Flying and Pressure Changes Effect Insulin Pump

Insulin reservoir with air bubbles
Pictured above, this insulin reservoir has some air bubbles in it. The air bubbles will expand as pressure decreases as a plane ascends, which causes a small amount of insulin to be delivered.
Disclaimer:

This website and blog does not provide medical advice, diagnosis or treatment. Read full disclaimer.

When thinking about taking a vacation and flying on a plane, as someone who uses an insulin pump, there are a lot of things on my mind, but the most concerning one is that insulin pumps may unintentionally deliver too much insulin during take off. There was a scientific study about this and the resulting research paper is available for you to read: Changes in Altitude Cause Unintended Insulin Delivery From Insulin Pumps

That study found that during ascent, “Medtronic pumps delivered 0.709 units excess insulin.” Animas pumps were also studied and they delivered 0.663 units excess during ascent.

This is a small amount of insulin; however, if you are particularly insulin sensitive like myself, then you should be aware of this issue. Personally, 1 unit of insulin can lower my blood glucose by 100 points, so this amount of insulin is enough to cause hypoglycemia.

I disconnected my pump during ascent on my last airplane flight. I disconnected and suspended the pump, and watched as insulin came out of the tubing during ascent. The pump was suspended, so no insulin should have been delivered, but the pressure change caused the air bubbles in the insulin cartridge to expand and push out a small amount of insulin.

This small change in insulin delivery may not have much of an impact on most people who use insulin pumps, but I’m not most people. I’m different. I require only about 20 units of insulin per day and a half a unit of insulin is a normal correction dose for me. An extra 0.7 unit could cause my blood glucose to drop dangerously.

The study also found that less insulin was delivered during descent, so the other possibility is having high blood sugar afterwards from that. I’ve also experienced that.

In summary, I’d say that regulating blood glucose with an insulin pump on a plane is tricky, and I’m personally always going to disconnect during ascent — which is the time from take off until reaching cruising altitude. I’d rather get high blood glucose than go low. Hypoglycemia is more immediately dangerous. High blood glucose can easily be treated. Low blood glucose could make me unconscious.

Related Links

Don’t take my word for this. Read up on this.

Changes in Altitude Cause Unintended Insulin Delivery From Insulin Pumps: Mechanisms and implications

From the flight deck: diabetics, watch your insulin – 2011 Reuters article discussing this research.

Flying With an Insulin Pump

What You Should Know About Flying with an Insulin Pump

Highs when flying and Lows when landing – Tu Diabetes Forum Discussion

IMPORTANT! Update to my previous post about insulin pumps and flying – Tu Diabetes Forum Discussion

Join in on the discussion

What do you do while flying? Has this been a problem for you?

Leave a Reply