mine's hooked up to a pump. Yeah the Navigator sounds great but it honestly doesn't sound any better than what I've got! Then again, I've never worn the Navigator so I can't realistically compare the two.

When it comes down to apples and oranges, though, I think I'll stick with my Paradigm RT. And hopefully soon I'll be wearing a smaller, all in one and still waterproof sensor/transmitter combo (slated for 2007).....

Paradigm RT: Accuracy & Placement

It's been three months since I hooked up to my smokey Paradigm 522 and its continuous glucometer, and I've learned a good deal during that time. My pump also did a bungee-jump off of my waist into the toilet...but that story is better left for another day. Or never. The jury's still out on that one.

The TGMS (telemetered glucose monitoring system) and I have a real love/hate relationship, moreso than I've ever had with my pump. Unlike my pump, however, I can take a break from the TGMS when I feel like it, whether it be for hours or a few days. I just remove the sensor and the seven billion layers of OpSite and stash the transmitter in my supply drawer, and I'm free without any repercussions. Err, well, except for the fact that I now have to consciously remember to do 12+ manual tests a day, whereas before it was routine. Amazing how quickly and easily good habits can be changed, isn't it?

To date, my largest complaint about Minimed's TGMS is the placement factor. Though the sensor/transmitter unit is really not that large, placement of the transmitter can be a real issue. I can put the sensor anywhere...but then I have to think about the three or so inches to the transmitter itself (the oval disk that sends interstitial BG readings to the pump every 5 minutes) and anything that might interfere with its mechanisms.

Transmitter Placement Problems

Girls who wear fitted clothing will get this one. I favour my upper abdomen for site placement of the sensor because I rarely wear my infusion set in any part of my stomach. Great, lots of room, right? Not so much...if I go too far to the mid-area with the sensor, then the transmitter is a big lump under a chic blouse or tight shirt. I've learned to tuck the transmitter up under my breast in order to hide it, but then the bra doesn't fit quite right (I'm well endowed). So I started inserting the sensor closer to the side of my rib cage, and tucked the transmitter either around my torso towards the back, or directly underneath the sensor site (remember, too far toward the belly button and it's obviously visible, especially under light shirts where the grey of the unit peeks through). The first time I did that I was woken up five times throughout the night to a nice "Weak Signal" alarm. If I sleep on the transmitter itself, or even sit on a couch with the unit pressed into cloth, the RF signal is lost.

So I moved on to my lower abdomen, trying it once and then never again. I favour low-rise slacks/jeans/etc. which are not conducive to placement of either the sensor or the transmitter. And using my hip caused the same interrupted signal problem as the sides of my upper abdomen.

Next in line was to try my upper arm. The clear winner, by a long-shot. I bring the transmitter up towards my shoulder, mid-line, and I haven't lost the signal once. And unless I'm walking around in a sleeveless shirt, the transmitter is completely inconspicuous. However, the obvious obstacle to placement of the sensor on one's arm is the placement itself. I just can't do it one-handed. Hold this while removing that and peeling layered tape...it requires two hands, no less (hell, sometimes three would be handy! *pun intended*). I can proudly insert any infusion set in my arm, even the Silhouette and sets with no injector, but I cannot see my way around a five-fingered job on the TGMS. So every time I want to put a new sensor in my arm, I have to have help. And since I don't always have help, arm sites are few and far between.

Accuracy

Everywhere I look, people are having accuracy problems. Or they're criticizing the accuracy of the Paradigm RT system (Enter Soap Box Rant: I'm irked by the people on the www {Note: the OC is not included in the aforementioned www} who have not even used the Paradigm RT system and yet are bashing it left and right and five ways 'till Sunday. Let me say this nicely. You've never used it. Please refrain from vocalizing your critical opinion on a technology that you are not personally familiar with. Especially when you are presenting blatantly incorrect information. Bugger it. Shut the hell up, you. What the hell do you know, moron? You don't even take the time to gather the correct facts {read: quit your damn day job} before spewing them all over the place. You haven't even used the damn system; don't knock it 'till you try it! Then you can bash the hell out of it if you feel so pessimistically inclined. Soap Box Rant Concluded. Please come again.). And though I don't deny that I've heard my fair share of accuracy issues by RT users - resulting in the obvious conclusion that the system still has many a bug waiting to be squashed - I personally have had very few accuracy problems during the past three months.

90% of the time, the sensor is reading within about 0.8 mmol of my glucometer, no matter what my blood sugar level is. High or low, it's not off by much. On average, I see a 0.3 mmol discrepancy between the sensor and manual BG tests per day (full day averages of sensor values compared to the glucometer value for a one month period). Interstitial lag time, possibly? Or could it be the simple fact that I am very well controlled, with few fluctuations, possibly resulting in a lower error grade from the sensor?

Alas, I am not an expert on this subject, so I leave it in the hands of Medtronic's R&D department. All I know is that the remaining 10% can mostly be blamed on my own self. Sensor insertion errors are generally the cause of any readings that I've had that have been +/-2.0 mmol outside of manual BG's. I've learned that I can calibrate the sensor successfully on a low or high BG as long as the ISIG (the signal strength value between the sensor and the pump) is above 5.00. And the one day of totally wacked out sensor readings (they were up to 4.0 mmol higher/lower than the glucometer pretty much all day) that I experienced was corrected when I removed the 10 day old sensor and inserted a fresh one.

