Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_629_Библиотеки_им_академика_М_И_Перельмана
.pdf
Danger point
Depth of incision
1
Longitudinal section
of pylorus
Pyloromyotomy
2
Mucosa
Avascular area
Pylorus rotated anteriorly
3
Incision in avascular area falls
just short of duodenal edge of mass
4
Lumen
Spreading muscle
until mucosa bulges
to level of serosa
Thickened muscle
Cross section of pylorus
Intussusception
5
Lumen
Serosa
Mucosa
End result
7
6
Ileum
intussusception
Transverse colon
Normal position
Cecum
intussuscipiens
Ileum
Edematous and
hemorrhagic ileum
Normal ileum
123
PLATE
53
INDICATIONS Excision of a Meckel’s diverticulum is performed when the
diverticulum is found to cause an acute abdominal condition. Frequently
excision is a benign incidental procedure during a laparotomy for other
causes. e majority of these diverticula cause no symptoms, but a diseased
one can successfully mimic many other intestinal diseases, any of which
would require exploratory laparotomy.
e presence of gastric mucosa in the diverticulum can produce ulceration
with massive intestinal hemorrhage with brick-red stools, in ammation, or
a free perforation with peritonitis, particularly in children. Although similar
complications can occur in adults, intestinal obstruction caused by xation of
the tip of the diverticulum or a connecting band running to the umbilicus is
not uncommon. e diverticulum may become inverted and form the starting
point of an intussusception. Benign diverticula should be removed as incidental procedures unless contraindicated by a potentially complicating disease
elsewhere in the abdomen. ese congenital anomalies are remnants of the
embryonic omphalomesenteric duct arising from the midgut, are found in
to percent of patients, principally males, and are located usually to cm
above the ileocecal valve. e terminal ileum should be routinely examined
for a Meckel’s diverticulum as part of a thorough abdominal exploration.
PREOPERATIVE PREPARATION Preoperative preparation is devoted chie y
to the restoration of blood, uids, and electrolytes. Nasogastric suction is
advisable in the presence of obstruction or peritonitis, which may require
additional blood, plasma, and antibiotics.
ANESTHESIA General inhalation anesthesia is preferred; however, spinal
or local anesthesia may be indicated under special circumstances.
POSITION e patient is placed in a comfortable supine position.
OPERATIVE PREPARATION e skin is prepared with antiseptic, then
draped with towels or an adhesive plastic drape. A large sterile laparotomy
sheet completes the draping.
INCISION AND EXPOSURE A midline incision is preferred because of its
maximum exibility. However, incidental excision of a Meckel’s diverticulum may be performed through any incision that exposes it.
DETAILS OF PROCEDURE e segment of the terminal ileum involved
with the Meckel’s diverticulum is delivered into the wound by Babcock
M’ D
forceps for stabilization. e Meckel’s diverticulum may be as far as
to cm back from the level of the ileocecal valve. If a mesodiverticulum
is present, it should be freed, divided between hemostats, and ligated as
a mesoappendix (figure 1). If the diverticulum has quite a wide neck,
it may be excised either by oblique or cross clamping of the base, by
wedge or V-shaped excision of the base, or by segmental resection of
the involved ileum with end-to-end anastomosis (figure 2). e base is
double clamped with noncrushing Potts-type clamps in a direction transverse or diagonally across to the bowel. e specimen is excised with a
scalpel. Traction sutures, A and B, of silk are placed to approximate the
serosal surface of the intestinal wall just beyond either end of the incision
(figure 3). When tied, these sutures, A and B, serve to stabilize the intestinal wall during the subsequent closure. Sutures of silk are placed at
either end of the incision, and a row of interrupted silk horizontal mattress sutures is placed beneath the clamp (figure 4). e clamp
is then removed, the sutures tied, and any excess intestinal wall excised.
en an inverting layer of interrupted silk horizontal mattress
sutures is placed (figures 5 and 6). e patency of the lumen is then
tested between the surgeon’s thumb and index nger (figure 7). Alternatively, some surgeons prefer to amputate the diverticulum with a stapling instrument. e diverticular mesentery is divided and its vessels are
ligated, as in figure 1. e diverticulum is splayed transversely to the axis
of the bowel using a pair of stay sutures at either side. A linear stapling
device (GIA) may be used, according to the surgeon’s preference. A er
removal of the diverticulum, the transverse staple line is then inverted
with a series of silk mattress sutures. Again, the patency and integrity
of the suture line is tested by the surgeon.
