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_1498_Библиотеки_им_академика_М_И_Перельмана.pdf
93
8. Strangulated Inguinal Hernia
might be suggested by pneumatosis intestinalis, fat stranding, or even
free air within the hernia sac.
Reduction of a tender inguinal hernia can be judiciously attempted,
especially if the incarceration occurred within a few hours of presentation.
However, even reduced hernia contents remain at risk for strangulation if
the hernia is reduced en masse. Reduction of strangulated contents can
be dangerous since the liberated organ may elaborate in fl ammatory
mediators or even succus entericus due to perforation; therefore, forced
reduction of potentially strangulated contents should be avoided. In the
case of either an acutely tender incarcerated hernia or a strangulated
hernia, immediate operation is indicated.
Operative Approaches
The principles for management of strangulated inguinal hernias are
the same regardless of approach: reduction of the hernia contents,
inspection of the contents to assess viability, resection of necrotic organs,
and repair of the defect. This can be accomplished via an anterior
approach, an open preperitoneal approach, or laparoscopically via either
a transabdominal or totally extraperitoneal approach.
Strangulated inguinal hernias may be managed using a standard
anterior groin incision and repair. After dividing the fascia of the external
oblique muscle, the hernia sac will be encountered. The sac should be
carefully opened and the hernia contents inspected for viability. If
necrotic bowel is discovered, a resection may be performed through the
same incision, rather than performing a laparotomy. A tension-free repair
Fig. 8.2. CT scan showing evidence of obturator hernia with surrounding fl uid,
fat stranding, and tissue edema.
94
J.P. Pearl and E.M. Ritter
will yield the lowest recurrence rate, but there is a concern for mesh
infection in the contaminated fi eld. However, there are several studies
describing the safe use of polypropylene mesh for the Lichtenstein repair
of strangulated hernias. A biologic mesh may also be an option which
may minimize the risk of mesh infection.
On occasion, hernia contents may be dif fi cult to reduce via the
anterior approach. In this case, after the hernia sac has been opened and
the contents inspected, the defect may need to be expanded to allow
reduction of the incarcerated contents. For indirect hernias, the deep
inguinal ring should be incised medially to avoid injury to the external
spermatic artery or vas deferens. Care must be taken to ensure the inferior
epigastric vessels are properly ligated to avoid hemorrhagic complication.
For direct hernias, a division of the transversalis fascia either medially or
laterally may be required. Extensive lateral division also requires
awareness of the inferior epigastrics. For femoral hernias, the lacunar
ligament may be divided medially or the iliopubic tract superiorly.
Laterally, the external iliac vessels prevent extensive dissection.
Induction of general anesthesia may result in spontaneous reduction
of incarcerated or strangulated hernia contents. The risk of reduction en
masse or reduction of compromised bowel exists; thus, the intra-
abdominal contents must be explored. This can be accomplished via low-
midline laparotomy or, less invasively, using the laparoscope. A trocar
can be inserted through the hernia sac into the abdominal cavity. With the
sac secured tightly around the trocar, a pneumoperitoneum can be
established. A laparoscopic peritoneal access site remote from the groin
may also be chosen with the added bene fi t of being able to plan further
incisions based on the fi ndings. The laparoscope will allow visualization
of the abdominal contents. If ischemic bowel is encountered, it can be
resected via either laparotomy or via laparoscopic techniques.
Malangoni and Condon fi rst described the preperitoneal repair of
strangulated inguinal hernias in 1986. A transverse skin incision is made
2 cm cephalad to the anticipated location of the external inguinal ring.
The external oblique, internal oblique, and transversus abdominis
muscles are incised, and the preperitoneal space is entered. From this
approach, the hernia contents can be easily inspected, resection can be
performed, if necessary, and the hernia defect can be repaired. Either a
Cooper’s ligament or iliopubic tract repair was originally used, but today,
a prosthetic might be chosen.