Which leads us to the conclusion that the value of the RT is not in the values themselves - as Caro so eloquently put it - but in the trends that those values project. Up is up, no matter what the number may be (and vice versa), which is significant in pinpointing which basals and ratios need to be tested, and when.

But I also find great value in the flexibility of my own testing, as I've mentioned before. I can trust the TGMS enough to not have to manually test on my knees under a restaurant table (unless I feel the need to) or in a dark movie theater.

And that, in itself, is a small freedom that is large enough to hold on to.

Whip It Good

I sit here, at my desk in my cubicle as the rain pours outside, raging at my body.

On Wednesday morning, I woke to a very pleasant blood sugar level of 16.2 mmol (ketones, meet body - body, meet ketones; now why don't you go bug someone else?). My body cackled maliciously as I spent the whole day going to dangerous lengths to see at least an 8.0 on my little grey meter. I temp'd my basals up, going as high as 200%. I bolused indecently unsafe amounts of insulin, both via the pump and the needle stashed in my glucometer case. I cleaned the (work) place out of water (and styrofoam cups) and ate bird-worthy snacks throughout the day. I checked the infusion set, changed the infusion set, swore at the freaking infusion set in the privacy of the ladies washroom while my stomach pitched violently in an effort to invade my throat. And oooh how convenient it was for my body that I had removed the CGMS part of my pump the previous night in anticipation of a break. Yep, I got broke but good.

I learned that it was not my infusion set. It was not the insulin in my pump. I did not have the flu or any sort of cookie-tossing-related illness (I have the immune system of steel - take that invading pathogens!). It was not a full moon or the result of parting my hair on the right instead of the left.

I learned everything externally possible that it couldn't have been. What I never learned is what it was.

Hello, deja-vu, come on in and sit your black-cat butt down. Recent history is repeating itself today.  And though I'm wearing my CGMS it's not doing me a bit of good. Unless it's considered good that the fricking thing confirmed my high BG level this morning (after I slept in and was late for work - and let me tell you I am NEVER late for work!) only to decide that the day-and-a-half old sensor on my upper abdomen is bad. Beeeep beeeep beeep beeep...BAD SENSOR. Excuse moi, Monsieur CGMS, but can we please discuss your bad-sensor ass and the fact that you're pissing me off and when my BG is high I turn into the Witchiest Bitch in the West so can you please just DO AS I TELL YOU!?!? Thank you in advance, your cooperation is greatly appreciated. Fucking you sincerely, The Mile-High Bitch.

OK, OK, so the whole asshole-no-good-CGMS thing was a slight white lie. A fib, if you will, for dramatic purposes. And to prevent the word-spewing from becoming monitor-through-the-widow spewing. The 24-hour screen on my pump did disclose the fact that last night, at 12:58 a.m., my BG level was a nice steady 5.8 mmol until the jets were fired up aaaaaaaaand TAKE-OFF! Ladies and gentlemen please fasten your seatbelts and refrain from sexual activities in the washroom because we've got turbulence ahead! Captain, there's a 14.3 at 3 o'clock! Shoot the bastard down! But wait, today's lotto 6/49 includes the coveted prize of sleeping through the siren of the pump! (merchandise is final sale, and cannot be returned or exchanged) And as a bonus, we will throw in a little bit of sleep-button-pushing, which you will not remember but will silence the shrill wail of the machine that is trying to help you! Yes indeed, ladies and gentlemen, what a ride it has been! Thank you, buh-bye.

The latest BG lottery number: 9.4 mmol. Under the 'O'forfucksakes...

And the five-minute numbers on my pump screen have resumed. HA! Ha-Ha-HA-HA and a little bit of nyah-nyah-nyah-nyah! When all else fails, result to verbal vomiting. It's cheaper than stomping.

Now, I wonder how I go about having a nice little chat with my liver...

Bigger & Better - The Guardian REAL-Time System

One of the things that I love about using an insulin pump from Medtronics is their consistent system upgrades. Since purchasing my first pump over three years ago, I have used:

1) My first pump was the Paradigm 512, which cost me (or my insurance company, to be exact) $5000.00. It was the first pump to support RF technology with the BD Link meter and the first generation of pumps with a Bolus Wizard.

2) I spent $500 about a year and a half later, and upgraded to the 515. Additions were the adjustable IOB (insulin on board) factor and the ability to access the backlight from any menu (to name a few).

3) The upgrade about a month and a half ago to the Paradigm REAL-Time 522 cost me $1100. It included the transmitter and the related system upgrades, which I've detailed in previous posts.

Add that up, and I've only spent a grand total of $1600 out of my own pocket in order to use the most current technology.

And Medtronic just keeps 'em coming.