CLOSURE e usual laparotomy closure is performed.
POSTOPERATIVE CARE Postoperative care is similar to that for appen-
dectomy or small bowel anastomosis. Fluid and electrolyte balance is
maintained intravenously until intestinal motility returns. e nasogastric
tube is then removed and progressive alimentation begun. Any subsiding
in ammation, peritonitis, or drained abscess is treated with the appropriate
systemic antibiotics plus blood and plasma replacement. e major postoperative complications are obstruction, peritonitis, and wound infection,
which may require further appropriate surgical therapy. ■
124
Incision
2
Incision
Diverticulum
3
1
A
Alternate Procedures
A
Diverticulum
Incision
B
4
Inner layer of mattress sutures
B
A
A
5
Outer layer of inverting
horizontal mattress sutures
B
6
7
A
B
Inverting closure
A
125
PLATE
54
INDICATIONS Acute appendicitis is a bacterial process that is usually pro-
gressive; however, the many locations of the appendix allow this organ to
mimic many other retrocecal, intra-abdominal, or pelvic diseases. When
the diagnosis of acute appendicitis is made, prompt operation is almost
always indicated. Delay for administration of parenteral uids and antibiotics may be advisable in toxic patients, children, or elderly patients.
If the patient has a mass in the right lower quadrant when rst seen,
several hours of preparation may be indicated. O en a phlegmon is present and appendectomy can be accomplished. When an abscess is found, it
is drained and appendectomy performed concurrently, if this can be done
easily. Otherwise, the abscess is drained and an interval appendectomy is
carried out at a later date.
If the diagnosis is chronic appendicitis, then other causes of pain and
sources of pathology should be ruled out.
PREOPERATIVE PREPARATION e preoperative preparation is devoted
chie y to the restoration of uid balance, especially in the very young and
in aged patients. e patient should be well hydrated, as manifest by a good
urine output. A nasogastric tube is passed for decompression of the stomach so as to minimize vomiting during induction of anesthesia. Antipyretic
medication and external cooling may be needed since hyperpyrexia complicates general anesthesia. If peritonitis or an abscess is suspected, antibiotics are given.
ANESTHESIA Inhalation anesthesia is preferred; however, spinal anesthe-
sia is satisfactory. Local anesthesia may be indicated in the very ill patient.
POSITION e patient is placed in a comfortable supine position.
OPERATIVE PREPARATION e skin is prepared in the usual manner.
INCISION AND EXPOSURE In no surgical procedure has the practice of
standardizing the incision proved more harmful. ere can be no incision
that should always be utilized, since the appendix is a mobile part of the
body and may be found anyplace in the right lower quadrant, in the pelvis,
up under the ascending colon, and even, rarely, on the le side of the peritoneal cavity (figures 2 and 3). e surgeon determines the location of the
appendix, chie y from the point of maximum tenderness by physical examination, and makes the incision best adapted for exposing this particular
area. e great majority of appendices are reached satisfactorily through
A
the right lower muscle-splitting incision, which is a variation of the original
McBurney procedure (figure 1, incision A). If the patient is a woman and
laparoscopic evaluation is not available, many surgeons prefer a midline
incision to permit exposure of the pelvis. If there is evidence of abscess formation, the incision should be made directly over the site of the abscess.
Wherever the incision is, it is deepened rst to the aponeurosis of the
outer layer of muscle. In the muscle-splitting incision the aponeurosis of
the external oblique is split from the edge of the rectus sheath out into the
ank parallel to its bers (figure 4). With the external oblique held aside
by retractors, the internal oblique muscle is split parallel to its bers up to
the rectus sheath (figure 5) and laterally toward the iliac crest (figure 6).
