This is an operation to remove all or part of the rectum and usually part of the sigmoid colon. It is most commonly performed for bowel cancer. It can be performed “open” with an incision in the abdominal wall or laparoscopically, commonly called “key hole surgery”.
After the segment of bowel is removed, along with its blood supply, the two ends of bowel are joined together (anastomosed) with stitches or stapling devices. This requires the anal canal to be preserved, and the bowel upstream to be able to be brought down to join the rectum or anus without compromising the blood supply.
It is uncommon to require a bag or stoma in association with a high anterior resection, which involves removing the upper part of the rectum. If it is required it is usually only when there is technical concern about the anastomosis or there are patient co-morbidities that make an unprotected anastomosis unnecessarily risky.
It is more common to require a bag or stoma in association with a low or very low anterior resection, which involves removing most or all of the rectum. The bag or stoma is usually a loop ileostomy to divert faecal matter from the downstream bowel join.
Anterior resection is a major surgical procedure. The most concerning surgical risk is a leak from the anastomosis, which can occur in between 10-20% of patients especially if the join is “ultra” low and the pelvis has been preoperatively irradiated. It is also attended by the other common surgical risks, such as wound infections as the bowel needs to be opened during the procedure, and medical risks such as heart and lung problems, fluid balance and kidney issues, as well as calf clots (DVT’s) which can travel to the lungs (pulmonary emboli).
Pain relief is well organised after the procedure. Fluids and return to a normal diet are determined by your surgeon’s usual protocol and your individual circumstances.
Your surgeon will discuss the particulars of your surgery with you preoperatively.