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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_832_Библиотеки_им_академика_М_И_Перельмана
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radiation, diverticulitis, stulas, Crohn’s disease, and obesity [12]. The abdomen is
sterilely prepped with an alcohol-based solution (e.g., chlorhexidine) in preparation
for procedure initiation [13].
M. Unuvar and R. L. Hoffman
3 Intraoperative Care
Anesthesia that promotes recovery of gastrointestinal motility is critical to enhanced
recovery. Primary goals during anesthesia are limitation of the stress response to
surgery, uid balance, and analgesia. Lung-protective ventilation strategies are used
for all patients. Short-acting anesthetic agents are preferred during all phases of
anesthesia to allow recovery to begin as quickly as possible after the case concludes.
Standard physiologic monitoring during the procedure is achieved with a blood
pressure cuff, pulse oximeter, and bladder catheter. A temperature probe is also
placed to ensure normothermia, as alterations in body temperature can lead to coagulopathy, adverse cardiac events, and decreased resistance to surgical wound infections [14]. Patients also undergo hourly glucose monitoring to prevent
hyperglycemia.
Regional anesthetic blocks are commonly used to minimize anesthetic requirements and reduce postoperative narcotic use. An epidural catheter with bupivacaine
infusion can be used for patients undergoing open surgeries, but this should be
avoided in laparoscopic colorectal resections as it has been shown to impede recovery in these cases [15]. Instead, most patients undergoing laparoscopic surgery
receive a transverse abdominis plane (TAP) block, which has been shown to facilitate shorter length of stay in an efcient and cost-effective manner [16].
All patients receive intraoperative antiemetics before the end of the case for prevention of postoperative nausea and vomiting, as this is a common barrier to early
recovery. Common agents include dexamethasone, ondansetron, or haloperidol.
Liberal use of uids perioperatively is associated with delayed return of normal
GI function and may increase postoperative complications associated with volume
overload. Therefore, reduced volume maintenance IV uids are given continuously
throughout the case with selective uid boluses as warranted [17, 18]. A urine output of 0.2mL/kg/h is considered acceptable.
Colorectal surgeries by nature have relatively frequent contamination of the sterile eld and surgical equipment that becomes soiled must be handled with care.
Wound protectors are used routinely as these have been shown to reduce surgical
site infections signicantly (Fig.2) [19]. The surrounding operative eld may also
be protected with surgical towels at the time of bowel division. Ideally, after the
bowel is closed, all contaminated instruments including suction tips and electrocautery are passed off the eld. All surgeons and assistants should then change their
gloves before proceeding.
Routine use if intra-abdominal drains and nasogastric (NG) tubes should be
avoided. NG tubes do not improve symptoms of nausea or vomiting, time of return
to bowel function, or length of stay in the immediate postoperative period [20–22].
abc
de
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Fig. 2 Placing a wound protector aids with both infection control and retraction. Panel a demonstrates the appliance. Different sizes are available depending on the size of the wound, and some
wound protectors allow a cap to be placed on top (GelPortTM) for hand-assist/laparoscopic access.
The green ring is placed under the fascia (panels b and c) and then the white ring is rolled until the
wound protector is tight to the skin (panels d and e)
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Intra-abdominal drains placed during the index operation do not improve postoperative outcomes and are associated with drain-related complications and should therefore be avoided [23, 24]. Foley catheters should be removed at the end of the case
whenever possible.
4 Operative Approach
Regardless of which surgical procedure is chosen, there are two general approaches
to mobilization of the sigmoid colon. The lateral-to-medial approach rst separates
the colon from its lateral attachments along the White Line of Toldt. Alternatively,
the medial-to-lateral approach enters the retroperitoneal fusion plane under the vascular pedicle as the initial step. Both techniques ultimately accomplish the same
dissection, and it is important for surgeons to have mastered them both. Some studies have shown that the medial approach may result in less blood loss, earlier return
of bowel function, shorter hospital stays, and increased number of lymph nodes
harvested compared to the lateral approach [25, 26].
4.1 Key Steps
1. Patient is placed in low lithotomy position with both arms tucked and buttocks
positioned at the edge of the table.
2. Access the abdominal cavity, position the patient accordingly (Trendelenburg,
“airplaned” left side up).