Sometimes the transversalis fascia and muscle are divided with the internal
oblique, but a stouter structure for repair results if the transversalis fascia
is opened with the peritoneum. e rectus sheath may be opened for or
cm to give additional exposure (figure 7). e peritoneum is picked up
between forceps, rst by the operator and then by the assistant (figure 8).
e operator drops the original bite, picks it up again close to the forceps
of the rst assistant, and compresses the peritoneum between the forceps
with the handle of the scalpel to free the underlying intestine. is maneuver
to safeguard the bowel is important and should always be carried out before
opening the peritoneum. As soon as the peritoneum is opened (figure 8),
its edges are clamped to the moist gauze sponges already surrounding the
wound (figure 9). Cultures are taken of the peritoneal uid.
DETAILS OF PROCEDURE As a rule, if the cecum presents almost immedi-
ately, it is better to pull it into the wound, to hold it in a piece of moist gauze,
and to deliver the appendix without feeling around blindly in the abdomen
(figure 10). e peritoneal attachments of the cecum may require division
to facilitate the removal of the appendix. Once the appendix is delivered,
its mesentery near the tip may be seized in a clamp, and the cecum may
be returned to the abdominal cavity. Following this, the peritoneal cavity
is walled o with moist gauze sponges (figure 11). e mesentery of the
appendix is divided between clamps, and the vessels are carefully ligated
(figure 12). It is better to apply a trans xing suture rather than a tie to the
contents of the clamps, for when structures are under tension, the vessels
not infrequently retract from the clamp and bleed later into the mesentery.
With the vessels of the mesentery tied o , the stump of the appendix is
crushed in a right-angle clamp (figure 13).
CONTINUES
126
1
Incision A
Right
rectus muscle
4
2
Incision B
5
Aponeurosis of
external oblique muscle
Ileocolic fold
Anterior taenia
External oblique
Ileocolic
artery
Appendiceal
artery
Ileocecal fold
Appendix
Mesoappendix
Rectus sheath
3
F
H
G
E
D
C
Pelvic brim
6
I
A
B
Peritoneum
and
transversalis
fascia
Internal
oblique muscle
7
Internal
oblique
10
Peritoneum and
transversalis fascia
Rectus muscle
Ileocecal fold
Terminal
ileum
Rectus
sheath
11
Internal oblique
8
Gauze walling
off intestines
Ileum
Peritoneum and
transversalis fascia
9
12
Anterior taenia
leading to appendix
Cecum
13
Mesoappendix
Anterior taenia
Appendix
Appendiceal
artery
Mesoappendix
127
Right
angle
forceps
Ligated
mesoappendix
PLATE
55
DETAILS OF PROCEDURE e right-angle clamp is moved
cm toward the tip of the appendix. Just at the proximal edge of the crushed
portion, the appendix is ligated (figure 14) and a straight clamp is placed
on the knot. A purse-string suture is laid in the wall of the cecum at the base
of the appendix, care being taken not to perforate blood vessels where the
mesentery of the appendix was attached (figure 15). e appendix is held
upward; the cecum is walled o with moist gauze to prevent contamination;
and the appendix is divided between the ligature and clamp (figure 16). e
suture on the base of the appendix is cut and pushed inward with the straight
clamp on the ligature of the stump to invaginate the stump into the cecal
wall. e jaws of the clamp are separated, and the clamp is removed as the
purse-string suture is tied. e wall of the cecum may be xed with tissue forceps to aid in inverting the appendiceal stump (figure 17). e cecum then
appears as shown in figure 18. e area is lavaged with warm saline and the
omentum is placed over the site of operation (figure 19). If there has been a
localized abscess or a perforation near the base, so that a secure closure of the
cecum is not possible, or if hemostasis has been poor, drainage may be advisable. Drains should be so and smooth, preferably a silastic sump one. On no
occasion should dry gauze or heavy rubber tubing be used, since these may
cause bowel injury. Some surgeons do not drain the peritoneal cavity in the
presence of obvious peritonitis that is not localized, relying upon peritoneal
irrigation, parenteral antibiotic, and systemic antibiotic therapy to control it.
If the appendix is not obviously involved with acute in ammation, a
more extensive exploration is mandatory. In the presence of peritonitis without involvement of the appendix, the possibility of a ruptured peptic ulcer
or sigmoid diverticulitis must be ruled out. Acute cholecystitis, regional
ileitis, and involvement of the cecum by carcinoma are not uncommon possibilities. In the female, the possibility of bleeding from a ruptured graa an
follicle, ectopic pregnancy, or pelvic infection is ever present. Inspection of
the pelvic organs under these circumstances cannot be omitted. On occasion a Meckel’s diverticulum will be found. Closure of the abdomen, with
subsequent study and adequate preparation for bowel resection at a later
date, may be indicated.
