Open anterior resection

Key principles

• Often receive preoperative radiotherapy
• Total mesorectal excision
• Identify and preserve hypogastric nerves to reduce autonomic dysfunction
• Aim 2cm margins distally if low tumour, otherwise standard 5cm
• Consider defunctioning stoma if low or positive leak test

Specific preoperative preparation

• Usually performed for malignancy, ensure complete staging, discussion in MDM and completion of any neoadjuvant treatment
• Preoperative fleet enema x2, rarely need bowel preparation
• Stoma sites marked

Operation Details

• GA. Modified Lloyd Davies position, IDUC, IVAB, SCDs, TEDs
• Rigid sigmoidoscopy and rectal wash
• Stand on patients right
• Prep and drape
• Midline incision. On table retractor. Pack SB away
• Mobilise
  • Mobilise left colon along line of Toldt taking care to identify the left ureter and gonadal vessels
  • Mobilise the splenic flexure
    • Complete the left colonic mobalisation up to the level of the splenic flexure
    • Mobilise the greater omentum off the distal transverse colon
    • Enter the lesser sac and retract the colon caudally
    • Divide the splenocolic ligament
• Ligation
  • IMA
    • Divide peritoneum on right side of sigmoid loop to identify IMA. Ligate at origin taking care to avoid hypogastric nerves and plexus + ureter and gonadals
  • IMV
    • Divide IMV below pancreas
    • Do not have to routinely take but aids with mobility
  • Colon
    • Transect colon and pack remaining colon away
• TME
  • Enter mesorectal plane posteriorly dissecting between parietal and visceral pelvic fascia down to below tumour.
    • Facilitated with St Marks retracting rectum
  • Continue dissection laterally both sides and then anteriorly
  • In males dissect down on Waldeyers fascia overlying SV and prostate to allow adequate mobilisation of tumour. Remove this fascia if anterior tumour. In females dissect between rectum and vagina
• Rectal transection
  • At site of transection divide mesorectum onto rectal wall
  • Divide rectum using Contour stapler
• Anastomosis
  • Size appropriate circular stapler usually 29-33mm and place anvil in colon end using purse- string suture
  • Place stapler transanally and guide it to staple line. Open spike just behind staple line and connect anvil to stapler. Close and fire stapler
  • Check donut integrity and perform leak test
• Washout and close
• Consider diverting ostomy

Intraoperative complications & challenges

• Lack of length o Mobilise splenic flexure and transverse colon. Ensure IMV divided high on pancreas • Bleeding o Splenic – pack, topical agents, splenectomy o Pelvic – pack, apply compression. Typically, due to incorrect plane of dissection. If arterial isolate vessel and clip. If venous typically stops with pressure. If significant vascular injury, inform anaesthetist, nursing staff and obtain vascular set. Get assistance. Isolate vessel and obtain proximal and distal control. Repair with fine non-absorbable suture • Ureteric injury o Identify location, avoid extensive dissection as will damage blood supply o Review imaging, ensure normal contralateral kidney o Seek advice from urologist. Options Primary repair over J-J stent after spatulation with 5/0 monocryl § Reimplantation into bladder if low +/- psoas hitch Uretero-ureterostomy Exteriorisation Nephrectomy

Post-operative complications

• Immediate o Bleeding o Visceral injury o Ureteric injury • Early o Infection o Haematoma • Late o Hernia o Autonomic dysfunction o Local recurrence