Poor Katie!
The engineering principle of hydrostatics needs to be applied as well by the Inflation Engineer in situations like this.
This is because the pressure buildup in Katie's belly will eventually exceed Katie's ability to inhale, and if inflation proceeds beyond this point, she may actually begin to suffocate before the ultimate stress can be achieved. In fact, it looks like Katie is on the verge of this condition right now. To prevent this from happening to her, positive pressure breathing apparatus should be used, in which the inhalation pressure is adjusted by the inflator to be equal to the belly pressure. In this way, she can breathe comfortably throughout the process.
I have used this technique myself and experienced great success with it. In fact, out of consideration to the inflatee, I personally never apply belly pressure without also furnishing breathing assistance in those cases where the ultimate stress must be measured.
If a plain scuba-type mouthpiece is used to administer respiration assistance, be sure to tie it in place securely with stout rubber straps so it will not blow loose during the inflation.
As an extra bonus, note that if you want, you can use the pressure control on the respirator to conveniently reward her if she is a good girl, or discipline her if she is a bad girl!
Let me know if you would like me to post you some engineering sketches that detail these important principles ;-)
-Latecomer
Nerds! I can't understand any of this! Peace out! =P
I'm a pretty kitty~