CLOSURE e muscle layers are held apart while the peritoneum is closed
with a running or interrupted absorbable suture (figure 19). Transversalis
fascia incorporated with the peritoneum o ers a better foundation for the
suture. Interrupted sutures are placed in the internal oblique muscle and in
the small opening at the outer border of the rectus sheath (figure 20). e
external oblique aponeurosis is closed but not constricted with interrupted
sutures (figure 21). e subcutaneous tissue and skin are closed in layers.
e skin may be le open for a delayed secondary closure if pus is found
about the appendix.
A
ALTERNATIVE METHOD
In some instances, in order to avoid rupturing a distended acute appendix,
it is safe to ligate and divide the base of the appendix before attempting
to deliver the appendix into the wound. For example, if the appendix is
adherent to the lateral wall of the cecum (figure 22), it is occasionally
simpler to pass a curved clamp beneath the base of the appendix in order
that it may be doubly clamped and ligated (figure 23). Following ligation
of the base of the appendix, which is o en quite indurated, it is divided
with a knife (figure 24). e base of the appendix is then inverted with a
purse-string suture (figures 25 and 26). e attachments of the appendix
are divided with long, curved scissors until the blood supply can be clearly
identi ed (figure 27). Curved clamps are then applied to the mesentery
of the appendix, and the contents of these clamps are subsequently ligated
with sutures (figure 28).
When the appendix is not readily found, the search should follow the
anterior taenia of the cecum, which will lead directly to the base of the
appendix regardless of its position. When the appendix is found in the retrocecal position, it becomes necessary to incise the parietal peritoneum
parallel to the lateral border of the appendix as it is seen through the peritoneum (figure 29). is allows the appendix to be dissected free from its
position behind the cecum and on the peritoneal covering of the iliopsoas
muscle (figure 30).
On occasion the cecum may be in the upper quadrant or indeed on the
le side of the abdomen when failure of rotation has occurred. A liberal
increase in the size of the incision and even a second incision may be, on
occasion, good judgment.
POSTOPERATIVE CARE e uid balance is maintained by the intrave-
nous administration of Ringer’s lactate. e patient is permitted to sit up
for eating on the day of operation, and he may get out of bed on the rst
postoperative day. Sips of water may be given as soon as nausea subsides.
e diet is gradually increased.
If there has been evidence of peritoneal sepsis, frequent doses of antibiotics are administered. Constant gastric suction is advisable until all evidence
of peritonitis and abdominal distention has subsided. Accurate estimate of
the uid intake and output must be made.
Pelvic localization of pus is enhanced by placing the patient in a semisitting
position. e patient is allowed out of bed as soon as his general condition
warrants. Prophylaxis against deep venous thrombosis is instituted. In the
presence of persistent signs of sepsis, wound infection and pelvic or subphrenic abscess should be considered. In the presence of prolonged sepsis,
serial computed tomography (CT) imaging scans beginning about days
a er surgery may reveal the causative site. ■
128
14
15
16
Forceps
on taenia
17
18
21
Ligation
of base
19
Omentum
Peritoneum
End of
pursestring
suture
External oblique muscle
and
transversalis
fascia
Purse-string suture
Paracecal Adherent Appendix
22
Appendix
External oblique
20
Internal
oblique muscle
Invagination
of stump
Anterior
rectus sheath
23
Internal
oblique muscle
24
28
Clamp on mesoappendix
Distal stump
25
Terminal ileum
Purse-string suture
Retrocecal appendix
29
Incision
Parietal
peritoneum
Appendix
26
Cecum
Taenia
Adhesions
Terminal
ileum
Appendix
Iliopsoas
muscle
27
Mesoappendix
30
129
PLATE
56
INDICATIONS Acute appendicitis is a clinical diagnosis, the accuracy of which
has improved with modern diagnostic imaging techniques including CT scan of
the abdomen and pelvis, which has an accuracy of or more. e diagnosis is
made using a combination of history, physical examination, and laboratory tests
plus an elevated temperature and white blood cell count. A positive imaging
study is helpful and gives reassurance about the diagnosis. In equivocal cases,
serial observations and studies over time improve the accuracy of diagnosis, but
at the risk of an increasing rate of perforation.
Laparoscopic appendectomy is appropriate for virtually all patients and is preferred in obese patients, who require longer open incisions with increased manipulation and the resultant increase in surgical-site infections. e laparoscopic
technique is also indicated in females, especially during the reproductive years,
when tubal and ovarian pathology may mimic appendicitis. Laparoscopy not only
provides direct observation of the appendix but also allows evaluation of all intraabdominal organs, especially those in the female pelvis. Laparoscopic appendectomy has been shown to be as safe as open appendectomy in the rst trimester
of pregnancy; however, there is always risk to the fetus with any anesthesia or
operation. Later or third-trimester pregnancies as well as any process that creates
intestinal distention will make entering the intraperitoneal space more di cult
and leave no room for maneuvering the instruments for a safe operation. Finally,
laparoscopic appendectomy results in less incisional pain a er surgery, allows a
faster return to normal function or work, and produces a better cosmetic result.
PREOPERATIVE PREPARATION As healthy youngsters and young adults
constitute the most common population with appendicitis, the usual preoperative evaluation for anesthesia and surgery is performed. Intravenous uids for
hydration and preoperative antibiotics are given. Extra time may be needed in
the very young or old for correction of electrolyte and uid imbalances. Hyperpyrexia should be treated with antipyretics or even external cooling, so as to lessen
the risk of general anesthesia. Additional discussion concerning preparation is
contained in the discussion accompanying Plate .
ANESTHESIA General anesthesia with placement of an endotracheal tube is
preferred. A er induction, an orogastric tube may be placed by the anesthesiologist. is tube is removed before the end of the case or is replaced with a
nasogastric tube if prolonged decompression is anticipated.
POSITION e patient is placed in a supine position. e right arm may be
extended for intravenous and blood pressure cu access by the anesthesiologist
while the le arm with the pulse oximeter is tucked in at the patient’s side. is
allows for easier movement by the surgeon and the assistant operating the videoscope. e beroptic light cable and gas tubing are usually placed to the head
of the table; the video monitor is placed across from the operating team; and the
electrocautery and suction irrigator are placed toward the foot of the table, where
the scrub nurse and Mayo instrument tray are positioned.
OPERATIVE PREPARATION A Foley catheter is usually placed and the abdo-
men is prepped in the routine manner.
DETAILS OF PROCEDURE A typical placement for access ports is shown at
the umbilicus, le lower quadrant, and lower midline (figure 1). Some surgeons
prefer a right-upper-quadrant port instead of the one in the le lower quadrant.
As in most laparoscopic procedures, some form of triangulation is employed,
with the longest and widest angle given to the operating ports and instruments.
e videoscope port is created rst. Although some use an initial in ation of the
abdomen with a Veress needle (see Plate ), most general surgeons employ the
open Hasson technique (see Plate ). e surgeon may enter at the superior or
inferior margin of the umbilicus with either a vertical or semicircular transverse
incision. A er the Hasson port is placed and secured with the stay sutures, the
abdomen is in ated with CO
(≤ mmHg) and ow rate while he or she monitors the actual intra-abdominal
pressure and the total volume of gas insu ated. e abdomen then enlarges and
becomes tympanitic.
e videoscope is attached to the telescopic instrument, which may be
straight (zero degree) or angled. e system is white-balanced and the focus
adjusted. A er the optical end of the instrument has been cleaned with antifog
solution, it is introduced down the Hasson port. A careful visualization of all
four quadrants of the abdomen is performed and a record is made of all normal
and abnormal ndings.