The newest 'thing' to come down the pipeline is the Guardian REAL-Time CGMS, which has just been approved by the FDA. Up here in Canada, we diabetics can get a prescription from our physician and purchase the current Guardian RT, which is the continuous glucose monitoring system that does not interact with the pump. The RT, though it shares the same transmitter/sensor system as the Paradigm REAL-Time unit, has a distinct wireless monitor inherited from it's predecessor, the CGMS Gold. The current RT unit displays real-time blood glucose values every five minutes on the screen of the monitor in addition to the current time and alarm status. Unlike it's sibling, the Paradigm 522/722, the RT does not display graphs of 3 and 24 hour blood glucose levels.

But it will.

The new Guardian REAL-Time CGMS will reportedly contain the same graphs as the Paradigm system, and will also incorporate audible alarms identifying increasing or decreasing trends in BG levels. When the monitor detects a consistent fluctuation in blood glucose levels, a user-set alarm will go off to notify the user and assist in preventing highs and lows before they occur. For those of us with the Paradigm REAL-Time system, this feature is simply an add-on to the trend arrows viewed in the graph screens, an audio cue to compliment the visual.

And the coolest part about the whole system? Medtronics has scrapped the ugly old CGMS Gold monitor and replaced it with a unit that looks exactly like a pump, without the reservoir.

 

Details at this point are sketchy; Medtronic, in true fashion, is not offering up much technical information to the public. The Guardian REAL-Time CGMS is stated in press releases to be available nationwide by the end of this year but, as we all know, time is a very flexible thing with these companies.

And what does this mean for those of us using the Paradigm REAL-Time insulin pump? I'm not sure. I've emailed a zillion questions to my contact at Medtronic of Canada to see if she can bring me into the inner fold of the hush-hush wetellyouyoumustdie club, but at this point I doubt that even she has been invited.

But, as always, what I know you'll know so stay tuned!

It's a Love-Hate Thing

I love my pump, except for when I'm feeling lazy and don't want to change my infusion set. When I just do not feel like poking holes all over myself anymore. Or when its bulk on my hip wrecks the line of a tight shirt. Then I hate it.

But I hate it out of love, because no way in hell (sorry cute t-shirts) am I giving it up.

The three weeks that I've been using the TGMS sensor/transmitter combo that works with my pump is not enough time to develop the love-hate relationship that I'm sure will exist. I'm still basking in the glow of knowing my blood glucose levels 24/7 and the many wonderful things that entails.

Such as:

A Few Reasons I'm Feeling the Love

- Knowing what my BG levels are all the time. I've mentioned this a few times, and I will continue to say it because this is the biggest benefit of the TGMS. Prior to getting the system, I was entranced with the idea of not having to test as often as I do. The reality is that I still average about 6 manual tests per day (my top being 19, and 2 on the low end), half of what I was doing prior. I have come to the realization that the real freedom of this system is not that it replaces manual blood glucose tests, but that it gives me the choice as to when I want to do those tests. I no longer have to pull the black case out when I'm in a restaurant at lunch with my co-workers. I can sit in a dark movie theatre and eat popcorn, and I don't have to find sufficient light to use my glucometer (have you ever used the backlight on your pump for this? That's a real treat...). And the real benefit of the TGMS is seeing exactly what blood glucose/insulin/exercise/food/etc is doing at any given time of day.

- Micromanagement. Andrea asked me if I was finding my treatments to be anymore aggressive with the TGMS as a guide; the truth is that I was always very aggressive, pre-pump days to date. The difference is that now I can catch any fluctuations in BG levels before they actually occur and prevent them when my BG is still at an acceptable level. My ability to micromanage my disease has increased ten-fold, thanks to my little pump/sensor/transmitter gang.

- The alarms are a god-send. I have been woken from a sound sleep at night a couple of times by the siren of my pump. A completely inexplicable, unexpected hypo. That I probably would've slept through...and woken up in the morning feeling exhausted - without the ability to see why. I have a threshold set: 3.8 (68) for lows, 10.9 (196) for highs. Any time my BG goes above or below these numbers (respectively) the pump beeps. If I don't answer it within a certain amount of time, it sirens and then vibrates. I always verify with a manual BG (especially with lows) and have not yet had a false alarm. Picture this; no more worrying about having a severe low while sleeping and not waking up in the morning. So so great, especially when you live alone.

- I am enamored of the trend arrows that show next to my BG level on the pump screen. They are so incredibly useful when it comes to micromanagement of this disease. It's difficult (though possible) to catch fluctuation trends with manual BG tests; the TGMS does all the work and lets you know if your BG is heading up or down. I can look at my BG on the pump, and if there is one arrow I can prevent highs or lows by temping a basal to compensate. And if two arrows are displayed, I know that I need to take more immediate action, in the form of either a bolus or carbs. Prevention is the best medicine...

Though the pro's of this machine far outweigh the con's, there are several things that could see some improvement:

The Hate Factor

(OK this is not really a hate thing because at this point there's nothing I hate about the system...think of it more as little pet peeve factor)

- The transmitter (the oval shaped piece that connects to the sensor and 'talks' to the pump via wireless RF) could be smaller. It should be smaller. And I've heard talk that next year it will be smaller (but don't quote me on that). It's not that it's ginormous, because the truth is that it's smaller than I had originally expected it to be. But it does show under tight shirts (though the many people I've asked say it's not noticeable; could this be a matter of simply knowing it's there?) and placement can sometimes be an annoyance. I'm not the type to be self-conscious about this (you should see my hair today!) but if you are, then this will be a problem.

