Flying & Blood Sugars

With all the travel I did in the past two weeks my blood sugars turned into an utter mess.  What I have noticed is that it seems everytime I fly my blood sugars get totally out of whack (whether I change time zones or not).  Car trips greater than 4 hours also tend to elevate my blood sugars but to a lower degree than flying does.  When I fly I make sure that I eat as healthy as possible and try to drink as much water as possible.  However, the pressure changes in altitude can change the digestion process and flying dehydrates you in general.  I haven't yet figured out a way to counterbalance the metabolic effects of flying for blood sugar management; it would be nice to not have blood sugars of 400 everytime I fly though!