Omama, everyone has given you great advice. I offer prayers and hugs that everything will work out for the best with the cold situation for your son and daughter, and that his surgery will be successful. I know how freaked out I would be if one of my kids got a cold/sick right before surgery. Can you give your kids probiotics and immune boosting vitamins/herbs, like Airborne?
My son has stayed at St. Joe's PICU in Phx twice for heart surgery. It's been over 2 years since his last surgery so things may have changed, but I'll share my experience: They provided me a hospital grade pump on wheels in his room and a pumping kit, as well as bottles, caps, etc. I was able to sleep in his room every night on the padded bench, which is better than some hospitals, but still not very comfortable. They provided sheets/pillows/blankets, but I also brought my own pillow/blanket from home. I got 3 meals/day as a nursing mama, which I totally appreciated because I never wanted to leave the room. The really nice thing about the PICU rooms is that they each have a private bathroom with a shower...this is a total luxury! Will your ds get discharged straight out of the PICU or will he be transferred to the general peds floor? The general peds floor is totally different than the PICU, so be prepared. Not as nice, and nurses are not able to be as attentive because they have so many patients. They do have a pumping room though, and a room with computers for internet access on the general peds floor. Like I said, this may have all changed because it's been awhile, but hopefully this info will help you.
Good luck! Hugs!