[Previous Months][Date Index][Thread Index][Join - Register][Login]
[Message Prev][Message Next][Thread Prev][Thread Next]

[IP] How to Avoid Bubbles

I haven't had any problems with bubbles in the infusion set tubing, but I 
can certainly understand how they could happen. Here's what I do to avoid 
them (using a Minimed 507C with a 3 ml reservoir). Of course, as in all 
things diabetic, YMMV:

First of all, bubbles aren't magic. They're present because either they 
were _pushed_ into the tubing (from trapped air) or _pulled_ into the 
tubing (from a loose fitting).

1. Before filling the reservoir, pull (not all the way) and push on the 
plunger a couple of times to distribute the lubricant already inside. This 
will reduce the possibility of air leaks around the plunger while filling 
the reservoir in step 4.

2. Before filling the reservoir, twist the filling needle with the plastic 
cover so it's *tight*. This will minimize air leaks through the needle in 
step 4.

3. Withdraw the plunger to fill the reservoir with air and then inject this 
air into the insulin bottle. If this step is omitted, the insulin bottle 
will be under a vacuum and air will be sucked into the reservoir from 
around the plunger in the next step.

4. Fill the reservoir from the insulin bottle with the needle pointed *up* 
so that air floats to the top of the reservoir. When the reservoir is full, 
withdraw it from the insulin bottle. Holding the needle *up*, tap sharply 
on the reservoir so that the air around the plunger is knocked to the top. 
Then, hold the reservoir up to a bright light and push the air (and any 
insulin trapped between air pockets) out of the reservoir. Stop pushing on 
the plunger when insulin starts to flow out the needle and no bubbles are 
left in the reservoir.

This step is NOT included in the "Instruction for Use" of the Minimed 3.0 
ml Reservoir (REF MMT-103). Instead, Mimimed advises you to get rid of the 
air after you connect the infusion set (step 6). However, it's much easier 
to manipulate the reservoir without the infusion set attached and I haven't 
yet filled a reservoir without seeing some air at this point. IMHO, this is 
the single most important step listed for eliminating bubbles.

5. Holding the reservoir with the luer connection *up*, unscrew the (tight) 
needle with the plastic cover, and attach the new infusion set connector. 
Screw it on *tight*.

6. Holding the reservoir with the luer connection *up*, push on the plunger 
until the insulin comes out the needle. Once insulin starts coming out, 
there should be no bubbles visible anywhere at this point. If you see 
bubbles, get rid of them before going any further. Try to figure out how 
they got there. THERE IS A REASON.

7. Insert the plunger into the pump and (gently) push the driver arms 
against the plunger to minimize the priming quantity.

8. Prime the pump. 5 units should be more than sufficient. If insulin 
doesn't appear at the needle tip after 5 units, look for leaks and bubbles 
and try to figure out what went wrong. THERE IS A REASON.

Any suggestions for improving this procedure would be appreciated. 
for HELP or to subscribe/unsubscribe, contact: HELP@insulin-pumpers.org
send a DONATION http://www.Insulin-Pumpers.org/donate.shtml