- The little adhesive pad that anchors the transmitter can be a serious pain in the ass. It is a very thick pad that does not 'breathe' at all. Can you guess what kind of problem that causes? If you thought 'itchiness' then you're right on the money. When I'm sitting at my desk at work in front of my computer, not moving much, I don't feel the adhesive or the transmitter. But when I'm active (which I often am) and sweating (hello, summer, people) then it itches like the devil. To fix this problem, I place a similar sized/shaped patch of OpSite down and then put the transmitter adhesive pad on top of the OpSite. No more itchies.

- The sensor itself is hard to manually insert. I am all about making sure that I can manually insert any set, rather than having to be completely dependent on an inserting device. Well, I can't manually insert this one (yeah, I'm a little bitter). The sensor itself is introduced subcutaneously by a half-needle. Picture a needle, cut it in half lengthwise, and you have the introducer needle. The sensor is snugged into the hollow area of the needle. I tried to insert it by hand once. It was very, very bad. It hurt like the dickens and I had to push very hard to get it to the half-way point, and then hit a brick road-block. The bad boy just didn't want to go any further, and I was pushing so hard at that point that all I was doing was causing a dimple in the skin. Can I please say, Ouchorama?!? I will try it again, there's no doubt about that. Tiffany will emerge victorious. But at this point, it's Sensor: 1, Tiffany: 0.

- Minimed made the sensor hub a pinkish colour (by hub, I refer to the part of the sensor that sits directly on top of the skin but is connected to the sub-q part). I love pink. But this was a bad idea. Why, you ask? Well, it's hard to see any blood through a layer of OpSite (or IV3000, if that's your personal preference) and that pink hub. Not that you should bleed, but given the initial problems that I had in the first few days, this was a misjudgment on Minimed's part. Think clear, or even gray, people! Give us some contrast!!

- The 522/722 pumps do not work with Minimed's Solutions software. I, for one, really wish they did. Although the reports available in Carelink are acceptable, it lacks the versatility of the Solutions program. I have told Minimed this, and I have small hope that they will fix Solutions to accept the Paradigm 522/722.

So far, those are the only issues I've had with the unit, and as you can probably tell they are minor. And tolerable.

There are also a few mentionables that I want to get out here. I've talked about them before but cannot stress how important they are:

~ Accuracy: I have heard a few people (note: these are people who are actually using the transmitter) say that they've had accuracy problems with the unit. I, personally, have not had any reading discrepancies that have not been my own fault. The key to using this system successfully is to take the time to find out why it is not working properly, and then fix it. Nine times out of ten, I am to blame for inaccuracies, discrepancies, error messages, false error messages, etc. I think that a new user would very easily become frustrated with the possible problems and rather than doing some detective work to find out the why, said user would just blame the unit and throw it in a drawer to collect dust. If you are not willing to be proactive with every aspect of this system, then don't waste your money on it, because chances are it will not do you a spit of good. This is a user-dependent machine, and if you're not a dependable user, then the machine will not be dependable either. However, if you are consistently proactive or willing to be, then chances are the Real-Time system will work successfully for you, as it has for me.

~ Again, and again, and again: The sensors can be worn for more than three days. I've been going seven days with mine. No rash or accuracy issues, either.

I'm sure that I haven't answered every question that you may have about the system, so anyone who needs further information is urged to float me an email. I'll do my best to give you my opinion based on my own personal experiences, and hopefully you will have a clearer idea of whether or not the Paradigm 522/722 system is right for you.

Grading On the Curve

Well, we're coming up on two weeks of bliss, my litte TGMS and I. Which calls for some thoughts on the learning curve of this bad boy.

Point form, in no particular order, here is what I've learned:

- The sensor/transmitter is not called a CGMS. Minimed has coined it a TGMS. Betcha can't guess what that means, eh? I'll make it easy on you...google it. OK, OK. It's a Telemetered Glucose Monitoring System. All this name change refers to is the automatic, wireless transmission of data to the pump (specifically: biotelemetry).

- After a frustrating first few days, I finally clued in about the following:
      - If the sensor is bleeding, profusely, it is not deep enough
      - If the pump keeps blaring the calibration error over and over and over, the sensor has NOT    been inserted properly
      - If there is a big difference between manual BG and the TGMS BG (big meaning more than 1.0mmol) the sensor is not inserted properly
      - If you can't guess, I had some initial insertion problems. Remember I told you about the    spontaneous hemorrhaging problem I was having? Well, it caused a lot of the above problems. Errors up the ying yang. So I smartened up and looked for the root cause: the sensor. I followed logic, and the massive amount of blood that was occurring could've only been caused by one thing - surface veins. So I inserted the next set just a leeeetle bit deeper. My CDE/pump trainer had advised that depth of insertion was so important...and I learned that it is. As long as you aren't depending solely on the inserter to pick the right depth.

