LOTS. Pediatric surgeons are in short supply, and there are lots of kids! It is not uncommon for pediatric surgeons in practice to work upwards of 60-80 hours per week. Fortunately they often have assistants which help them out.
Depends. A lot depends on the size of the population that the pediatric surgeon services. Normally if a pediatric surgeon does 400.500 operations a year he is busy.