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Re: [IP] To be or not to be
On 1 Dec 98 at 11:33, Aaron Michelson wrote:
> This is a thinking person's question. These are authentic questions
> and are not meant to shake the foundations of insulin pump therapy.
> I've been reading and contributing to this list for about 25 hours while I
> wait to see how much the pump will cost me.
Gosh, you must be a quick study... and somehow I sense an agenda somewhere in
the text here...
> There are three benefits to wearing a pump:
> 1. Flexibility
> 2. Accuracy
> 3. Predictability of insulin peaking
> 1.non-pump Flexibility:
> I have two shots of Ultralentin per day.
> I take 8 in the morning and 12 in the evening.
> Then I use a Nono-pen with humalog when I eat.
> This therapy is known as the "poor man's pump".
> It is like the pump with two basal settings that
> cannot be changed on the fly. The novo-pen
> must be programmed for each bolus and is very discreet.
It's also difficult to manage and my experience was that you couldn't vary meal
times by over one-half hour in either direction. They were set by the timing
of your shots of Ultralente. The Ultralente is the controlling factor which
required you to use a twelve-hour prediction factor... It was also more like a
one-size fits all with no way to handle the dawn effect without getting up at
three a.m. to take another shot. After several years of this therapy I was
taking six to eight shots a day and still having problems with unpredictable
highs and lows... Of course I was only on it for about twelve years...
> 2.non-pump Accuracy:
> The accuracy of a 30cc syringe used without carful precision
> is +/- 0.2cc or 2% for doses between 8 and 12 cc. The novo-pen is similar. The
> syringe accuracy can be improved if care is taken and/or a magnifing glass is
And some of it leaks back out when you remove the needle... so the accuracy can
vary considerably... and you forgot about the band-aids for the needles. I've
ruined many shirts from injection sites in my arms or stomach...
> 3.non-pump Predictability of insulin peaking:
> Ultralentin is designed for no peak with effect begining
> in three hours and continuing until the 15th hour.
Designed for and actually having are the problems here - U does have a
pronounced peak at around 7 to 8 hours. Problem is that the onset varies
between 5 and 10 hours - and you'd better have either a pre-programmed life to
handle the schedule or a big box of sugar tabs handy.
> Now my question:
> How is the pump better?
It works - you can set your basal rates to match your actual requirements. You
can vary those basal rates as needed to match your activity level. You can
bolus very discretely in very small increments - try to get that 1/10th unit in
a syringe or pen injection device.
> Is it only as follows:
> I can set more than two basal rates.
> I can change the basal rate on the semi-fly.
> I cannot include accuracy as a pump forte because
> while the pump ejects at a greater than 2% accuracy
> other factors affect the amount injected.
Non-sequitor here - accuracy is part of the "pump forte" because it works. You
cannot include accuracy with a needle either because you cannot control
absorption rates, backflow leakage and burrs on the needle...
. For instance
> if I take 8 units in 12 hours basal then in one hour I get
> 6 pulses. If I remove the pump for any reason for any
> length of time there is a chance of missing a pulse with
> a 17% error that hour. That error spread out over three hours
> is 5.5%. Many pumpers wait until the transfusion site absorption
> becomes a problem before changing the site this causes
> a huge accuracy error. And finaly it is not benefit to go
> from 2% accuracy to 0.02% accuracy.
Sounds like you need to go into politics because these statistics don't
apply... a missed pulse "error" cannot be spread over three hours - it is a
missed event and not a statistical probability. If you remove the pump you
"pre" or "post" load by taking a small bolus... Also if you use the Disetronic
the stats are different because of the difference in the way it delivers the
insulin. Missing a pulse isn't a 17% error - it's a missed event that should
either be corrected for or ignored. Ignoring a 1/10 unit pulse doesn't cause
that big of an effect. Removing the pump for a few hours does, and people have
developed strategies to handle these events...
> I cannot include Predictability of insulin peaking as a pump forte because
> There are unpredictable factors that effect insulin sensitivity. There are
> unknowns about insulin absorption rate and sensitivity fluctuations that make
> a scientific analysis impossible.
So you'd rather go with multiple unknowns instead of a single variable? You
can have a wildly variable absorption curve on U, another one on N and yet
another one for R or H. You can mix and match so you get an error bar that is
says "there's a curve somewhere, we're not sure where, but it's there..." or
you can deal with the single absorption rate of a single type of insulin for a
It looks like you are trying to build some kind of pseudo-medical/technical
case against the pump. Don't waste your time on it. If you are happy with
what your are doing and are one of the .1% of people with diabetes who can
maintain perfect control and maintain flexibility with six shots a day go for
it... just don't try to build a case against those of us who tried it and
found that it just didnt' work. Pump therapy works much better than MDI for
many people. Some people just don't have the ability to manage a pump, while
others have trouble with MDI. My doctor tells me he has patients who have
trouble with taking just 2 shots a day and doing a bg test once a week...
Everybody is different and we each need to have therapy tailored to meet our
needs and our lifestyle. For you, MDI may be the way to go. For many of us
the pump was our last resort - the next step was just to quit bothering with
the six to eight shots a day and quietly sit and let our bodies rot away to the
complications... The questions of flexibilty, accuracy and predictibility are
easily answered - the pump improves all three. Many of us have determined this
by our own experience. The pump also allows you to maintain more stable bg
levels without having to play the "where am I on which curve" minute by
Moral of the story - if you don't like a pump, don't want a pump, or otherwise
have an axe to grind then you really don't have to have a pump. None of us are
going to force one on you. If your doctor is trying to force one on you and
you don't want it we'll defend you as best we can... If you want a pump and
cannot afford one remember that we are all working on putting pressure on
insurance companies and the government to make sure that adequate medical care
is available to everyone. If you want a pump and are ready to get one then we
can pool our experiences and help make your transition easier. If you just
want a sympathetic and understanding ear even if you're not on a pump we can do
that too - and sometimes when the administrators (censors?) aren't watching we
get a laugh or too in edgeways... Maybe that should have read "sensors" as in
"Captain, the sensors are all out of order..."...
Randall P. Winchester
* The views expressed here are mine and do not necessarily *
* reflect the official position of anyone in particular. *
* There's no guarantee on anything said here...
* If I say I understand something completely the only thing
* we can both be assured of is that I must have completely
* misunderstood something.
Insulin-Pumpers website http://www.insulin-pumpers.org/