Thanks to Amy Tenderich for the heads up!
This just out from Diabetes Health magazine: http://tinyurl.com/5dvstc
Pretty cool!
Thanks to Amy Tenderich for the heads up!
This just out from Diabetes Health magazine: http://tinyurl.com/5dvstc
Pretty cool!
Thanks, Manny! This chart is great, though it’s out-of-date in respect to the Freestyle Navigator and has some incorrect info (like it takes 2 AA batteries, not 3, etc.). This page at Children with Diabetes is a little more accurate:
This has pretty out-dated info on the Dexcom.
I think the most important update for the Dexcom is that it will now accept manual input for calibration, meaning it can calibrate with ANY meter.
Thanks for providing this resource, Manny.
Whoops, I just noticed I wrote that wrong. The Nav takes 2 AAA batteries, not AA. Replaced them yesterday for the first time.
Permalink Reply by David Yolleck on January 14, 2009 at 9:03am
Actually, I think the JDRF study showed a .5% glycated hemoglobin decrease in association with CGM therapy. That improvement would not, in my humble opinion, clinch the case favoring use of CGMs. I think it most likely that such modest improvement could be replicated, if not improved upon, by increasing frequency of conventional finger-stick tests.
Amongst other problems,I find the ‘real time’ characterization of CGM glucose values to be off the mark. There are no clear algorithms by which to convert interstitial glucose values into pasma glucose values. The relationships, as a matter of physiology, are highly variable. It is not even the case that plasma values clearly lead interstitial glucose values – as in the case of vigorous exercise. These unclear relationships are exacerbated byimperfect CGM measurements especially in the presence of glycemic fluctuations. One should not rely on CGM values as a basis for interventions as such reliance could give rise to lethal consequences. I am especially skeptical about use of CGM as basis for a closed-loop system of insulin delivery (except, perhaps, for the most minimal closures of the loMELISSA,HOW WOULD U HANDLE THIS OBJECTION. INTERVIEW COMING UP. HELP. JMI DEVLIN
While most of the time my CGMS is pretty close–I WOULD NOT advocate or support its use for a closed loop system–if you have a raging high (illness) it does not calculate a good correction and it is slow to recover after lows (it is good at catching them for me–THE reason I use it) I do like the trending–as I am very labile–it is helpful to know which way you are headed without 2 sticks (you can do an aklternate site and a finger stick to get an idea–but only gives two points–not the best but…)
“Slow to recover after lows”. I was led to think with the CGM I would let me avoid the lows. Isn’t that the purpose.
I agree with Denise. Interstitial monitoring is not yet (and I personally don’t believe will ever be) ready for a closed loop system.
How you handle that objection from insurance is that you will continue to use blood glucose monitoring for more than just calibration. All your dosaging and care decisions will still be made on the basis of blood glucose values, not your interstitial readings. It’s the insurance not seeing how this as a viable replacement for blood glucose testing that is the problem. I still test my blood sugar upon waking, before bed, and before and after meals. I don’t pretend that it’s a substitute for the finger prick.
Interstitial monitoring is a tool with two purposes that blood glucose testing alone CANNOT achieve. First, it is a trending tool able to help diabetics recognize otherwise invisible trends in their daily glucose patterns. I can see reliable data post-meal or during specific basal insulin activity that allows me to adjust my dosage decisions. I have full knowledge of the extreme peaks on either end of my glucose control - whereas I would have to “catch” the highest or lowest sugar in the day on my glucometer - an impossible feat. Over time, I can make significant decisions about my care based on what I see in these patterns. I might not have known that I am experiencing a spike around 3 or 4am or that I need to make adjustments to my basal insulin.
Secondly, and why so many of us long for a CGMS, it can alert me to rapid changes in my glucose levels before I reach either extreme. This alone can have a positive outcome on both my A1c values and my standard deviation in glucose values. I have lowered my standard deviation from 60-70 to 30 mg/dL since I started the system in November, though my A1c has stayed constant at 6.1% (checked in October pre-CGMS and again in February post-CGMS). That means that my body spends less time away from the same average blood sugar. Or, in other words, I may have been averaging 125 before the CGMS, but I was spending time in the 40s and the 200s equally to achieve it. Now I range between the 70s and the 170s or so and that means less insulin reactions and less wear and tear on my organs. The predictive technology associated with the system predicts highs and lows based on the RATE of CHANGE in your glucose - the actual value matters little to me! I want to know that if my blood sugar is 100, I am stable at 100, not dropping or rising. Blood glucose values alone cannot tell me this without testing every few minutes. This knowledge of my rate of change allows me to make better decisions about my dosages or my dietary needs as well. If I’m 100 but dropping quickly, I will want to take less insulin or eat something extra. If I’m 100 and stable, I might not make that same choice.
Very, very excellent reply. Thank you very much
Dear Melissa.
You have discovered the derivative (i.e. rate of change) unit of control theory. The other two are proportional and integral. the combo is called PID and forms the backbone of classical industrial and military automatic controllers. that is intersting that the derivative can be reasonably accurate without the absolute value being so.