What would cause the tubing in an infusion set to become like it is “air locked” so that the insulin pump cannot push insulin through the tubing? Even a person cannot push the needle to get insulin to go through the tubing.

This is most likely due to a block at the needle tip insertion point caused by some scar tissue, any random small piece of tissue that lodged there at insertion, and sometimes at the juncture of the plastic catheter to the inserted catheter point. Very low flow rates as well as some local irritation/movement of the catheter insertion site are my clinical guess as to why this occurs. There is not much one can do except to change the catheters more frequently if this recurs. Some folks change insulins, thinking the diluting solutions may be part of the problem. Some also change from one to another brand of catheters to see if this helps.

Some good detective work and problem solving usually decreases or eliminates the problem.

SB