3 The procedure
3.1 Transanal total mesorectal excision (TaTME) aims to improve the clinical outcome of rectal excision, and to reduce the length of stay in hospital and morbidity after surgery. It may facilitate proctectomy that would be difficult by an open or laparoscopic approach in people with a narrow pelvis or high body mass index, or where the position of the tumour is low in the rectum.
3.2 Before surgery, the patient has bowel preparation and prophylactic antibiotics. With the patient under general anaesthesia and in the lithotomy position, standard laparoscopic mobilisation of the left colon and upper rectum is performed. After insertion of an operating platform into the anus, the lower rectum including the total mesorectum is mobilised in a reversed way using standard laparoscopic instruments.
3.3 The transanal part of this procedure starts with insertion of a purse‑string suture to close the rectal lumen, followed by a full thickness rectotomy. After identification of the total mesorectal excision (TME) plane, the dissection progresses proximally until connection is made with the dissection from above. The specimen can be removed through the transanal platform or, if the tumour is large, through the abdomen using a small incision. Anastomosis to connect the colon and the anus can be done using sutures (hand‑sewn technique) or staples. When anastomosis is not possible, the patient is given a permanent stoma. When an anastomosis is done, a temporary ileostomy is usually created.