Recently I started recommending a saline enema the night before and the day of robotic surgery. I have not done that for the past several years and I don’t consider it to be a must, but it is nice not having to fight with a colon full of stool.
One case where the sigmoid colon can definitely be in the way is the left infant ureteroureterostomy:
The following patient had 2 saline enemas before bilateral ureteral reimplantation; see how much room there is in the pelvis: