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444 E. F. Foley
Table 42.1 Factors implicated as risk factors for ostomy ischemia, retraction, and stenosis
Ostomytype
Ileostomy vs. colostomy
Transverse vs. left-sided colostomy
Loop vs. end ostomy
Emergency surgery
Patient factors
Obesity
Diabetes
Table 42.2 Operative considerations to reduce ostomy tension and ischemia
Full mobilization to the bowel and mesentery to the midline
Lateral attachments
Posterior attachments
Flexures
Omentum
Divide mesentery central to the marginal vessels
Consider upper abdominal ostomy placement if patient obese
Consider more proximal diversion
Transverse colon
Ileum
Convert loop to end or “end loop” ostomy
patients is short, and its fat content tends to make
it less elastic, making it more difficult to reach
the skin surface for the creation of an ostomy
without tension. Second, the abdominal wall in
obese patients is much thicker, contributing to
the challenge of creating a tension-free ostomy.
A loop ostomy may be more difficult than an end
ostomy to bring to the surface without tension as
the mesenteric vessels tend to be the major tether
limiting the reach of the ostomy, and these are
less commonly divided and freed with a loop
ostomy than with an end [7]. Certain underlying
patient characteristics may also contribute to the
likelihood of these complications, including the
patients’ age, underlying vascular health, smoking, and diabetes. Furthermore, data suggest an
increase in stoma ischemia and retraction with
emergency vs. elective procedures [10, 11]. Finally, an underlying diagnosis of Crohn’s disease
may lead to an increased rate of long-term retraction and stenosis due to the presence of recurrent
disease at the ostomy [9, 12].
Prevention
Efforts to reduce the incidence of stoma ischemia, retraction, and stricture are primarily focused on attempts to technically mitigate tension
and ischemia at the intestinal cutaneous anastomosis. A number of techniques may be helpful
and are listed in Table 42.2, but several deserve
some comment. First, it is critical to recognize
that the creation of a healthy stoma is crucial to
the success of the operation and at times can be
very challenging. As such, it demands the same
degree of attention, time, and effort as the other
important components of a gastrointestinal operation. Unfortunately, this essential understanding can be commonly lost, particularly at the end
of a complex and difficult operation where there
is an “emotional letdown” once a challenging resection is complete. A number of specific technical steps may require consideration to create a
healthy ostomy, particularly in difficult circum-
44542 Stoma Retraction/Ischemia/Stenosis
stances, and each of these may take some time
and careful thought. The overall technical goal is
to be able to reach a well-vascularized piece of
intestine to the skin surface without tension. To
do so, the bowel should first be fully mobilized
and rotated on its mesentery to the midline. For
the left colon, this may involve fully dividing
the lateral attachments (White line of Toldt), in
some cases fully mobilizing the splenic flexure
and the posterior mesenteric attachments to the
retroperitoneum. For the terminal ileum, this may
involve fully freeing the entire distal small bowel
mesentery off of the retroperitoneum to the level
of the duodenum. Upon completion of these maneuvers, the bowel should not be tethered by anything other than its mesentery. It should be kept
in mind that full mobilization and freeing the associated mesentery off the retroperitoneum can
often add substantial mobility to the intestine and
be all that is required. In many cases, this mobilization alone is sufficient to be able to bring the
bowel to the skin without tension and is ideal because significant mesenteric blood flow had not
been divided. If the bowel is still not adequately
mobilized at this point, it will be tethered by its
mesenteric blood supply alone, and decisions
regarding mesenteric division will need to be
made. Careful identification of the major feeding vessels as well as the marginal, pericolic vessels should be made prior to any division. If the
mesentery requires division, this division should
be done close to the root of the mesentery, central to the marginal or pericolic vessels that will
ultimately be the source of the blood supply to
the stoma. Mesenteric diversion in the periphery
close to the bowel wall will sacrifice the marginal
vessels’ perfusion of the bowel leading to ischemia. If these mobilization measures are still inadequate, consideration of the use of a transverse
colostomy or terminal ileostomy might be appropriate, as these structures tend to have longer,
more mobile mesenteries. Furthermore, positioning the ostomy aperture in the upper abdomen
may be helpful, as the abdominal wall of even
very obese patients is usually much thinner in the
upper rather than mid- or lower abdomen. Finally, as noted previously, if there is undue tension
on a loop ostomy, consideration of converting it
to an end ostomy with some mesenteric division
may be of benefit. Additional mobility may also
be achieved by conversion of the loop ostomy to
an “end loop” as described by Hebert [13], which
creates the ostomy aperture on the antimesenteric
side of the bowel, rather the end, which is less
tethered by the mesenteric vessels. Table 42.2
highlights the technical considerations and the
order in which I think about them when creating
an ostomy under difficult circumstances.
Recognition/Assessment/Severity/ Therapy
When concern about stoma ischemia and retraction arises in the early postoperative period, the
first question that needs to be considered is the
possibility of full thickness intestinal ischemia
proximal to the fascia. A glass test tube may be
gently inserted into the stoma aperture and often
is quite helpful in differentiating superficial mucosal sloughing from full thickness ischemia involving bowel deep to the fascia. Additionally,
progressive peristomal inflammation or signs
of systemic sepsis may indicate full thickness
stomal necrosis. If full thickness necrosis to the
fascia is suspected, the patient requires urgent
reoperation with laparotomy and recreation of
the ostomy to prevent intraabdominal intestinal
perforation and sepsis. Ostomy revision should
be done with the technical considerations discussed in the “Prevention” section in mind. If
the ischemia is more superficial or distal to the
fascia, usually expectant management is warranted, although the more severe the ischemia or
retraction, the more likely the need for eventual
elective ostomy revision. Occasionally, in the
absence of full-thickness ischemia proximal to
the fascia, a decision for early revision is made
with the goal of reducing the likelihood of future
stenosis requiring later revision. Factors which
may influence the decision to return for early ostomy revision under these circumstances include
the clinical state of the patient and the difficulty
of the initial stoma creation. Furthermore, if the
stoma is temporary, expectant management with
acceptance of temporary poor ostomy function
446 E. F. Foley
that will resolve with ostomy closure may be a
reasonable alternative to early reoperation. In
general, in the absence of deep full-thickness
ischemia mandating urgent reoperation, nonoperative, expectant management is usually undertaken in the immediate postoperative period.
