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Chapter 12 • Open Abdominal Perineal Resection 225
The patient should be told that the perineum will be numb and that different sensations will
be present. The skin requires at least 2 to 6 weeks to heal completely because of the previous
radiation and the ongoing drainage that frequently occurs because of the deep fat plane with
poor blood supply.
Selected Readings
Dozois EJ, Privitera A, Holubar SD, et al. High sacrectomy for locally recurrent rectal cancer: can long-term survival be achieved? J Surg
Oncol 2011;103:105–9.
D’Souza DN, Pera M, Nelson H, et al. Vaginal reconstruction following resection of primary locally advanced and recurrent colorectal
malignancies. Arch Surg 2003;138:1340–3.
Marr R, Birbeck K, Garvican J, et al. The modern abdominoperineal excision: the next challenge after total mesorectal excision. Ann Surg
2005;242:74–82.
Step 1: Clinical Anatomy
C H A P T E R
13
Laparoscopic Abdominal
Perineal Resection
James W. Fleshman, Jr.
The left colon lies along the left side of the abdomen suspended from the splenic flexure to the
pelvic brim by lateral peritoneal attachments. The mesentery of the left colon arises from the
midline of the abdomen along the aorta. The sigmoid colon has no lateral peritoneal attachments
other than some congenital adhesions, which fix the apex of the sigmoid to the pelvic brim
and the iliac fossa. Otherwise, the sigmoid colon is attached to the retroperitoneum through a
midline mesentery arising from the inferior mesenteric artery (IMA) and extending down into
the pelvis to the mesorectum. The splenic flexure is attached to the undersurface of the tip of
the spleen, the lower edge of the tail of the pancreas, and the anterior surface of the left kidney
by various levels of suspensory ligaments and peritoneal extensions. The blood supply to the
left colon is based on the IMA, which arises from the anterior surface of the aorta just above
the bifurcation of the common iliac arteries. The IMA extends anteriorly and bifurcates to
produce the superior rectal artery feeding the sigmoid colon and the rectum. The left colic artery
extends cephalad to provide the left colon and distal splenic flexure with blood supply through
the arcade at the mesenteric edge known as the marginal artery of Drummond. The retroperitoneum behind the left colon contains the left ureter and the gonadal vessels lying over the
psoas muscle. The ureter crosses the iliac vessels at the bifurcation of the iliac vessels into the
external and internal iliac branches (Figure 13-1).
226
Pancreas
Chapter 13 • Laparoscopic Abdominal Perineal Resection 227
Spleen
Left kidney
Transverse
colon
Splenic
flexure
Duodenum
Figure 13-1
IMV
IMA
Left ureter
Left colon
228 Chapter 13 • Laparoscopic Abdominal Perineal Resection
Pelvic Anatomy
The pelvic anatomy is complex and has interrelationships between the rectum, vagina, uterus,
ovaries, bladder, and prostate. The anatomy is important for pelvic dissection because of the
various structures that are at risk, such as the splanchnic nerves, innervating the bladder, the
ureters, and the organs themselves. The anatomy begins at the pelvic brim right at the sacral
promontory. The common iliac artery and vein on each side course along the posterior aspect
of the pelvic brim. The hypogastric plexus of parasympathetic and sympathetic nerves is found
between the bifurcation of the aorta and common iliacs. This plexus coalesces to the right and
left as the splanchnic pelvic nerves, which run along the inner aspect of the pelvic side wall to
the level of the obturator fossa and the anterolateral ligaments carrying the middle hemorrhoidal
vessels. Nerve fibers course from the splanchnic nerve to the rectum through the anterolateral
ligaments along the middle hemorrhoidal vessels. Extension of these nerves continues to either
the vagina or the prostate as the nervi erigentes. A clear understanding of this nerve anatomy
is crucial because it is easily damaged during dissection and results in both sexual dysfunction
and urinary bladder dysfunction (Figure 13-2A).