The Henry operation uses a midline infraumbilical incision to access
the preperitoneal space. The linea alba is divided below the umbilicus,
and the retrorectus space is entered. Below the semilunar line, the
95
8. Strangulated Inguinal Hernia
retrorectus space and the preperitoneal space are con fl uent. Strangulated
hernia contents are resected after opening the peritoneum and controlling
the necrotic bowel. Repair of the defect was originally described using a
tissue repair, but a prosthetic may be a better choice.
Both the transabdominal preperitoneal (TAPP) and the totally
extraperitoneal (TEP) laparoscopic repairs have been described for
managing incarcerated and strangulated inguinal hernias. Incarcerated
inguinal, femoral, and obturator hernias can be approached with the
laparoscope. For the TAPP, the abdomen is entered at the umbilicus.
Reduction of the hernia contents often requires incision of the hernia ring.
For indirect hernias, the ring is incised in a ventrolateral direction to avoid
the vas deferens and testicular vessels. For direct and femoral hernias, the
ring is enlarged using a ventromedial incision to avoid the femoral vessels.
The transabdominal laparoscopic repair affords an optimal view of
intra-abdominal contents to assess viability of the incarcerated organs. If
ischemic bowel is encountered, it should not be immediately resected.
Assessing bowel viability is usually based on the subjective appearance
of the bowel (Figs. 8.3 and 8.4 ). The bowel can be observed for several
minutes to assess for improvement in ischemia following hernia reduction.
Signs of resolving ischemia can include improvements in color, regaining
normal caliber, and return of visible peristalsis. If the viability is still in
question after a period of observation, the bowel may be left in situ and a
second-look laparoscopy could be planned for the next 24–72 h. In cases
of strangulated small bowel obstructions, second-look laparoscopy has
been shown to be safe and can prevent a bowel resection in some patients.
Fig. 8.3. Characteristics of ischemic but ultimately viable bowel from a strangulated
inguinal hernia. Note the uniform red discoloration. This bowel also demonstrated
peristalsis on inspection.
96
J.P. Pearl and E.M. Ritter
Second-look laparoscopy may be useful in the case of strangulated groin
hernias. If the reduced hernia contents are viable or become clearly viable
after reduction, repair can proceed via either a TAPP or TEP approach. If
the bowel remains ischemic after reduction and hernia repair, it should be
resected. This can be accomplished totally laparoscopically or a small
directed laparotomy may be performed (Fig. 8.5 ).
Many surgeons prefer the totally extraperitoneal approach for inguinal
hernia repair. The TEP repair affords access to all of the hernia ori fi ces but
does not allow the same inspection of the hernia contents as the TAPP.
An advantage of the TEP over the TAPP repair is the maintenance of an
intact peritoneum to protect the prosthetic from potential contamination.
A meta-analysis of TAP and TEPP in incarcerated and strangulated hernias
has shown no difference in rates of mesh infection or contamination.
A combined transabdominal and extraperitoneal laparoscopic approach
may be ideal. The peritoneal space can be entered either at the umbilicus
or the subcostal region. One or two additional trocars may be needed to
reduce the hernia contents and inspect their viability. Immediate resection
is not recommended unless full thickness necrosis and perforation is
present. The trocars can be left in place after evacuation of the
pneumoperitoneum and a TEP repair performed using standard techniques.
Access to the preperitoneal space can be gained at the umbilicus even if
this site was used for initial access to the peritoneal space. Lateral
dissection through the same infraumbilical skin incision will expose the
anterior rectus sheath. Incision of the anterior sheath with lateral retraction
Fig. 8.4. Example of necrotic small bowel from a strangulated inguinal hernia.
Note the areas of deep purple discoloration and the areas of blanching serosa.
The grasper on the left is controlling spillage from an area of perforation.
97
8. Strangulated Inguinal Hernia
of the underlying rectus muscle will allow access to the preperitoneal
space well below the level of the initial intraperitoneal trocar. Care should
be used to avoid puncture of the peritoneum during groin dissections as
this eliminates the potential protection of the mesh provided by an intact
peritoneum. At the completion of the TEP, the pneumoperitoneum can be
reestablished and the abdominal contents reinspected.
