The most common reason we have to cancel surgery on the day of the operation is a rash involving the site of the surgical incision. This is usually due to a yeast diaper rash. An active yeast infection inside the diaper will preclude surgery in the area. Yeast infections typically include red spots around the border of a more confluent area of redness. A typical story is that a child receives a course of antibiotics within one week of surgery for an upper respiratory illness and then develops a yeast infection. If your child is given a new prescription of antibiotics just before surgery please let us know, as we may want to treat your child to prevent a yeast infection.