Under direct vision with the videoscope, two additional -mm ports are put
into the abdomen. One is in the le lower quadrant and is placed lateral to the
rectus muscle with its epigastric vessels. e light of the videoscope is used
to transilluminate the abdominal wall at the proposed site so as to avoid trocar placement through vessels in the oblique muscles. e surgeon in ltrates
the -mm site with local anesthetic. is in ltrating needle can be advanced
through the abdominal wall and the videoscope will see the needle enter the
anticipated site for this port. A -mm skin incision is made and the subcutaneous tissue dilated with a small hemostat down to the level of the fascia. e
-mm port is placed through the abdominal wall while the surgeon views the
A, L
. e surgeon sets the maximum gas pressure
safe entrance of the pointed trocar into the intraperitoneal space. e third port
is placed through the midline linea alba in a suprapubic position so as to avoid
the bladder, which has been decompressed with a Foley catheter. e strategy
for a widely spread (hand’s breadth) triangular pattern of port placement now
becomes apparent as the three instruments complete for room to maneuver.
e patient is placed in the Trendelenburg position and the right side of the
operating table may be elevated using gravity to hold the small bowel away from
the right lower quadrant. If a normal appendix is found, a search for other in ammatory processes is begun. Tubo-ovarian diseases, in ammatory bowel disease,
and Meckel’s diverticulitis are most commonly found. Once the diagnosis of
appendicitis is established, the appendix is mobilized. e appendix and its mesentery must be clearly visualized. e position of the appendix is quite variable,
and it may be covered with peritoneum or even the cecum (
ing of any peritoneal covering or the equivalent of the lateral line of Toldt along the
cecum may require placement of an additional operating port. If the surgeon cannot obtain complete visualization of the appendix, mesoappendix, and base of the
cecum for a safe transection, the operation is converted to an open procedure.
Laparoscopic removal begins with a splaying out of the mesoappendix using a
grasping forceps upon the mesentery (figure 3). e in amed tip of the appendix
is not grasped, as this could cause it to rupture. e surgeon opens through the
mesentery at the base of the appendix using a dissecting instrument. If maneuvering of the appendix and its mesentery is di cult using the grasping forceps, some
surgeons prefer to lasso the in amed end of the appendix with a loop suture that is
applied snugly. e cut end of this suture may be grasped more securely with the
maneuvering forceps (figure 4). e mesoappendix is divided (figure 4) in one
or more transections using a endoscopic vascular stapling instrument that is passed
through the large Hasson port. is assumes that a -mm videoscope is available
for use through the le -lower-quadrant port. Otherwise, the le -lower-quadrant
port is enlarged to mm, as both the videoscope and endoscopic vascular stapler
require large ports. e base of the appendix is divided with the endoscopic cutting
linear stapler (endo GIA) (figure 5). An important maneuver with any division
using this stapler is to rotate it about degrees, so as to visualize the entire length
and the contents within its jaws. is rotation should also be done during the
stapling of the mesoappendix (figure 5A).
A small, minimally in amed appendix can be removed safely through the
sha of a -mm port. Most surgeons place an enlarged or suppurative appendix into a plastic bag for removal through the abdominal wall (figure 6). is
lessens the chances of infection at the surgical site. e appendiceal stump and
stapled mesoappendix are inspected for security and hemostasis. e area is
lavaged with the suction irrigator and a regional inspection is made to verify
the integrity of the cecum and small bowel.
Each of the -mm ports is removed under direct vision with the videoscope
to make sure that there are no bleeding abdominal wall vessels.
CLOSURE e abdomen is decompressed and the Hasson port removed. Rou-
tinely, only the -mm port sites require fascial closure. Some surgeons tie the
stay sutures together if this provides a secure closure to inspection and nger
palpation. Others place new delayed absorbable sutures through the fascia
for its closure. Scarpa’s fascia and the subcutaneous fat are not closed. e skin
is approximated with ne absorbable sutures. Adhesive skin strips and dry
sterile dressings (Band-Aid bandages) are applied.
POSTOPERATIVE CARE The orogastric tube is removed before the patient
awakens from anesthesia. e Foley catheter is discontinued as soon as the
patient is alert enough to void. If a long-acting local anesthetic was used at the port
sites, postoperative pain can be controlled with oral medications. ere may
be some transient nausea, but most patients can be weaned from intravenous
uid to simple oral intake within a day. Antibiotic therapy is o en perioperative but may continue for a few days, depending on the operative ndings. Most
patients are discharged home within a day or two.
ALTERNATIVE METHODS ere are many variations upon the technique
described above. ese involve the placement of the ports and the methods for
transecting the appendix and mesoappendix.
