With an "insulin pump", the pump does not know how much sugar is in
the blood, unless you do the "finger stick" test, and program the
pump. In order to prevent hypogylcemic (low blood sugar) reactions,
this test must be performed as often as 10 times day. This is called
an "open loop" system, because the pump just runs constantly, at a
rate set by the wearer.
The"artifial pancreas" contains an insulin pump, AND a glucose sensor
AND a microcomputer. The microcomputer reads the sensor to see how
much sugar is in the blood, then tells the insulin pump exaclty how
much insulin to send. With the computer/sensor controlling the
amount of insulin, this is called a "closed loop" system.
Up until now, part of the problem has been a suitable, implantable
glucose sensor. Previous sensors could only be used one time -- like
the finger stick meter inserts. This new sensor is somehow "reusable"
-- apparently self-cleaning. It is inserted under the skin, with what
I presume is a very simple surgical procedure. But I've hear of a
sensor being developed in Japan that is based on a needle.
Until we can invent a device that will MAKE the insulin itself
(instead of having to be refilled every day), this is as close as we
can get to "artificial pancreas"
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