Abdominoperineal Resection

Abdominoperineal Resection
Clifford L. Simmang, MD, MS, FACS, FASCRS
ver the past few decades there have been significant
advances in adjuvant therapy for malignant conditions of the anus and low rectum, as well as medical
therapy for inflammatory bowel disease involving the rectum and anal canal. Many of these advances have allowed
sphincter-sparing operations and in some cases, the possibility to delay or avoid surgery. In 2003, it is predicted
that there will be 42,000 new cases of rectal cancer and
4000 cases of anal cancer.1 Although the possibility of
sphincter sparing surgery following neoadjuvant therapy
either with a low double stapled anastomosis or an intersphincteric dissection and hand sewn coloanal anastomosis may be possible in many patients with cancer of the
low rectum, when the sphincter complex is involved,
sphincter sparing operations are not possible. In addition,
despite significant advances in medical therapy for inflammatory bowel disease, abdominoperineal excision is
required for most patients undergoing surgery for Crohn’s
proctitis and is occasionally selected as the operative procedure of choice by a few patients with ulcerative colitis.
Indications for abdominoperineal resection include
those patients with a malignancy involving the sphincter
complex,2 patients with Crohn’s proctitis and anal disease,3 patients with ulcerative colitis preferring to have a
stoma or those patients with any of the above conditions
who already suffer with incontinence and would be debilitated by a low anterior, coloanal, or ileal pouch anal
anastomosis. These patients have a superior quality of life
with their stool evacuation from either an ileostomy or a
colostomy into a contained bag allowing them the freedom to live a normal life.
Preoperative preparation and education of the patient
is important before creating a stoma. An Enterostomal
Therapist (ET) should visit with the patient and discuss
what a stoma is and what appliances are available and
how they would function. The ET nurse will then perform
preoperative stoma siting. The stoma should be sited
away from creases and in a location that the patient can
see. It is preferable to mark more than one location in the
O
From the University of Texas Southwestern Medical Center at Dallas, Dallas,
TX.
Address reprint requests to Clifford L. Simmang, MD, MS, FACS, FASCRS,
5323 Harry Hines Blvd., Dallas, TX 75390-9156.
© 2004 Elsevier Inc. All rights reserved.
1524-153X/04/0504-0006$30.00/0
doi:10.1053/joptechgensurg.2003.10.005
240
possibility that the bowel may not easily reach the preferred location and an alternative site should be marked.
In preparation for an abdominoperineal resection, patients undergo a standard bowel preparation with mechanical evacuation of the large bowel often using a
balanced electrolyte solution (GoLytely威, Braintree Laboratories, Braintree, MA) along with an antibiotic prophylaxis. We use a combination of neomycin 1 g and metronidazole 1 g at 1 PM, 2 PM, and 9 PM the evening before
surgery. Bowel preparation is performed at home and the
patients arrive to the hospital before their planned operative procedure. Before the start of the operation, additional antibiotic prophylaxis is given intravenously. Although many antibiotic regimens are appropriate, we use
Cefotetan威 (Astra-Zeneca, Wilmington, DE) 2 g before surgery and 1 g at 12 and 24 hours later. After the perioperative
dosing of antibiotics, further antibiotics are not used.
In the operative room the patient is positioned in a
modified lithotomy position (Fig 1). The rectum is prepared by insertion of a 32 French Malecot catheter followed by lavage with normal saline solution. Once clear,
full strength Betadine solution is instilled within the rectum for its tumorocidal properties. The Malecot catheter
may be left as a drainage tube for evacuation of residual
colonic contents during the operation and to prevent accumulation of residual stool in the rectum during the
pelvic or perineal dissection. Alternatively, some surgeons prefer to encircle the anal canal with a suture such as
a #1 Prolene to occlude the anal orifice. If the procedure is
performed for anal cancer, this often is not possible.
Most commonly, a midline incision is created and
curves around the umbilicus opposite the side of the
planned stoma. If a colostomy is planned the incision will
curve to the right of the umbilicus and if an ileostomy
were planned it would then curve to the left. The fascia is
divided along the linea alba and the peritoneal cavity is
entered. On entering the peritoneal cavity exploration
should be performed. In patients with malignant disease,
careful palpation of the liver is important and intraoperative ultrasonography can be performed. The upper abdominal contents should be gently palpated and then the
intestines inspected. After palpating the stomach and duodenum, the small bowel should be palpated and inspected from the ligament of Treitz to the ileocecal valve.
This is to identify concomitant pathology that may need
attention at the time of this operation. The colon is then
palpated throughout, as are the retroperitoneal structures.