Virtually all laparoscopic appendectomies begin with placement of the videoscope through an umbilical site. Insu ation using the Veress needle technique is preferred by some, although most general surgeons enter the abdomen
in a more controlled, open manner using the Hasson technique. Placement of
additional ports is determined by the surgeon’s preference. In general, the sites
should be widely spaced to avoid instrument competition. e size of the second port is a function of whether or not the surgeon has a -mm videoscope
and whether he or she plans to use () the vascular stapler or () large ultrasonic, cautery, or laser devices for transection and hemostasis. Most of these
devices currently require a -mm port.
Alternatively, some surgeons use metal clips for transection of the mesoappendix and a pair of absorbable loop sutures for occlusion of the stump of the appendix, whose mucosal center is cauterized. However, vascular staples are preferred
by most for their security and the avoidance of unrecognized thermal damage. ■
figure 2). Safe open-
130
5A
6
131
PLATE
57
Several important anatomic facts in uence the technique of surgery in the
large intestine. As a consequence of its embryologic development, the colon
has two main sources of blood supply. e cecum, ascending colon, and
proximal portion of the transverse colon are supplied with blood from the
superior mesenteric artery, while the distal transverse colon, splenic exure, descending colon, sigmoid, and upper rectum are supplied by branches
of the inferior mesenteric artery (see gure).
Advantage may be taken of the free anastomotic blood supply along the
medial border of the bowel by dividing either the inferior mesenteric artery
or the middle colic artery and by depending upon the collateral circulation
through the marginal artery of Drummond to maintain the viability of a
long segment of intestine. e peritoneal re ection on the lateral aspect of
the colon is practically bloodless, except at the exures or in the presence
of ulcerative colitis or portal hypertension, and may be completely incised
without causing bleeding or jeopardizing the viability of the bowel. When
the lateral peritoneum is divided and the greater omentum freed from the
transverse colon, extensive mobilization is possible, including derotation
of the cecum into the right or le upper quadrant. Care should be taken to
avoid undue traction on the splenic exure lest attachments to the capsule
of the spleen be torn and troublesome bleeding occur. In the presence of
malignancy of the transverse colon, the omentum is usually resected adjacent to the blood supply of the greater curvature of the stomach.
A er the colon has been freed from its attachments to the peritoneum
of the abdominal wall, the exures, and the greater omentum, it can be
drawn toward the midline through the surgical incision limited only by the
length of its mesentery. is mobility of the colon renders the blood supply
more accessible and o en permits a procedure to be performed outside the
peritoneal cavity. e most mobile part of the large bowel is the sigmoid,
because it normally possesses a long mesentery, whereas the descending
colon and right half of the colon are xed to the lateral abdominal wall.
e lymphatic distribution of the large bowel conforms to the vascular supply. Knowledge of this is of great surgical importance, especially in
the treatment of malignant neoplasm, because an adequate extirpation of
potentially involved lymph nodes requires the sacri ce of a much larger
portion of the blood supply than would at rst seem essential. e lymphatic spread of carcinoma of the large intestine along the major vascular supply has been responsible for the development of classic resections.
Local “sleeve” resection for malignancy may be indicated in the presence of
metastasis or because of the patient’s poor general condition.
When a curative resection is planned, the tumor and adjacent bowel
must be su ciently mobilized to permit removal of the immediate lymphatic drainage area.
Basically, the resections of the colon should include either the lymphatic
drainage area of the superior mesenteric vessels or that of the inferior mesenteric vessels. While this would approach the ideal, experience has shown
that approximately four types of resections are commonly performed:
right colectomy, le colectomy, anterior resection of the rectosigmoid, and
abdominoperineal resection. For years lesions of the cecum, ascending
colon, and hepatic exure have been resected by a right colectomy with
ligation of the ileocolic, right colic, and all or part of the middle colic vessels
(A). Lesions in the cecal area may be associated with involved lymph glands
along the ileocolic vessels. As a result, a segment of the terminal ileum is
commonly resected along with the right colon. Lesions in the region of the
splenic exure are in the one area where le colectomy by a sleeve resection
may be performed. Extensive resections can be carried out with good assurance of an adequate blood supply, since the marginal vessels are divided
nearer their points of origin. In addition to the marginal vessels, the le
colic artery near its point of origin and the inferior mesenteric vein are
ligated even before manipulation of the tumor is carried out to minimize
the venous spread of cancer cells. End-to-end anastomosis without tension
can be accomplished by freeing the right colon of its peritoneal attachments
and derotating the cecum back to its embryologic position on the le side.