At the level of the sacral promontory, an areolar tissue plane begins behind the superior
hemorrhoidal artery. The superior hemorrhoidal artery descends from the bifurcation of the
IMA and splits at approximately S1-2 to give two major trunks down the posterior aspect of
the rectum. The mesorectal envelope encases the fat and lymphatic and vascular structures to
the rectum. The areolar tissue plane outside the mesorectal envelope is known as the “holy
plane” and guides the dissection in the pelvis. A cross-sectional diagram of the pelvis shows the
visceral peritoneum encasing the mesorectum with the areolar tissue plane between the visceral
peritoneum and the parietal peritoneum posteriorly. The parietal peritoneum covers a nerve
and venous plexus over the sacrum and the musculature of the side wall of the pelvis. Maintaining dissection within the areolar tissue plane between the parietal and the visceral peritoneal
layers protects all of the crucial structures in the pelvis (Figure 13-2B).
Chapter 13 • Laparoscopic Abdominal Perineal Resection 229
Inferior
mesenteric
plexus
Hypogastric
nerve
Nervi erigentes
Presacral (Waldeyer’s fascia)
Fascia propria of rectum
Lateral ligament of rectum
Pelvic plexus
A
L5
S2
S3
S4
Sacrum
Rectum
Bladder
Superior hypogastric
plexus at L5
Vessels and nerves
in presacral space
Line of dissection
Nervi erigentes
on lateral wall
Denonvilliers' fascia
Pelvic plexus
anterior to rectum
Denonvilliers'
fascia
B
Figure 13-2A-B
Fascia propria
of rectum
Waldeyer’s fascia
(presacral)
Anterior and posterior
planes of dissection
230 Chapter 13 • Laparoscopic Abdominal Perineal Resection
The rectum descends through the middle of the pelvis following the curve of the sacrum and
at the level of the coccyx makes a right angle to exit through the pelvic floor via the anal canal.
The levator ani muscles on either side of the pelvic floor form the support diaphragm of the
pelvis and extend up onto the side wall of the pelvis to insert in the ischiospinous ligament
attachments covering the nerves and vessels of the deep pelvic floor. The tip of the coccyx
attaches to the pubococcygeal ligament, which supports the puborectalis muscle as a semicircular sling from the pubis around the back of the rectum. This muscle closes the top of the
anal canal anterior to posterior (Figure 13-3).
The anterior pelvic structures including the bladder, prostate, and vagina are separated from
the rectum by the rectoprostatic or rectovaginal septum. A visceral peritoneal layer known as
Denonvilliers’ fascia is the posterior boundary of the anterior structures. This fascia protects the
seminal vesicles and prostate during dissection. The areolar tissue plane continues around the
entire rectum to the anterior surface of the rectum. The plane is found behind or posterior to
Denonvilliers’ fascia. The anterolateral ligaments carry the middle hemorrhoidal vessels into the
mesorectal envelope through the visceral fascia from an anterolateral direction. Dissection and
transection of these middle hemorrhoidal vessels reveals the anterior areolar tissue plane behind
Denonvilliers’ fascia, which can be followed all the way down to the anal canal.
The ureters, which have been described as running into the pelvic area over the pelvic brim
crossing the common iliac artery and vein on either side of the pelvis, continue into the pelvis
along the side wall of the pelvis toward the posterior aspect of the bladder. In the nonoperated,
pristine pelvis, the ureters are higher up along the side wall of the pelvis aiming toward the
posterior aspect of the trigone of the bladder. In females, the ureters run between the arterial
blood supply of the uterus along the anterior lateral side wall of the pelvis. In males, ureters
are not exposed during the distal pelvic dissection. The ureters may be drawn posteriorly after
a previous operation but are normally well protected anteriorly and laterally. In a previously
operated pelvis, it is always wise to place ureteral stents at the beginning of the procedure to
aid in identification of the aberrantly placed ureters.