Operative Techniques in General Surgery, Vol 5, No 4 (December), 2003: pp 240-256
Abdominoperineal Resection
Mobilization is begun by incising the lateral peritoneal
attachments just above the white line of Toldt. This allows entry into an areolar fusion plane (Fig 2). As the
colon is further mobilized, a second fusion plane is identified and dissection continues in this plane allowing the
retroperitoneal structures to remain posterior. The gonadal vessels are seen and identified first (Fig 2). The next
tubular structure is the ureter and it is important in all
dissections of the left colon to clearly identify the ureter
and avoid injury. Following mobilization of the sigmoid
colon this can be carried superiorly and the splenic flexure mobilized. Once lateral mobilization is complete, a
window is created underneath the superior hemorrhoidal
vessels at the level of the sacrum (Fig 2). The peritoneum
can be opened distally to allow enlargement of this window. The peritoneum is then incised proximally at this
level just below the superior hemorrhoidal vessel. Continuing in this plane superiorly will lead to the origin of
the inferior mesenteric artery (IMA). Once encountered,
the IMA is ligated near its origin from the aorta.
Adjacent is the inferior mesenteric vein, which is then
divided between clamps. Although I prefer to divide the
IMA near its origin (Fig 3), some surgeons will divide the
IMA after the take off of the left ascending colic artery.
Although no oncologic benefit has been demonstrated
from a high ligation of the IMA, a high ligation does
provide a significant increase in the mobility of the colon.
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Once the major arterial trunk is divided this defines the
proximal margin of resection. The mesentery is divided to
the colon, which will be near the junction of the descending
and sigmoid colon. The colon is then divided with a linear
cutting stapling device, which allows separation and prevents spillage or contamination of colonic contents (Fig 3).
Once the colon is divided, attention is directed toward
the pelvic dissection. This is begun in the posterior plane.
Continuing to mobilize the rectum in the avascular embryonic fusion plane will allow a total mesorectal excision
to be performed using a nerve sparing technique as the
hypogastric nerves can be readily identified during this
dissection (Fig 4). There will be branches given off as the
nerves traverse the pelvis, but the main trunk should be
identified and preserved during the main dissection (Fig
4). A deep pelvic St. Mark’s type retractor is very useful
for getting lift on the rectum and allowing this areolar
tissue plane to become readily visible. Dissection of the
rectum should be performed sharply under vision. I prefer to use electrocautery as it does aid in hemostasis especially in the area of the lateral stalks (Fig 5). As progress
dissecting the posterior rectum continues and tethering is
noted from the lateral peritoneal reflection, this should be
incised and divided. This will allow for further mobility
with the rectum. Sharp dissection will allow sharp division of Waldeyer’s fascia. Blunt pelvic dissection by sliding the operator’s hand behind the rectum has led to a
Lithotomy positioning. The operative position for a synchronous abdominoperineal resection is low lithotomy. This is most
often accomplished with the use of adjustable stirrups to allow for a gentle flex at the knees and elevation of the lower extremities.
Elevation of the lower extremities assists in promoting venous drainage, which may reduce the incidence of venous thrombosis.
Sequential compression devices are also used for prophylaxis not only for venous thromboembolism, but also as an additional
cushion to prevent nerve injury. The patient’s position must be inspected for appropriate padding. A soft roll, which may be a sheet
or a blanket, may be placed underneath the patient’s buttocks to aid in elevation and exposure for the perineal portion of the
operation. Once in position, the anal canal may be closed with a heavy suture to prevent perineal contamination.
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higher incidence of rectal perforation because of the adherence of Waldeyer’s fascia. Sharp dissection and division will decrease this complication. Circumferential dissection is now performed by incising the peritoneum at
the base of the cul-de-sac. For a low rectal cancer, especially if this is in an anterior location, the anterior dissection should be performed on the prostate side of Denonvilliers’ fascia (Fig 6). If the tumor is posterior, and then
the anterior dissection in men may be on the rectal side of
Denonvilliers’ fascia, which will decrease the likelihood
of nerve injury. This circumferential dissection is continued until a complete mesorectal dissection is performed
and the rectum has coned down to the narrow muscular
tube as it enters into the anal canal. In women, the anterior dissection begins at the depth of the cul-de-sac (Fig
7) and proceeds through the avascular plane in the rectovaginal septum. If adherence is noted during this dissection, especially anteriorly, it may be prudent to wait for
the perineal operator to begin and approach the most
tethered area simultaneously abdominally and perineally.