S A L I
e blood supply is sustained through the middle colic vessels and the
sigmoidal vessels. Although the veins tend to parallel the arteries, this is
not the case with the inferior mesenteric vein. is vein courses to the le
before it dips beneath the body of the pancreas to join the splenic vein (B).
Lesions of the lower descending colon, sigmoid, and rectosigmoid may
be removed by an anterior resection. e inferior mesenteric artery is
ligated at its point of origin from the aorta (C) or just distal to the origin
of the le colic artery. e upper segment for anastomosis will receive its
blood supply through the marginal arteries of Drummond from the middle
colic artery. e viability of the rectosigmoid is more uncertain following
the ligation of the inferior mesenteric artery. Accordingly, the resection is
carried low enough to ensure a good blood supply from the middle and
inferior hemorrhoidal vessels. is level is usually so low that the anastomosis must be carried out in the pelvis anterior to the sacrum. Here again
the principle of mobilizing the exures as well as the right colon may be
required to ensure an anastomosis without tension.
e most extensive resection involves lesions of the low rectosigmoid,
rectum, and anus. High ligation of the inferior mesenteric vessels and ligation of the middle and inferior hemorrhoidal vessels, along with wide excision of the rectum and anus, are required. Since the lymphatic drainage to
the anus and lower rectum may drain laterally even to the inguinal region,
wide lateral excision of low-lying rectal and anal neoplasms is mandatory.
In order to minimize the possibilities of tumor spread, the lesion should
be covered with gauze as early in the procedure as possible. Further isolation
should be provided by ligation of the colon above as well as below the tumor
with gauze or umbilical tapes. Likewise, early ligation of the vascular supply
should be performed before manipulation of the tumor is carried out.
Since bowel anastomosis must be performed in the absence of tension,
it is imperative that considerable mobilization of the colon, especially of
the splenic exure, be carried out if continuity is to be restored following
extensive resection of the le colon. e presence of pulsating vessels adjacent to the mesenteric margin, which has been cleared preparatory to the
anastomosis, should be assured. Injection of procaine into the adjacent
mesentery will sometimes enhance arterial pulsation. Occasionally, pulsations are not apparent since the middle colic artery is compressed as a result
of the small bowel’s being introduced into a plastic bag and displaced to the
right and outside of the abdominal wall. e Doppler apparatus may be
used to verify the adequacy of the blood supply.
e large intestine bears an important relation to a number of vital
structures. us, in operations on the right half of the colon, the right ureter and its accompanying vessels are encountered behind the mesocolon.
e duodenum lies posterior to the mesentery of the hepatic exure and is
always exposed in mobilizing this portion of the bowel. e spleen is easily
injured in mobilizing the splenic exure. e le ureter and its accompanying spermatic or ovarian vessels are always encountered in operations on
the sigmoid and descending colon. In an abdominoperineal resection of
the rectum, both ureters are potentially in danger of injury. e surgeon
must not only be aware of these structures, but must positively identify
them before dividing the vessels in the mesentery of the colon.
e anatomic arrangement of the colon that permits mobilization of
low-lying segments sometimes tempts the surgeon to reconstruct the normal continuity of the fecal current without adequate extirpation of the
lymphatic drainage zones. Extensive block excision of the usual lymphatic
drainage areas, combined with excision of a liberal segment of normalappearing bowel on either side of a malignant lesion, is mandatory. Primary
anastomosis of the large intestine requires viable intestine, the absence of
tension, especially when the bowel becomes distended postoperatively, and
a bowel wall of near-normal consistency. Although the danger from sepsis
has decreased substantially in recent years, the fact remains that the surgical
problems concerned with the large intestine are o en complex and require
more seasoned judgment and experience than does almost any other eld
in general surgery. ■
132
Соседние файлы в папке Библиотека им академика М.И. Перельмана