- So, to sum up the above: if you're getting scads and scads of errors (calibration error, bad sensor, whatever) or BG readings 1.0mmol+ above or below your glucometer, you can safely assume that you are not inserting the sensor properly.

- Sensors will last SEVEN days. Yep, you read me right. I wore my last one (which was the first insertion fix) for seven whole days. And it worked fabulously. No decrease in accuracy. No redness or infection when the sensor was removed. In fact, it looks better than many of my insulin insertion sites do!

- I can hide the transmitter part (which is a bit bulky) by setting it directly under my breast when the sensor is on my abdomen. Or near my armpit when it's on my arm. Voila, it is practically invisible!

- IV3000 sucks. My big. Fat. Toe. It lifts after two days of wear. Uggg I hate it!!! I have always used OpSite Flexifix for needle sets, and after using the IV3000 that was included with my transmitter when I first got the 522...well, I'll just keep on using the OpSite, thank you very much.

- Instant granola makes my BG level spike slightly within a half hour of eating, after which it normalizes. An hour later (about) it causes another, larger peak that does not instantly come back down. I can now dual wave with precision for this, and hold my P.P. (post-prandial) glucose peak levels below 9.0 mmol. It rocks!!

- I never calibrate if the Sensor Isig is below 5.00. I can calibrate successfully on a low BG as long as the Isig is above this number; otherwise, the sensor readings get wacked and I have to recalibrate to normalize.

- The pump will not lose the transmitter signal when it is sitting eight feet away from me while I'm in the shower. But if I sleep directly on the transmitter, 9 times out of 10 I'll get a weak signal error.

- The Solutions software does not work with the 522. Excuse me a moment while I wipe away my tears... I tried it. And tried. Nope, sorry. No Paradigm pump detected. So now I am consigned to using the CareLink program. Which is passable, but in no way is it as versatile as the Solutions Software. (Are you listening, Minimed???)

As promised, the good/bad post will be making its way here soon (sorry, Andrea).

Dispelling Myths About the Paradigm 522 & Glucose Sensor

...but first, head over to Jim's Site and welcome him as the newest member to the DOC!

So I was doing a search to find anyone else who was talking online about their experiences with Minimed's new Real Time System, but rather than finding any personal accounts, I hit on a minefield of questions and suppositions about the Paradigm 522/722 system. The misinformation is much more rampant than any factual details (something that Minimed really needs to rectify) and I was  blown away by some of the things that I read on forums and message boards. People were reading - and in some cases citing - technical studies and putting their own spin on results to the point of outrageous propoganda. So I've decided to use my own experiences as a way to dispel the myths that are circling the www.

DISCLAIMER: You should never ever ever believe anything you read on the internet, unless it's an established medical or professional organization (and even then, take it with a grain of salt). That includes my website. These are my personal experiences, and I'm not interested in quoting any clinical studies or medical reports. Those are found in triplicate on the www, but actual real experiences are not. I'm just telling it as it happens to me, and as always YMMV.

MYTH: The Paradigm 522/722 receives real time BG readings from the sensor, and then adjusts insulin accordingly.

FACT: No. No. NO. That is the dream-come-true-but-only-a-dream closed-loop unit. The technology that we currently have is NOT sensitive enough to deal with the checks and balances that the body requires (nor is our available insulins). The sensor only transmits the readings to the pump, and the pump only displays those readings. Any action taken as a result is completely user-dependent.

MYTH: The sensor can only be worn for 72 hours (3 days) and no longer. Do not pass go, do not collect two hundred bucks. After 72 hours the sensor dies and that's the end of story.

FACT: This is blatantly untrue. I am on day 4 of my current sensor. Ninety-six hours, baby. In order to get FDA clearance, Minimed had to add a safety feature that shuts the sensor off after 72 hours. The reality is that, once the sensor shuts off, I can tell the pump that I inserted a new sensor and it doesn't know that I'm still wearing the old one. Voila, three day sensor turned into six day sensor. Money saved big time. And the warm up period is only about 15 minutes when I reuse the sensor. So now you may be asking yourself how valid it is to wear the sensor for over 72 hours. Well, that question is really only one that you can answer for yourself. Just as you have to decide for yourself how long you will wear an infusion set with a teflon cannula. The big difference in this instance is that nothing is being infused through the sensor; in fact, the sensor is not even a real cannula. No insulin being infused means no breakdown of the site area. So the chance of tissue rejection is lowered, as is tissue damage. This will probably be a controversial area, as some people tend to build scar tissue easier than others - for example, I occasionally wear an infusion set with a steel needle for well over the recommended time of two days, and have never experienced hypertrophy or lipohypertrophy. But whether you choose to push the bar on this subject is completely in your own hands.

MYTH: The Real Time BG readings have a lag time of 10 minutes.