If the tumor is tethered to the posterior vaginal wall, a
posterior vaginectomy should be performed (Fig 8). The
perineal approach begins with a standard posterior incision, however the anterior incision proceeds to incorporate an ellipse of the posterior vagina (Fig 9). Once the
specimen is delivered, the posterior vagina and the perineal body can be reconstructed with absorbable sutures
(Fig 10). The proximal end of the colon can be passed
posteriorly to better visualize the last anterior attachments (Fig 10). In men, if the tumor appears tethered to
Denonvilliers’ fascia, a superficial layer of the prostate
capsule can be encorporated. However, if there is invasion
within the prostate, a combined en bloc proctectomy with
cystoprostatectomy (anterior exenteration) is required.
This possibility should have been detected, discussed,
and planned for preoperatively and a surprise in this location should not occur.
The perineal dissection is most often performed synchronously with the completion of the pelvic dissection.
An elliptical incision is made centering on the perineal
body anteriorly and the mid point between the anal canal
and the coccyx posteriorly (Fig 11A). The skin is incised
and the incision is carried into the ischiorectal fat. This
dissection is performed circumferentially by continually
going from one location and one side to another to
achieve length and advance the dissection. The dissection
should be in the ischiorectal fat outside of the sphincter
complex. The neurovascular bundle to the anus enters in
the posterolateral location and caution should be exercised with dissection in this area and anticipate the possible need for hemostatic control. I prefer to enter the
peritoneal cavity in the posterior location. A malleable
retractor can be inserted deep into the pelvis and easily
palpated by the perineal surgeon. Using cautery, the incision can be carried directly onto this retractor. Once entry
into the peritoneal cavity is gained, the dissection contin-
Clifford L. Simmang
ues circumferentially on either side. At times a finger can
be placed through this opening and the surgeon can cauterize through the levators onto his finger on the peritoneal pelvic side (Fig 11B). This division is continued on
both sides leaving the anterior dissection yet to complete.
If the plane of dissection is clearly defined, the anterior
dissection is completed (Fig 11C). However, if there is
adherence or the operative planes are difficult, exposure
can be improved by passing the proximal end of the sigmoid colon out the posterior opening of the levators (Fig
10). This allows traction from both the proximal and distal
aspects of the rectum and can aid in helping define the plane
required for transection to achieve a grossly clear margin.
There are special considerations when performing APR
for anal cancer or IBD. For patients with IBD where this
operation is being performed for an inflammatory condition of the rectum, an intersphincteric proctectomy is
preferred.4 This achieves resection of all diseased bowel
while limiting the size of the perineal wound and increasing the likelihood for primary healing. However, for those
patients with anal cancer, especially if there is a significant
component onto the anal margin, a wide perineal skin excision will be required. This wound cannot be closed primarily
and must then be repaired with a flap. A very difficult wound
may be treated with wound care or even a wound vac to
promote healing or allow the addition of a flap.
The perineal wound is closed in layers. I use a series of
2-0 figure of eight absorbable sutures and attempt to approximate the levators, if possible. If this has been a very
wide excision, there will be little left and all that can be
approximated is the subcutaneous ischiorectal fat. There are
sufficient fibrous septae running through this fat to allow for
closure. The skin is closed with subcuticular sutures. One or
two pelvic drains are placed abdominally and are brought
out through separate abdominal stab incisions. I believe that
transabdominal drainage is preferable to perineal drainage,
as this is as effective and much more comfortable for the
patient. Some surgeons omit drainage all together.
The colostomy is fashioned by excising a quartersized disc of skin and core of subcutaneous fat (Fig 12).
The anterior rectus sheath is identified and incised
longitudinally. The skin and fascia are kept in alignment by the use of Kocher clamps to assure that after
the colostomy is brought straight through and when
the skin is later closed, that the angle does not change.
The abdominal wall is then elevated as a curved Mayo
scissors is passed between the fibers of the rectus muscle and the tips are opened to allow a longitudinal
incision of the posterior rectus sheath to be made. The
passage through the rectus is then maintained and dilated to allow two fingers to easily pass through. The
end of the colon is then brought up through this opening and will be allowed to remain there until the abdomen is closed (Fig 13). It is matured as the last step to
avoid contamination of the incision. It is not necessary
to tack the colostomy to the posterior fascia. The mid-
Abdominoperineal Resection
line incision is closed and the staple line excised from
the distal end of the colon. The colostomy is matured
by performing interrupted sutures in the colon beginning at the mucoserosal junction with about 1 cm of
distal colon within this suture and then placing the
suture through the skin about 5 mm from the edge.