3. Explore the abdomen for metastatic disease (if operative indication is
malignancy).
4. Mobilization of the colon (can either be “lateral-to-medial” or
“medial-to-lateral”).
For lateral-to-medial approach:
(a) Incise the White Line of Toldt to release the colon’s peritoneal attachments.
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(b) Identify and preserve the ureter.
(c) Mobilize the splenic exure (optional, depending on length of colon needed
for anastomosis).
(d) Inferior mesenteric artery (IMA) ligation.
For a medial-to-lateral approach:
(a) Incise the retroperitoneal fusion plane under the inferior mesenteric
artery (IMA).
(b) Identify the retroperitoneal fusion plane and lift the colon mesentery toward
the abdominal wall, leaving the retroperitoneum down.
(c) Identify and preserve the ureter.
(d) Inferior mesenteric artery (IMA) ligation.
(e) Divide the lateral attachments along the White Line of Toldt.
(f) Mobilize the splenic exure (optional, depending on length of colon needed
for anastomosis).
5. Colon transection.
6. Mesorectal dissection of the upper rectum.
7. Transect at the rectosigmoid junction/upper rectum.
8. Remove specimen.
9. Create anastomosis.
10. Leak test.
11. Abdominal closure.
M. Unuvar and R. L. Hoffman
5 Open Sigmoid Colectomy
After the patient is positioned, an exploratory laparotomy is performed by creating
a lower midline incision from umbilicus to pubis. Care should be taken to avoid the
bladder inferiorly by incising the peritoneum in a lateral direction as the incision
nears the pubic symphysis. Wound protectors are placed, as these have been shown
to decrease rates of surgical site infections (Fig.2) [19]. The patient is then placed
in slight Trendelenburg with the table “airplaned” with patient’s left side up to facilitate packing the small bowel into the right upper quadrant of the abdomen for
improved exposure. The sigmoid colon is retracted towards midline to expose the
White Line of Toldt. Electrocautery is used to make an initial entry into the retroperitoneal fusion plane and then a combination of blunt dissection and electrocautery are used to release the lateral attachments along the line of Toldt (Fig.3). This
is extended proximally and distally in a bloodless plane. The sigmoid and descending colon mesentery are separated from the retroperitoneum with continuous gentle
rolling of the colon in a lateral-to-medial direction towards midline. It is during this
step that the left ureter should be identied. In the lower abdomen, it is often seen
medial to the gonadal vessels, crossing over the common iliac artery at the pelvic
brim. Stimulation of the ureter with a gentle pinch causes it to vermiculate, which
helps to conrm the anatomy.
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Fig. 3 In an open colectomy, dissection typically begins laterally, at the White Line of Told,
shown here (in an exaggerated fashion due to the dilation of this colon). Once a rent is scored at
the line, a nger can typically be nuzzled in this plane to create space (panel a) and electrocautery
used to divide the tissue (panel b)
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abc
Distal transverse
Descending colon
colon
Omentum
Splenic flexure
Fig. 4 The lateral dissection proceeds proximally towards the splenic exure, rolling the colon
medially away from the retroperitoneum (panel a). When necessary, the splenic exure attachments may need mobilized in order to achieve adequate length on the colon for anastomosis. The
splenic exure attachments are typically thicker than those along the White Line. When the omentum is encountered at the distal transverse colon, the distal omental-colic attachments should be
divided in the avascular plane close to the colon. This will allow access to the lesser sac (panels
b and c)
Mobilization of the splenic exure is not always required, but aids in creating a
tension-free anastomosis in many cases. Care must be taken as bleeding from the
spleen can occur that may be difcult to control. The splenocolic ligament, which is
typically thicker than expected, is divided with cautery as the turn around the exure is made (Fig. 4). Continued blunt, gentle rolling of the colon medially will
facilitate this maneuver. The gastrocolic ligament and distal omental-colic attachments are divided until the lesser sac is entered. Finally, attachments of the splenic
exure to the tail of the pancreas are taken down. The left colon should now be
mobilized to the midline.