FACT: The sensor readings only lag when there is excessive fluctuation, such as a sudden low. Once the interstitial blood glucose has normalized (and I'm talking about the actual blood in your body, not the sensor reading) then the sensor itself takes a couple of minutes to catch up. Let me repeat that just in case: THERE IS NO LAG TIME DURING STATIC BLOOD GLUCOSE LEVEL PERIODS. What I see, I see in real time, unless my blood sugar level is taking a nose-dive. And in these cases, my readings show the real time sensor is right on the bang all the way down. I find that it's the coming back up that lags (YMMV). Why? Interstitial fluid doesn't reflect rapid changes as soon as capillary blood does (due to systemic processes), similar to alternate site manual testing (like your forearm).

MYTH: The sensor can only be worn on the abdomen and thighs. (the problem here being lack of available sites)

FACT: The sensor can be inserted anywhere that your infusion set can be inserted. Upper abdomen, lower abdomen. Thighs, butt, hips, arms. The only thing you have to watch out for is that it cannot be placed within 2" or less of an immediate infusion site or manual injection site. Why? Insulin. Interferes with sensor readings. Makes sense, right?

MYTH: The transmitter has to be replaced after 6 months.

FACT: Another FDA submission thing. According to my CDE/pump trainer, people who are using the systems here in Canada are finding the transmitter to last longer (dependent on level of use, of course). She said that they're seeing a lot of frequent users hit the 18-month mark.

MYTH: The sensor doesn't read any values below 2.8 mmol (50 mg) and above 20 mmol (350 mg).

FACT: This supposition is close, but wrong. The threshold to display readings for the sensor is 2.2 mmol - 22 mmol. Whether that makes a difference to you is UP to you. The sensor still alarms above or below the threshold that you set, and I figure if I really want to know the number then I hit my glucometer (which, surprisingly enough, has a threshold too!). The screen will display the real time BG level as either "Below 2.2" or "Above 22".

Remember that these are all fact based on my own personal experience and that of my CDE/pump trainer. You make what you will of this information. But please be very wary of the information that you might find online about this system; remember, the people who are making these erroneous assumptions are not using the real time glucose monitoring system, and never have. And chances are they're neither scientists in the medical field nor physicians.

Personally - and speaking from experience - I would recommend this unit to anyone with Diabetes. But it has its limitations (will be touching on that in next post, per Andrea's request) and is only as perfect as the person utilizing it.

Locked and Loaded! (AKA - Cool Paradigm 522 pics and what I've learned so far)

Can I just tell you: I LOVE THIS THING!

I finally received the sensors for my Paradigm 522 on Friday night. The small box came encased in an even larger styrofoam carton, packed with paper and a gel pack. It was like Christmas in June. I was too excited to wait and impatiently ripped into the box as soon as I got to my car. Each little sensor lay enticingly in its' clear blister package, just waiting for insertion, and I couldn't make the poor things wait. So I popped one in as soon as I hit the door.

The sensors are inserted with the Sen-Serter, and my pump trainer recommended that manual insertion be avoided (for depth accuracy reasons). The first sensor that I inserted caused me a bit of trouble; it didn't insert all the way, and I had to push it in myself as best I could. Unfortunately, the design of the sensors doesn't make this easy. But it is doable.

It bled. And bled. And bled. The manual states (in bold, no less) that one should never hook the transmitter up to a sensor site that is bleeding. Press gauze or tissue on the area for three minutes blah blah blah and if bleeding stops hook up blah blah blah if it doesn't stop after five minutes remove the sensor and insert a new one. Blah blah blah. Yeah, well, Minimed's not the one purchasing these suckers for almost $50 a piece (that's CDN $, people). OK, neither am I, but it's the principal of the thing. I managed to stop the bleeding initially and hooked the sucker up. But it bled (and sometimes badly) periodically as I was wearing it.

Now, here's a big tip that I learned by trial and error: Tape this sucker down, and tape it good. Pretend it's a hockey stick and tape the living hell out of it. Why? Because the first sensor I inserted slipped right out after only 20 hours of wear. Here I am, getting a million alarms (Self test failed, Calibration Error, etc etc) and I can't figure out why...until I get frustrated and yank the tape off. Lo and behold, the inserted part of the sensor was laying right on top of my skin in a pool of blood. Whoops. Lesson learned. The picture to the right is the current sensor (inserted today) that *fingers crossed* will not slip the joint. One layer of IV300, two layers of Op-site. I will prevail!

After insertion and connection to the Transmitter, the pump has to recognize the new sensor. This requires only a few button pushes, but there's a two hour and twenty minute wait while the system initializes, during which no BG values are recorded. Once the system has finalized, the pump displays a 'BG NOW' alarm for calibration. A quick finger poke and the system is all go.

The calibration part is a biggie. Especially that first calibration. I've learned that if I do the initial calibration while my BG's are swinging high or low, I will have up to a 2.0 mmol difference between the pump and my meter. I was expecting this from the research that I did prior to purchasing the 522, but it's a lot different when you're actually trying to get the system to jive with glucometer values. The unfortunate part is that you have to calibrate the system or the pump will just keep on bugging you to do it, and you'll get a whole wack of errors. So here's what I did. Calibrate it on the low or high number. Then wait until your BG's have stabilized and calibrate it again. At this point I was 2.0 mmol higher on my glucometer than the results of the transmitter, and I got a calibration error. So I waited fifteen minutes (this forces the transmitter to restart itself), took another manual BG, and calibrated with that. Voila, every reading I've had since then is within 0.2 mmol of the glucometer (yes, people, it is accurate!). And I write off the half an hour of wacked out sensor readings that occurred in the interim. Not bad. Not damned bad.

