Re: [IP] Cozmo cartridge filling probs...bubbles?
>Has anybody had any problems filling cartridges? My daughter is often
>frustrated with having too many bubbles. Does anybody else have this
>problem? Does anybody have any tricks or know the reason? She can't seem
>to figure out why it happens sometimes and other times it doesn't happen.
1. Don't shake, rattle or roll the insulin bottle.
2. Make sure the insulin bottle is at room temperature. (Gasses
dissolve in cold liquids and form bubbles when they warm up--like
3. When filling, draw back the plunger, insert the needle and inject
air with the bottle on the bottom. Then invert the whole system
(without shaking) and allow the air pressure in the bottle to push
insulin into the cartridge. When the plunger stops moving, tap and
gently wiggle the cartridge (now below the vial) until all visible
air is in the neck of the cartridge, and then push gently on the
plunger to expel the air bubble into the vial. Pull down gently on
the plunger to finish filling the cartridge. Make this a slow
process--too much negative pressure in the cartridge can nucleate new
bubbles and the idea is to have (if any) one large bubble in the neck
of the cartridge. If you can keep cartridge and vial balanced with
the cartridge on the bottom leave them connected; otherwise remove
the needle at this stage.
4. Let the cartridge sit, neck up, while you are rewinding the pump,
getting out the new set, etc. Tap it gently now and then to
encourage any air at all to move up to the neck of the cartridge.I
If you can do it without agitating the cartridge too much, carry the
cartridge upright close to your body to warm it and get the last
dissolved gasses out of solution. (I generally don't have time for
5. Attach the new set tubing to the cartridge. You can prime
manually and then remove the plunger and put the cartridge into the
pump, but I just put it into the pump and let the manual prime fill
the tubing. In either case, keep the cartridge upright. This means
orienting the pump so that the neck of the cartridge stays on top
until the pump is putting insulin out the needle.
Nothing will completely eliminate bubbles, but this helps.
Sue Ann Bowling, North Pole, Alaska
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