Foley Catheter insertion into Defunctioning ileostomyTo reduce Postoperative Ileus after Major Colorectal Surgery

Interventions: If randomized to treatment arm a Foley catheter is inserted into the proximal efferent limb of the ileostomy at the end of the operation. The Foley catheter will remain insitu for 5 days post operation. Primary outcome(s): Time taken to tolerate low residue diet without nausea/vomiting. Assessed by clinical observation. Nursing notes and fluid/ bowel charts and patient self reporting. [5 days or until hospital discharge] Study Design: Purpose: Treatment; Allocation: Randomised controlled trial