So far, those are the only problems I've encountered with this system. Everything else is roses. It is unbelievably exciting to be able to see exactly what your BG's are at any given time without having to unzip the pack, pull out a test strip, poke a finger, entice some blood from that finger, and wait five seconds. One button push and I can see what my BG is while I'm driving, or gardening, or walking Mollie...you get the picture. Sure, the transmitter is not tiny by any stretch of the imagination, but the trade-off is worth it. I can go into my daily totals menu and see an average of ALL BG's for the day - all 258 (or so) of them.

And then there's the status screen. When I first hooked up to this bad boy, I was literally looking at the 3-hour screen every five minutes. After almost two days of wear, I'm appreciating this feature more and more. Have a look at the picture to the right; it's a snapshot of the 3-hour status screen on my pump (click on the picture for a full-sized version). Pressing the ESC key once will access this screen. When the screen is first accessed, the most recent BG value will display; pressing the up and down arrow buttons will scroll through every BG value that was recorded (in five minute increments) for the last three hours. As in the picture, the value will be highlighted and titled "History". The line graph to the left represents dots for each and every BG occurrence; horizontal dotted lines are low and high BG thresholds, and the small bar below the low threshold line represents a bolus (a correction in my case). When you access the menu without going into the history, the current BG value will sometimes display arrows representing trends. One arrow up or down, and BG values are changing by 1.2-2.2 mmol per 20 minutes; two arrows and BG levels are rising or lowering at a rate of more than 2.2 mmol per 20 minutes. Big BIG value in this one. I can tell whether I need to correct or temp up a basal by these arrows. If one arrow is pointing up, I temp a basal. If two arrows are pointing up, I correct. One down, I temp. Two down, I pop some glucose tabs. (These depend on where the BG value is within my target range, of course) So much easier to triage this way!

The 24-hour screen looks similar to the 3-hour screen, but it displays BG values for the last 24 hours, in 20 minute increments. Picture to the left this time. It also displays the most recent BG value and has a charting of all BG values over the last 24 hours.  The shaded area represents the 12 hours from 6 pm to 6 am; the light area is the hours from 6 am to 6 pm.

The pump allows you to set high and low thresholds, and if your BG goes over or under that number the pump will alarm. I experienced this feature several times on Friday night while I was sleeping. Turns out I dumped during the night; though I woke myself the first time (shakes and all) I would've slept through the second hypo episode at about 4 am had the siren not woken me (and my dog). Yikes! Instinct tells me that the first episode was an aberration, but I'm not sure about the second. A few more nights and I should know. The pump has unique alarms for high and low BG levels. You all know the standard Paradigm beep BEEP beep? Well, they got crafty with these ones (haha). The low alarm is a most amazing beep beep Beep Beep, with each beep ascending in tone. The high alarm is the polar opposite: Beep Beep beep beep, each beep a lower tone than the last. If you don't answer the alarm within fifteen minutes, off goes the siren. And in that case, it's a great thing to be woken up.

Now, we've all been told that these sensors are only good for three days. Well, that's not true. My pump trainer wears hers for six. She also told me of a guy out East who wears his for nine. I'm shooting for ten ;) The sensor will automatically expire after 72 hours; however, this doesn't mean you have to insert another one. Although I haven't yet tried this myself, my trainer has told me that all you have to do is pretend you inserted a new one and tell the pump that. It doesn't know any better. Bing bang boom, you're good for another 72. Suddenly that $475 box of sensors lasts you two months, not one. Barring any Bad Sensor errors, of course. The trick, I've been told, is to tape tape tape. The sensor needs to be anchored against any sort of movement, and it is possible - and feasible - to wear it for another three days. She also assured me that she hasn't seen any decline in accuracy after extended wear. I'll let you know how that goes.

Other than all that, I am in love. I've attached a few extra pictures for fun. Enjoy!

Sensor/Transmitter:

Old 'Purple' 515:

New 'Smoke' 522 (complete with Thinset Reservoir):

Getting Ready for the Paradigm REAL Time 522 Insulin Pump

   In anticipation of getting the Paradigm 522 Real Time System within the next couple of weeks, I've been boning up on the technical information for the pump/sensor/transmitter, as well as preparing my own diabetes management for the big change.

   What does this mean? Well, I'm going to be doing some major testing during the next two weeks to establish the most consistent ratios possible. Granted, I'm enough of a control-freak that I test ratios monthly. Basal rates, CHO ratios, correction ratios (ISF), and bolus patterns are all a part of this monthly routine. Chances are that testing them again - I plan to do at least three of each, while I usually only do two - will not result in any huge change, but I want a baseline so that I can evaluate the efficacy of using the Real Time System. For this reason, I've also ordered a home A1c kit, though I don't expect to see much of a deviation from my last results of 6.2%.

   I also want to truly see, in black and white, if my average of 12 manual BG tests per day is really missing The Big Picture.

   But I won't bore you with those details...

   I also want to know as much as I can beforehand about how the transmitter/sensor system works. So I sent an email to Medtronic of Canada asking for some sort of technical information. The brochures and informational packages on Minimed's website are disappointingly lacking in details about this new system - it's all "how great is this" and "get better control" and blah blah blah. Meat, people. We need some meat on this thing. Now, if you're a Canadian and you have a Minimed pump, then I'm sure you have, at some point, called or emailed the customer service line and spoken to Rachelle (whom I like to call my 'contact'). And I'm sure that it won't surprise you that she came through on my request, as she has for the past three years. She emailed PDF copies of the user guides for both the 522/722 and the sensor/transmitter. Oh, and she's sending me some free samples of the Sure-T Infusion set...but that is better kept for another post.

   I'm not going to post the documentation that Rachelle provided me with, but I will do my best to summarize the salient points - in no particular order, of course! I'm not going to go into much technical detail of the actual pump, as it is the same pump as the 515/715, but will focus more on the transmitter and sensor applications and how they pertain to the operation of the pump.

Paradigm REAL Time Transmitter/Sensor Specifications & Features:

• Blood Glucose Threshold:   2.2 mmol - 22.2 mmol (40 mg - 400 mg) *Like your glucometer, the Sensor is limited to values it can read accurately. For example, the results range of the Freestyle Mini (Flash) is 1.1 mmol - 27.8 mmol (20 mg - 500 mg) and any values below or above this will not display as a number, but as "HI" and "LO".
• The sensor can be worn for 72 hours and MUST be calibrated twice a day (every 12 hours). More frequent calibration (4 x daily) means more accurate BG results. The status screen on the pump displays the remaining life of the sensor being worn, and an alarm will sound when the sensor is no longer any good.
• The Sensor measures interstitial fluid. Glucometers measure whole blood or plasma, and scientific studies indicate that interstitial fluid and whole blood/plasma concentrations, while not identical, are very close with the exception of rapid blood glucose level changes. Plasma/whole blood reflects these changes more accurately, while interstitial fluid lags slightly and can cause a few minutes delay in accurate readings.
• Once the sensor is inserted it takes 2 hours to initialize. That means that, for the first two hours, there are no BG levels being recorded. After the initialization, a manual BG must be taken with a glucometer, and then entered into the pump to be used as calibration for the sensor.
• The sensors MUST be refrigerated prior to use, and then left - unopened - at room temperature for five minutes before insertion. Yep, I know, that's a big drawback on this one.
• The sensor and 522/722 pump have alarms for everything, the following few being related to the sensor:
  • High Glucose - a user preset BG level. When the sensor detects a reading at or above this level, an alarm will sound and continue every five minutes until the sensor reading is below the set threshold. Alternately, there is a high glucose snooze function, much like on your alarm clocks at home.
  • Low Glucose - works just like the High Glucose alarm, except the threshold is a low number. Also has a low snooze function.
  • Meter BG Now Alarm - alarms every 5 minutes, when the sensor requires calibration. There is also a snooze option.
  • Cal Reminder - an optional alarm to remind to enter a manual BG for sensor calibration, above and beyond the BG Now Alarm.
• The sensor can be inserted either manually or using the Sen-Serter. It is inserted subcutaneously, into the fatty layer under the skin, at a 45 degree angle.
• The transmitter cannot be connected to a sensor site that is bleeding (bad, very bad). Minimed suggests waiting five minutes after sensor insertion before connecting the transmitter, to ensure that the site is not bleeding.
• Alternate testing sites are not supposed to be used for sensor calibration. Fingertips should always be used when calibrating the system.
• The status screen allows users to view graphs, current glucose levels, three hours of data and 24 hours. Arrow(s) next to the current glucose level show blood glucose trends; whether they are dropping or rising. One arrow up or down means BG has changed by 1.2-2.2 mmol in the last twenty minutes (relative to arrow direction). Two arrows up or down shows a change of more than 2.2 mmol over the last twenty minutes.
• It is possible to bathe, swim and shower with the transmitter and sensor. However, Minimed gives direction that both parts of the system are to be covered by an occlusive dressing (IV3000) and submersion in hot water should be avoided.

   Medtronic included a whole section in the user's guide that touches on the accuracy of the system and the results of clinical studies. I prefer to leave this kind of thing to individual research or a different post...so I won't be touching on it here, except to say that yes, the system obviously can be improved. And Medtronic themselves state that immediate therapy/treatment changes should not be made based on only the Guardian results; they should be confirmed with a manual BG test. Especially hypo/hyper episodes. But this is only the first in what is sure to be the next big deal for diabetes care.

   As for the rest, well, I'm going to leave that to my own experiences. Good or bad.

   In the meantime, have a look at this CGMS Comparison Chart. Looks like the Navigator is soon (and finally) to be another option - I've been watching and waiting forever on this one! (big Freestyle Fan here)