Although subcuticular sutures are preferable when ma-
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turing ileostomies, colostomies can be matured with a
full thickness of skin. Some surgeons will also encorporate a three-point suture fixation everting the colostomy much like a Brooke ileostomy is performed. Although this is not necessary for a colostomy, it will help
prevent retraction. A stoma appliance it then placed around
the stoma and a dressing placed over the incision.
Left colon mobilization. After entry into the abdominal cavity and thorough exploration, the operation is begun by mobilization of the left colon. Although some surgeons will begin with a high ligation of the IMA, performing the “no touch” technique by
ligating the vascular pedicle before colonic manipulation, most surgeons begin with lateral mobilization. The peritoneal reflection
is incised with electrocautery. This incision lies just inside the white line of Toldt. As the colon is elevated a second retroperioneal
fusion plane is identified and dissection progresses in the avascular areolar tissue plane. As this progresses medially, the first set of
tubular structures to be encountered will be the gonadal vessels. Key to avoiding injury to the ureter is to recognize that inferior to
the IMA, the ureter lies medial to the gonadal vessels. The ureter is identified next and the colon is mobilized proximally. This
proximal mobilization is carried superiorly and around the splenic flexure to provide adequate mobility of the left colon, as needed.
Following mobilization of the left colon a plane is developed underneath the superior hemorrhoidal artery.
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3
Clifford L. Simmang
High ligation of the inferior mesenteric artery. A window is created on the right, medial side of the sigmoid colon mesentery
underneath the superior hemorrhoidal artery. The peritoneum is then incised just inferior to the superior hemorrhoidal artery and
this window is enlarged until the inferior mesenteric artery is encountered. The inferior mesenteric artery is then divided between
clamps and ligated. This division defines the mesenteric dissection leading to the site on the colon, which will represent the
proximal margin that was defined by division of its vascular mesentery. The colon is divided with a linear cutting stapling device.
Abdominoperineal Resection
4
Autonomic nervous plexus and innervation of the pelvic structures. The most common
sites for potential nerve injury can be seen.
Sympathetic injury may occur at the aortic
plexus near the origin of the IMA or over the
sacral promontory at the division of the hypogastric nerves from the hypogastric plexus. In
addition to sympathetic injury, parasympathetic injury may occur during lateral dissection, especially when there is division of the
lateral ligaments or anterolaterally during dissection behind the seminal vesicles and prostate.
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Clifford L. Simmang
Division of lateral ligaments. A fibrous condensation containing the middle hemorrhoidal vascular pedicle makes up the lateral
ligaments. Traction on the rectum to the opposite side will allow this structure to be identified as a curtain of tissue. Often, this
vascular pedicle is not prominent and can be divided by cautery, especially if the patient has undergone neoadjuvant therapy. If a
prominent vascular pedicle is present, it may be divided between ties, clips, with an ultrasonic device (Autosonics威 US Surgical
Corporation, Harmonic Scalpel威 Ethicon Endosurgery) or using a vascular endoscopic stapler (US Surgical Corporation, Ethicon
Endosurgery).
Abdominoperineal Resection
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Anterior dissection in men. Following the posterior dissection the lateral peritoneum is incised. An incision is made 5 mm
anterior to the fold of the cul-de-sac. The seminal vesicles are exposed and using sharp dissection most commonly with cautery, the
seminal vesicles are cleared. The plane of dissection continues anterior to encompass Denonvilliers’ fascia until the junction with
the prostatic capsule. Further distal dissection is between the mesorectal fat and the prostatic capsule, staying as wide as possible.
For a tumor in the anterior location Denonvilliers’ fascia should be separated from the prostatic capsule as needed to provide a clear
and free radial margin from the tumor.
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Clifford L. Simmang
7
Anterior dissection in women.
When present, uterine traction superiorly helps lift the anterior aspect of the cul-de-sac. The peritoneum is incised with cautery at the
peritoneal reflection. Dissection
proceeds along the rectovaginal
septum in an areolar tissue plane.
The posterior vaginal surface can
be identified by its white encompassing visceral fascial layer. Dissection proceeds throughout the
rectovaginal space exposing the anterior junction of the levators at the
level of the perineal body. At this
point the lateral sidewalls dissection can be completed.
Abdominoperineal Resection
8
Anterior rectal cancer involving the rectovaginal septum requiring posterior vaginectomy.
This dissection may be performed either by a synchronous team in the lithotomy position or a single operative team approach where the abdominal
portion has been completed and the operation is
now performed in prone position as demonstrated
here. Lines for transection are shown encorporating the colon, sphincter complex and posterior
vagina next to where the rectal lesion is located.
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