ANATOMY
Superior hypogastric plexus (sympathetic)
Left and right hypogastric nerves (on rectum between fascia propria (thin facial envelope around mesorectum) and endopelvic fascia) These join pelvic parasympathetics to form inferior hypogastric plexus on pelvic side wall. Branches pass to rectum in lat ligs and rest go to bladder and sexual organs
Denonvilliers fascia is the regressed peritoneal reflection which extends to the pelvic floor in early development
Described 1836
Fusion of retrovesical cul-de-sac
glistening white trapezoid apron
Laterally close to neurovascular bundle
Visible on MRI
?dissect in front- (Heald) but higher risk nerve damage therefore only if anterior tumour
Lateral ligaments are not true ligaments but condensations of connective tissue containing middle rectal aa
High=above peritoneal reflection, low=below
Tumours rarely spread distally, so traditional margin is 2cm, but 1cm is accepted for T1 and T2 tumours
PROCEDURE
Aim:
Avoid local recurrence: tumour disruption, inadequate excision, implantation
Avoid patient morbidity: Bowel function, sexual. bladder
Lloyd-Davies and Yellow-fin boots
Trendelenburg
Prepare the abdomen and drape using Mayo stand covers for the legs, three large and two small drapes for the groin and perineum to shut them away, while allowing access for anastomosis. Use an Ioban drape.
Ensure an ileostomy is marked pre-operatively.
Book Walter
St Marks
Head light
IDC
Midline incision
General laparotomy
Check tumour resectable
Identify left ureter and gonadal (gonadal will be lateral)Lies in posterior wall of intersigmoid recess where crosses left CI
Mobilise left colon to splenic flexure: aim to make it a midline structure.
Operator stands on the patients left and assistant on the right. The assistant elevates the sigmoid colon vertically. Operator using Debakey forceps & diathermy mobilises the peritoneal reflection. Work over a wide front. Stay more on the mesentery side than the lateral wall, retroperitoneal tissue side. Identify the gonadal vessels, the ureter is medial to these and also should be identified.
Score the peritoneum on its medial aspect again over a wide length. Then create a window, the ureter needs to be posterior. The resistance anterior will be the vascular pedicle. Next create a second window by looping the index finger from medial around the base of the IMA, thin down the tissue and diathermy onto my finger tip. Thin out the pedicle then double clamp and divide and tie it with 0 Vicryl.
Continuing along the posterior aspect of the colonic mesentery superiorly you will come to the IMV. Again score the mesentery with diathermy (or scissors) and with the hooking finger use diathermy to create another window. Divide this if you need more length (making a colopouch)
Splenic Flexure
Dual approach via the left paracolic gutter and by taking the greater omentum off the transverse colon. Moving between the legs makes this easier. The assistant lifts up vertically the greater omentum. Use diathermy to divide along the plane of fusion between the greater omentum and the transverse colon appendices epiploica. Mobilise further by insinuating the left index finger behind the greater omentum and with the thumb rolling the colon inferiorly then diathermy onto the radial border of your index finger. (A fixed retractor assits in lifting up the abdo wall to expose the left upper quadrant, especially useful if the assistant is not strong).
Note that the tissue above and adherent to the transverse colon can be diathermied.
Take care not to damage the spleen, divide any omental adhesions to it.
High ligation: must avoid superior hypogastric plexus over aorta
Identify the IMV at the inferior border of the pancreas and ligate it above a vein coming down from the splenic flexure. This ensures adequate length of the colon to reach down to the pelvis (see figure above)
Sequentially ligate any vessels including the main trunk of the left colic artery (leaving the upper and lower branches intact so as to re-inforce a deficient Marginal artery at the splenic flexure) and the Marginal artery. Test the Marginal artery for active bleeding prior to ligation.
Enter presacral space with sharp dissection, anterior to presacral fascia. Sweep hypogastrics (just outside this layer) backwards. Extend to coccyx
TME
Define presacral space.
This is aided by pulling upwards on the rectum and the placing the lipped St Mark’s retractor over it a lifting upwards to gain additional traction. This places the tissue on tension and aids with defining the areolar plane.
Work around the back then dissect to the sides using diathermy. The key is to keep the tissue under tension. Anteriorly divide several millimetres inferior along the rectovesical fold. Preserve the seminal vesicles, dissect deep to them.
Rectosigmoid reflected anteriorly and posterior avascular plane developed using sharp dissection or diathermy under vision
Blobbed lipoma should be demonstrated
Posterior dissection first, then lateral, then anterior
Do not finger hook or clamp lateral ligaments
Incise lateral peritoneum and meet at anterior cul de sac
Anterior plane to dissect is between denonvilliers fascia and fascia propria (mesorectal plane) if too anterior risk nerve damage (this is the most likely area)
Dont stray laterally to avoid pelvic plexus damage
Use diathermy laterally (insignificant vessels)
Ideally 5cm distal clearance
Cross clamp with stapler
Rectal washout
Place the anvil of a CEEA 28mm (31mm in males) stapler in the proximal end of the divided colon and secure with a 4/0 PDS pursestring. This can also be done through an enterotomy in a fashioned colon J-pouch for ULAR.
For HAR, a complete TME may not be required but principles are the same.
For HAR/LAR/ULAR, place a right angled clamp proximal to the distal resection margin and perform a lavage of the rectal stump using diluted betadine solution.
Divide the distal end of the specimen using a (TA60/PI55/Roticulator 55 with 3.5mm staples) stapler distal to your previously placed right angled clamp. Deliver the specimen to the scrub nurse (or as MT says send the shit to the Pathologist!).
For a Hartmanns resection, oversew the distal end using 4/0 PDS leaving the end sutures long for later identification if it cannot be brought up as a mucous fistula. Fashion an end colostomy in the LIF (matured with 3/0 chromic gut). The splenic flexure may not necessarily have been mobilized, however a reversal operation in due course will be easier
Place the CEEA 28mm (or 31mm in males) staple gun in the rectum and advance the spike through the stump just adjacent to the staple line.
Perform the anastomosis ensuring that there is correct alignment with no tension. Remove the stapler and reinforce the anastomosis with inverting Lembert sutures if necessary.
Lavage the abdominal cavity with water and perform an air leak test. Place a suction drain in the pelvis posterior to the anastomosis.
For a Loop ileostomy, select a suitable position on the terminal ileum and make a small window at the mesenteric border to pass a Nelaton catheter to hold the loop. Place orientating sutures (short-small, long-large) of 4/0 PDS
Perform the stoma trephine with a pack against the inner surface of the abdominal wall and make a cruciate incision in the anterior layer of the rectus sheath, split NOT divide the rectus muscle and a vertical incision in the peritoneum (ensuring adequate tension on the muscle and skin with applied Morrisons forceps). Insert a Fraser forcep through this incision into the abdominal cavity.
Bring the loop of terminal ileum out through the stoma trephine in its correct orientation and close the abdominal wall, skin and apply a dressing.
With the wound sealed, mature the loop ileostomy with 3/0 CG. Excise the redundant length of the Nelaton catheter and suture it to skin as a securing rod.
Apply a stomal appliance.
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