Hi Rachel,
That’s a double whammy of unfortunate circumstances. The matter of which surgery goes first will depend on how each problem is affecting your dog. If the gallbladder stones are causing an obstruction, that could be more life-threatening as the pyometra is open and draining. If the stones aren’t causing an obstruction, the pyometra may be dealt with first to avoid further infecting the body. Your veterinarian will have to guide you on those decisions based on your pet’s clinical status.
I hope this helps.
Dr. Ryan Llera