The proximal and distal sigmoid colon is held up in order to expose the root of
the sigmoid mesocolon. The IMA is then dissected circumferentially and ligated
Omentum
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M. Unuvar and R. L. Hoffman
Colon
IMA pedicle
Mesentery
Bipolar
energy
device
Fig. 5 Panel a: A window is created on either side of the inferior mesenteric artery (IMA) pedicle
and an energy device (in this image) is used to divide it. Conrmation of the location of the ureter
should always be conrmed prior to dividing. A stapler or suture-ligature may also be used to
divide the pedicle. Panel b: An energy device is used to march proximally along the colon mesentery to the desired point of division. Care is taken to preserve the marginal artery, which runs parallel along and close to the colon
(using either a stapler, clips, ties, or bipolar cautery), taking note of the location and
safety of the ureter prior to doing so (Fig.5). The colon mesentery is then divided
between the sigmoid and descending colon to the pre-determined points of colonic
transection. The colon is transected proximally (most commonly with a linear cutting stapler or sharply) between the sigmoid and descending colon segments (usually at the level of the IMA takeoff). Distal transection is then performed (typically
with a TA or Contour™ stapler) just past the rectosigmoid junction (Fig. 6). The
remaining mesenteric attachments are then divided, and the specimen is removed.
A stapled or hand-sewn anastomosis can be performed with equivalent rates of
anastomotic leaks [27]. For stapled anastomoses, creation of an end-to-end anastomosis (EEA) is most common. An end-to-side or side-to-side anastomosis may also
be created, however, depending on the anatomical considerations. The EEA stapler
size is chosen based on the colon size (typically a 29mm is used) (Fig.7). The stapler anvil is placed in the descending colon limb by making a colotomy and placing
a purse-string suture circumferentially. It is important to ensure good apposition of
the bowel to the anvil shaft circumferentially, which often means excluding epiploica, colonic fat and diverticula from the surface of the anvil. After the anus and
rectum are dilated, the end-to-end circular (EEA) stapler is then inserted transanally into the rectum and the stapler spike is extended (opened) at the preferred
location on the rectum so that it may be approximated with the anvil. The tension on
the anastomosis is checked and the proper orientation of the mesentery (to make
sure no twisting has occurred) is conrmed prior to ring the stapler. After the
Bipolar
energy
device
c
e
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a
Sigmoid
b
Rectum
Fig. 6 Division of the rectosigmoid junction. Panel a depicts a ContourTM stapling device, which
is curved to allow better t into the pelvis. This is only one of a few options for dividing the colon
at this point. Panel b depicts a linear cutting stapler, which could also be used. This device afxes
a row of staples on each side of the desired transection point and cuts between them. The color of
the stapler load refers to the size of staples, and the “75” refers to the length of the staple line (in
this case, 75mm). Panels c and d demonstrate the ContourTM stapler being placed across the
rectosigmoid junction. Panel e shows the rectal staple line
Spike
d
Anvil
Sigmoid
Rectum
Staple Line
Rectum
Descending colon
Circular
Sizers
Fig. 7 The anastomosis can be hand-sewn or stapled. The end-to-end (EEA) stapler is shown in
Panel a, along with the rectal sizers. The sizers are introduced rst to conrm location, stretch and
appropriate landing zone for the stapler. The anvil is secured into the proximal colon. Then, the
EEA stapled is introduced transanally and advanced to the rectal staple line. The spike is advanced
and then the anvil with proximal colon attached is married to the spike. The ends are brought
together as the stapler is closed and then “red,” or stapled. Panel b shows an endoscopic view
looking up the colon from the rectum of the stapled anastomosis
staple
line
Rectum
stapler is red, it is then opened and slowly removed from the rectum and anus
using small twisting motions. The anastomotic rings are then inspected for completeness and sent as a specimen for pathologic evaluation. Alternatively, a handsewn anastomosis may be performed using a double layer closure. An absorbable
suture is placed full thickness through the colon and rectum walls in a running
fashion. The second layer is performed by placing absorbable suture with the
Lembert technique through the serosa of the colon and adventitia of the rectum to
form a buttress. No anastomotic rings are produced with a hand-sewn anastomosis.
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After the anastomosis has been created, many surgeons will evaluate its integrity
by performing an air-leak test. The surgeon occludes the proximal colon with his/
her ngers and submerges the anastomosis under saline irrigation. The rectum is
then insufated with air using a exible endoscope and the surgeon carefully
observes for air bubbles. A rigid proctoscope can also be used for performing a leak
test, but it does not allow for intraluminal visualization of the anastomosis as exible endoscopy does. Finally, the abdomen is inspected for hemostasis before closing
the abdominal wall using the surgeon’s preferred technique.