Anal Canal Anatomy
The upper anal canal begins at the puborectalis ring or the anorectal ring, which sits at the level
of the pelvic floor and can be palpated through the anal canal as a bulge posteriorly (Figure
13-3, insert). The longitudinal muscles of the rectum continue into the anus as the intersphinc-
teric plane demarcating the line between autonomic internal sphincter and somatic external
sphincter fibers all the way down to the level of the anal canal skin where the intersphincteric
groove is palpable. The ischiorectal fossa fat is found outside the circular fibers of the external
sphincter that encircle the rectum. The pudendal nerve and vessels traverse the ischiorectal fat
from each ischial spine to the posterolateral aspect of the anal canal. During the perineal portion
of a procedure, the pudendal nerves and vessels must be controlled.
The rectovaginal and rectoprostatic septum descends all the way to the level of the perineum
anteriorly. The transverse perineal muscle separates the anterior and posterior perineum. The
terminal fibers of the longitudinal muscle of the rectum insert into the skin of the anal canal
just outside the anal verge as the corrugator cutanei ani and cause the ridges that are noticed
around the anal canal. The internal sphincter is the hypertrophied circular muscle of the wall
of the rectum. The lowest portion of the internal sphincter can be palpated as a groove where
the longitudinal fibers insert on the skin.
Within the anal canal, the dentate line is the junction between cuboidal epithelium of the
anal transition zone, which is the terminal mucosal layer of the rectum, and the squamous
epidermal cells of the anal canal skin. Gland openings (or crypts) are found in the dentate line
at the base of the Morgagni columns, which are interdigitating lines of squamous epithelium
into the cuboidal and columnar epithelium of the distal rectum. The anal transition zone is the
Chapter 13 • Laparoscopic Abdominal Perineal Resection 231
Anococcygeal
ligament
Ischiorectal
fossa
External anal
sphincter muscle
Ischial tuberosity
Figure 13-3
Coccyx
Lines of dissection
Anus
Levator ani muscle
Perineal body
Vagina
AB
Levator ani muscle
External anal
sphincter muscle
Ischiorectal fossa
CD
232 Chapter 13 • Laparoscopic Abdominal Perineal Resection
most highly innervated section of the rectum and anal canal containing nerve fibers sensing
temperature, vibration, electrical stimulation, pressure, liquid, solid, and gas. The dentate line
lies approximately halfway along the surgical anal canal, which extends from the palpable anal
verge all the way up to the anorectal ring palpated at the puborectalis sling posteriorly. The
anoderm within the anal canal, cephalad to the anal verge, has no hair follicles.
Step 2: Preoperative Considerations
Abdominal perineal resection of the rectum is most commonly performed for rectal cancers or
anal cancers involving the low rectum or anal canal or both. Removal of the entire anal canal
is required when the tumor has invaded the sphincter complex. The tumors require a total
mesorectal excision, which should also include a portion of the pelvic floor musculature. More
recent data suggest that complete removal of the pelvic floor muscle all the way out to the
ischial spines reduces the risk of local recurrence. However, the use of neoadjuvant therapy for
these tumors may reduce the need to remove all of the pelvic floor and allow the removal of
only a cuff. The tumor should not be exposed during mobilization of the mesorectum if the
tumor is posterior and lying at the level of the pelvic floor. In cases where the tumor is large
and fills the pelvis, removal of the coccyx with the pelvic floor may be necessary. The laparoscopic approach is appropriate for this portion of the procedure but may become more difficult
as the tumor gets larger and invades adjacent structures. The perineal dissection may be used
to achieve radial margins up in the low pelvis.
The patient should undergo marking for a permanent stoma with the help of an enterostomal
therapist. The patient should be educated on care of the colostomy. A complete bowel preparation is unnecessary, but it is important to empty the rectum so that spillage is minimized. The
perineal wound will require closure in some way, and arranging for plastic surgery consultation
preoperatively is usually appropriate if a large portion of the perineal skin and muscle is to be
removed. Plastic surgeons are able to swing flaps of skin, fat, and muscle to help fill the defect.
The use of biomesh for pelvic floor reconstruction is now possible and may eliminate the need
for larger flap procedures.
Step 3: Operative Steps
u
The patient is placed in the lithotomy position using Allen’s stirrups with the legs flexed 90
degrees at the knees and flexed no more than 10 degrees at the hips. The legs point toward
the floor to prevent obstruction of the operative field by the knees when the patient is placed
in the Trendelenburg position. A beanbag is attached to the table with Velcro to fix it in place.
The patient is positioned in the beanbag with the arms tucked at the side and incorporated
in the beanbag. As an extra measure of security, tape is placed across the chest to fix the sides
of the beanbag and hold the patient (Figure 13-4).
Chapter 13 • Laparoscopic Abdominal Perineal Resection 233
Figure 13-4
234 Chapter 13 • Laparoscopic Abdominal Perineal Resection
u
The abdomen is prepared and draped sterilely, and the abdomen is inflated through either
an open insertion of a trocar at the umbilicus or a Veress needle at the umbilicus. The trocar
is placed above the umbilicus in the vertical midline. The flexible laparoscope is introduced
through the trocar at the umbilicus by the camera operator standing at the right shoulder,
and the abdomen is explored for metastases or other intra-abdominal disease. Laparoscopic
proctectomy requires trocars in the right upper and lower quadrants in the anterior axillary
line; the trocars are placed two fingerbreadths below the costal margin and above the anterior
superior iliac spine. A left flank trocar is placed in the anterior axillary line at the level of the
umbilicus. A 10-mm trocar is placed in the suprapubic vertical midline, or a hand access
port can be placed at this level (Figure 13-5). The goal should be to perform a completely
laparoscopic procedure with no other incision on the abdomen besides the colostomy.
u
The patient is placed in steep Trendelenburg and airplaned to the right. The sigmoid colon
is lifted anteriorly with a Babcock clamp through the 10-mm suprapubic port or alternatively
with the hand of the assistant through the suprapubic hand access port. The assistant stands
between the legs. The operating surgeon stands to the patient’s right and holds a 5-mm
grasper in the left hand and an energy source in the right. The sigmoid mesentery is incised
at the level of the pelvic brim anterior to the sacral promontory to enter the avascular plane
at that level (Figure 13-6). Retraction anteriorly opens this plane and exposes the undersurface of the IMA at its origin.
u
The left ureter is the first structure to be identified and dissected free from the posterior
aspect of the left colon mesentery. The ureter must be visualized before division of the IMA
for safety reasons. A full laparoscopic approach is more difficult and requires anterior and
posterior countertraction and blunt dissection to drop the ureter posteriorly. The surgeon
must remember that the dissection plane is angled upward along the pelvic brim as the patient
is in right-side-down position, and the left leg is actually up in the air (Figure 13-7).
u
The IMA and inferior mesenteric vein (IMV) are isolated at their origins along the anterior
surface of the aorta and at the third portion of the duodenum at the ligament of Treitz (Figure
13-8). The medial to lateral approach incises the base of the mesentery of the left colon all
the way up to the duodenum from the IMA. A window of clear areolar tissue is exposed
posterior to the IMV as it runs parallel to the aorta along the base of the left colic mesentery.
This window can be developed, and the ureter can be seen in its course toward the hilum
of the kidney (Figure 13-9).
u
The IMA is divided at its origin using the energy source (Figure 13-10). For cancer, high
ligation of the IMA should be 1 cm above the junction of the aorta. The sympathetic nerves
can be dropped posteriorly with blunt dissection to reduce the risk of nerve injury and
impotence. The stump of the artery must be visualized carefully after division to ensure there
is good hemostasis.
Figure 13-5
Superior hemorrhoidal
IMA
Sacrum
Figure 13-6