An alternative is to perform the extraperitoneal portion of the hernia
repair initially. A standard TEP can be performed with reduction of the
incarcerated contents. To adequately inspect the bowel, the abdomen can
be entered through the infraumbilical incision after the conclusion of the
TEP. Additional transabdominal trocars might be necessary to manipulate
the intra-abdominal structures. This approach is best employed when the
suspicion of the presence of necrotic contents is low.
Choice of Prosthetic
The controversy around the choice of prosthetic for repair of
strangulated hernias begins with the decision as to whether or not to use
a prosthetic material at all. Additionally, if a prosthetic repair is chosen,
Fig. 8.5 Transperitoneal laparoscopic exploration allows for a minimized and
planned laparotomy well away from the groin. This should minimize the chance
for local contamination in the area of the prosthetic mesh repair.
98
J.P. Pearl and E.M. Ritter
which of the overwhelming prosthetic mesh options should be used?
A variety of patient and prosthetic factors can help guide this decision-
making process. The fi rst and most important factor is the degree of
contamination in the operative fi eld. There is general consensus that
permanent prosthetic mesh materials should not be placed into heavily
contaminated or dirty fi elds. This scenario would most commonly be
encountered if strangulated intestinal contents had progressed to
perforation or if perforation had occurred during attempts to reduce the
strangulated contents (Fig. 8.6 ). Less commonly, signi fi cant spillage
could occur in the operative fi eld during resection and reanastamosis of
nonviable viscera. In either scenario, once the fi eld is classi fi ed as dirty,
a permanent prosthetic should not be used. Another way to think about
this scenario is that the hernia itself is no longer the patient’s primary
problem, and focus should be on treating the bowel and sepsis. The
hernia itself can be treated during a later staged repair. Options in this
setting include primary repair techniques, use of absorbable prosthetic
mesh, or placement of a biologic mesh. In all settings, the source of
contamination should be either controlled or well drained to optimize
outcomes. While use of prosthetic absorbable mesh essentially ensures
hernia recurrence, primary repairs and use of biologic mesh in fi elds with
controlled contamination may result in durable repair. Exact recurrence
rates will vary signi fi cantly base on individual patient scenarios. There is
Fig. 8.6. Gross contamination from small bowel perforation secondary to a
strangulated obturator hernia. Prosthetic mesh is best avoided in this situation.
99
8. Strangulated Inguinal Hernia
nothing worse than an infected synthetic in this scenario, and all efforts
should be made to prevent this from happening.
In the setting of clean-contaminated cases, or the potential for
contamination secondary to the presence of nonviable or marginally
viable tissue, there is less agreement on the use of permanent prosthetic
mesh for hernia repair. While many surgeons fear the potential for mesh
infection in this scenario, the majority of the available evidence supports
the safe use of prosthetic mesh material without increased rates of wound
or mesh infections. Nearly all types of permanent prosthetic have been
successfully used in this setting, including polyester, polypropylene, and
expanded polytetra fl uoroethylene (ePTFE). Reported strategies to
decrease the risks of potential mesh infection include placing the mesh in
a tissue plane remote from the area of potential contamination (i.e.,
preperitoneal) and decontamination of the plane with disinfectant solution
such as betadine or chlorhexidine prior to mesh placement. The bene fi t
of these strategies is unclear. Given the long-term bene fi ts of tension-free
prosthetic repairs, especially with respect to rates of recurrence, and the
available evidence to support its safe use, prosthetic repair should be the
option of choice for most surgeons repairing strangulated hernias in the
absence of gross contamination of the surgical fi eld.