M. Unuvar and R. L. Hoffman
6 Minimally Invasive Sigmoid Colectomy
Minimally invasive approaches to colon resections have been shown to result in
decreased blood loss, decreased pain, accelerated food tolerance, earlier return of
bowel function, earlier return to baseline level of function, and shorter lengths of
hospital stay. Rates of wound infections are decreased with minimally invasive techniques, but rates of deep space infections remain the same [28–30]. Disease-free
and overall survival for patients with colon cancer undergoing open or minimally
invasive approaches are comparable [31]. Minimally invasive colon resections can
be performed with laparoscopic, hand-assisted laparoscopic, or robotic-assisted
laparoscopic techniques. These differ in setup and instrumentation, but the overall
operative principles remain the same. The techniques described in the following
sections are one of several acceptable approaches to these procedures. Therefore,
variation can be expected across institutions and among surgeons.
7 Laparoscopic Sigmoid Colectomy
After the patient is positioned and draped, the surgeon stands on the patient’s right
side with the scrub nurse standing to their right. The assistant stands on the left side
of the table. Two monitors, one facing the surgeon and one facing the assistant, are
used. Entry into the abdomen can be accomplished via an open Hasson technique,
Veress needle, or Optical entry at the surgeon’s discretion. The abdomen is insufated, and the laparoscope is inserted. The abdominal cavity is inspected rst before
proceeding to place three additional 5-mm working ports under direct visualization
in the right upper, right lower, and left lower quadrants of the abdomen. Adhesions
are lysed if necessary. The operating table is rotated into Trendelenburg position
with the patient’s left side up to improve exposure and retraction of the omentum
and small intestine into the right upper quadrant.
While the lateral-to-medial approach may be more commonly used during open
sigmoidectomies, the medial-to-lateral dissection is technically less challenging to
perform with a minimally invasive approach and is therefore more commonly used
during these procedures. As mentioned previously, the medial-to-lateral dissection
b
a
d
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may benet patients by decreasing blood loss, increasing lymph node harvest, and
decreasing the time to return of bowel function and length of hospital stay [25, 26].
Using a bowel grasper, the sigmoid colon is lifted toward the anterior abdominal
wall which tents the base of its mesentery at the sacral promontory (Fig.8, panel b).
Access to the proper avascular plane posterior to the inferior mesenteric vessels is
easiest at the sacral promontory. The peritoneum is incised below the IMA across
the promontory. A wide mesenteric window is created around the origin of the IMA
toward the IMV.The line of fusion of the sigmoid mesentery and retroperitoneal
fascia is identied underneath the inferior mesenteric vessels and the RP fascia is
swept dorsally. The dissection is continued from medial to lateral, beginning at the
separation of the mesocolon and the retroperitoneum, exposing the left ureter and
gonadal vessels, which are preserved in the retroperitoneum (Fig.9). Only after
these structures are identied should the IMA be divided (Fig.10). Division of the
IMA pedicle can be done in multiple ways depending on surgeon preference. Some
surgeons prefer to staple the pedicle, others clip and use bipolar cautery, and some
may use a bipolar cautery device alone. The hypogastric nerve plexus is located
next to the IMA takeoff and affects sexual function in males. The dissection should
therefore proceed directly beneath the pedicle and extend laterally. The sigmoid
and descending mesocolon are dissected off the retroperitoneum with the
Sigmoid (epiploica)
IMA Pedicle
Fig. 8 Initial steps of a robotic (and laparoscopic) medial to lateral approach. Panel a shows the
surgeon at the robotic console. After placing the omentum over the liver and moving the small
bowel into the right hemi-abdomen, the retroperitoneum at the base of the rectosigmoid junction
(just anterior to the sacral promontory) is exposed (Panel b). Note the way the light reects off of
the tissues and the subtle differences in the appearance of the vasculature to show the access (white
line, panel b) to the retroperitoneal fusion plane under the inferior mesenteric artery. In Panel c,
the peritoneum is scored along this line to gain access and begin the dissection(panel d)
Colonic mesentery
Fig. 9 Accessing the retroperitoneal fusion plane under the IMA pedicle (panel a). In the retroperitoneal space, the structures, in order of encountering them from medial to lateral, should be
ureter, gonadal artery, and then psoas tendon (panel b)
Rectum
c
Rectum
Colonic mesentery
Ureter
Retroperitoneum
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Fig. 10 The IMA pedicle
can be divided with bipolar
electrocautery (as shown
here) or a stapling device,
once the retroperitoneal
structures (ureter) have
been safely dropped down
and away
M. Unuvar and R. L. Hoffman
Retroperitoneum
Under the colon mesentery
Retroperitoneum
c
Lateral abdominal wall
Free space (the same
space that was
dissected in panel A)
b
Free space
Sigmoid Colon
d
Opening the free space
Fig. 11 Dissection continues, pushing the retroperitoneum down (panel a) until the lateral
abdominal wall is encountered and until the top of the kidney (Gerota’s fascia) is pushed down and
away from the colon. The dissection then transitions to a lateral approach(panel b). The starting
point is identied by the thin, purple tissue lateral to the sigmoid colon(panel c), which is the dissected plane from under the IMA pedicle. This "free space" which connects to the medial dissection is opened with cautery (panel d)
medial-to-lateral approach. The majority of colonic mobilization comes from this
separation off the retroperitoneum rather than release of the lateral attachments
along the White Line of Toldt. The mesocolon is held up (anteriorly) and the surgeon dissects along the transition between Gerota’s fascia in the retroperitoneum
and the mesocolon (Fig. 11, Panel a). This dissection is carried laterally to the
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abdominal wall, superiorly to the splenic exure, and inferiorly to the level of the
pelvic inlet. The ureter and gonadal vessels should again be identied and preserved
intact in the retroperitoneum. After completing the medial-to-lateral portion of the
mobilization from the sacral promontory to the splenic exure over Gerota’s fascia,
the lateral retroperitoneal attachments are divided off the sigmoid colon by retracting the colon medially and transecting them from a lateral direction (Fig.11, Panels
b, c, and d). It is important to once again identify the left ureter and gonadal vessels
to avoid injuring them. If done properly, only a small amount of lateral dissection
should be needed before the dissection plane created from the medial side is encountered. The lateral mobilization is taken superiorly toward the splenic exure. If necessary, the exure is mobilized as described above.
The point of distal transection is then selected. A spot just distal to the rectosigmoid junction (identied by splaying of the tinea coli) is chosen. The mesentery is
scored at this point close to the bowel wall. The mesorectum is divided at this location with cautery while being cautious not to injure the bowel wall. The colon is
then transected with a laparoscopic stapler.
To perform an extracorporeal (“outside the body”) anastomosis, the abdomen is
desufated, the umbilical port is extended, and a wound protector is placed. The
sigmoid colon is pulled through this incision until an appropriate location for the
proximal side of the anastomosis is reached. The bowel is transected at this location
and the sigmoid colon is passed off the surgical eld as specimen. A purse string
suture is placed either manually or by using a purse string device. The anvil for an
EEA stapler is placed in the descending colon and the purse string suture is drawn
up and tied.
The colon with the anvil in place is dropped back into the abdomen and the fascia
fashioned shut (or covered with a gel-port) so that insufation can be established
once again. Under laparoscopic visualization, the anus and rectum are dilated, and
the EEA stapler is inserted into the anal canal until it reaches the proximal rectum.
The spike is advanced through the rectal wall next to the staple line. The spike and
anvil are approximated, and the EEA stapler is closed and deployed. The stapler is
then removed, and the anastomotic donuts are inspected for completeness. A leak
test is performed prior to abdominal closure.
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8 Hand-Assisted Laparoscopic (HAL) Sigmoid Colectomy
This approach uses a hand access port to assist with dissection and resection. It
restores tactile feedback to the surgeon and facilitates dissection in cases with complicated anatomy. The HAL sigmoid colectomy maintains all of the established
short-term outcome benets of conventional laparoscopic surgery over open surgery. It is also associated with a higher usage rate, decreased operative times, and
lower conversion rate to open approach when compared with a conventional laparoscopic approach [31]. Postoperative complications are equivalent and long-term
oncologic outcomes are similar between all approaches.
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