A fi nal prosthetic-related factor to consider is the timing of prosthetic
placement. As discussed above, a “second-look” operative strategy may
be employed when the viability of reduced hernia contents is questionable
and resection is undesirable, not easily performed, or if the patient’s
physiologic status dictates the need for an abbreviated operation. If a
second-look operation is planned, it is probably best to defer placement
of prosthetic until the time of the last operation. The viability of the
contents and the presence or absence of contamination in the fi eld at the
time of open or laparoscopic reexploration will dictate how or if prosthetic
mesh should be used. Additionally, the use of systemic antibiotics to
treat infection in the interim between the initial and subsequent operations
may decrease the bacterial load in the operative fi eld and potentially
reduce mesh-related infectious complications.
Special Considerations: Obturator Hernia
Herniation of intra-abdominal contents through the obturator foramen
is an unusual but potentially life-threatening cause of a strangulated
groin hernia. These hernias present classically in older women, most
100
J.P. Pearl and E.M. Ritter
commonly on the right side, with up to 90% of patients presenting
initially with signs and symptoms of a partial or complete small bowel
obstruction. Given the subtle signs, the typical lack of a palpable hernia
bulge on physical exam and the comorbidities of the elderly affected
population, diagnosis of an incarcerated obturator hernia is often delayed
or not recognized until strangulation occurs. The mortality rate associated
with development of a strangulated obturator hernia has been reported as
high as 30%.
When an incarcerated or strangulated obturator hernia is suspected
based on history, physical exam, and/or imaging studies, a rapid
transperitoneal approach is warranted. This can be done by laparotomy
Fig. 8.7 Proposed algorithm for the surgical management of potentially strangu-
lated inguinal hernias.
101
8. Strangulated Inguinal Hernia
via either a low-midline or Pfannenstiel incision or, in hemodynamically
stable patients, via transperitoneal laparoscopic approach. With either
approach, visualization of the obturator foramen is facilitated with head-
down positioning of the patient on the operating table. Once identi fi ed,
the contents can typically be gently reduced, taking care to avoid bowel
perforation if at all possible. If reduction is dif fi cult, the obturator
foramen can be enlarged by incising the obturator membrane
inferomedially to avoid injury to the obturator neurovascular bundle.
Once reduced, the decision making follows exactly as outlined above
for all potentially strangulated groin hernias. If conditions allow for a
permanent prosthetic repair, it is easily done by entering the preperitoneal
space and obtaining wide coverage of the obturator defect with prosthetic
mesh. In contaminated operative fi elds, biologic mesh is probably the
best option as primary tissue repair at this location is usually not realistic.
Temporary exclusion of the obturator defect from the peritoneal cavity
with fat plugs, bladder, and bowel has been described but should be
considered only if a mesh alternative is not readily available. All potential
repairs can be performed via either laparotomy or a laparoscopic
approach. An algorithmic overview of the approach to potentially
strangulated hernias is presented in Fig. 8.7 .
Summary
Strangulated inguinal hernias occur with regularity and pose the risk of
serious morbidity and mortality. Prompt recognition and treatment is
imperative. The goals of operation for strangulated inguinal hernia are
reduction and inspection of hernia contents, resection of necrotic tissue,
and repair of the hernia defect. The operative approach can be either
conventional using the anterior or preperitoneal approach or laparoscopically
using a transabdominal, preperitoneal, or combined technique.
Suggested Reading
1. Bachman S, Ramshaw B. Prosthetic material in ventral hernia repair: how do I choose?
Surg Clin North Am. 2008;88:101–12.
2. Berliner SD, Burson LC, Wise L. The Henry operation for incarcerated and strangulated
femoral hernias. Arch Surg. 1992;127:314–6.
102
J.P. Pearl and E.M. Ritter
3. Campanelli G, Nicolosi FM, Pettinari D, Contessini Avesami E. Prosthetic repair,
intestinal resection, and potentially contaminated fi elds: safe and feasible? Hernia.
2004;8:190–2.
4. Malangoni MA, Condon RE. Preperitoneal repair of acute incarcerated and strangulated
hernias of the groin. Surg Gynecol Obstet. 1986;162:65–7.
5. Rebuffat C, Galli A, Scalambra MS, Balsamo F. Laparoscopic repair of strangulated
hernias. Surg Endosc. 2006;20:131–4.