Perioperative ischemia or tension not severe
enough to require urgent early reoperation may
result in chronic problems with stoma stenosis
or retraction. Initial non-operative interventions
may be tried. Bowel slowing and thickening
medications and the use of convex pouching may
improve minor-to-moderate pouching difficulties
related to retraction. Some authors have advocated the use of catheterization for stenotic colostomies as a mean of controlling partial obstruction
or pouching difficulties [14]. Serial dilations of
strictured stomas has been suggested, but the literature is quite mixed on the long-term effectiveness of dilation, and many authors do not advocate it [14,15]. I personally have not found this
to be effective for most patients with strictured
stomas.
The indications for elective surgical repair of
these difficulties essentially revolve around the
need for symptomatic relief of associated partial
intestinal obstruction with stenosis and difficult
pouching with retraction. Operations considered
for stoma stenosis may be categorized into local,
peristomal revisions and in-depth, transabdominal revisions. The selection of approach is based
on the degree of pathology. If the stricture is quite
superficial, involving the very distal end of the
bowel and the mucocutaneous junction only,
local repair may be adequate. Strictures that are
longer and extend more proximally in the bowel
will often require the more extensive transabdominal approach [1,2, 14, 15]. Categorizing
the depth of pathology can usually be done by
physical exam in the office. If there is healthy,
soft bowel just inside a superficial stricture, I will
often attempt a local repair. Many different techniques have been described for local stoma stricture revision, from simply excising the stricture
with advancement of the bowel and recreation of
the mucocutaneous junction, to more complex
approaches involving local skin flap mobilization
and peristomal skin “plasties.” V-Y advancement
flaps, “W-plasties,” and “Z-plasties” have all
been described to surgically correct stomal stenosis [4, 14, 16]. There appears to be no clear cut
data favoring one approach over another, with the
length and extent of the stricture and surgeon experience being the important factors influencing
the choice of specific approach.
A stricture of longer than several centimeters
indicates a longer segment of intestinal ischemia,
and usually this problem requires a transabdominal approach, with intraabdominal mobilization
of additional non-ischemic intestine to allow a
vascularized piece of intestine to the skin level
without tension. The technical considerations for
this operation are analogous to those discussed in
the “Prevention” section.
The major indication for surgically repairing
stoma retraction is to improve difficult pouching
related to the retraction that cannot be managed
acceptably with conservative measures of bowel
content thickening, slowing, and advanced enterostomal therapy care. Some authors advocate
a first attempt at local repair, with circumferential peristomal dissection of the bowel from the
abdominal wall and recreation of the ostomy
aperture [15, 17]. I personally have found this
approach often unrewarding, especially for those
patients with anything other than a mild retraction, as it is often difficult to free up enough
bowel with a local dissection to relieve significant tension and retraction. Under most circumstances, I have found that significant retraction
will eventually require a transabdominal approach to further mobilize intraabdominal intestinal length to reach the skin without tension. If
a local repair is planned, I do agree with authors
suggesting preparing the patient for the possibility of a laparotomy if adequate mobilization cannot be achieved with local dissection alone [14].
Preoperatively, a decision about the suitability of
the stoma position on the abdominal wall should
be made. As previously stated, lower abdominal
wall ostomies often transverse thicker abdominal walls and may contribute to retraction and
pouching problems. Furthermore, the placement
of an ostomy in a skin fold may exacerbate the
pouching problems related to retraction. Careful
preoperative enterostomal therapy evaluation is
essential to optimizing ostomy positioning on the
abdominal wall, and this is particularly true for a
44742 Stoma Retraction/Ischemia/Stenosis
planned ostomy revision. In addition to consideration of stoma repositioning, the technical goal
of this operation is to more adequately mobilize
intraabdominal, non-ischemic bowel to allow for
its tension-free anastomosis to the abdominal
wall skin, again as specifically described in the
“Prevention” section.
Conclusions
The common complications of peristomal ischemia, retraction, and stenosis are clinical manifestations of differing degrees of the same pathologic entities of ischemia and tension. Specific
technical considerations can and should be made
at the time of ostomy creation to reduce their
incidence and the often substantial patient morbidity associated with them. Once present, the
specific clinical scenario dictates the timing and
nature of their surgical correction.
Five Keys Points in Diagnosing and Managing Stenosis, Retraction, and Ischemia in an Ostomy
1. Insertion of a test tube into the ostomy aperture may assist in differentiating superficial
and subfascial stoma ischemia.
2. Subfascial ischemia requires urgent reexploration to repair.
3. The duration of planned diversion is a major
factor in deciding when to reoperate on a superficially strictured or retracted stoma.
4. Most strictured stomas involving more than
simply the skin or distal 1–2 cm of bowel will
require a laparotomy and intraabdominal mobilization to repair.
5.
Superficial skin strictures may be surgically repaired with peristomal skin flap mobilization
.
Five Key Points on How to Avoid Tension and Ischemia in an Ostomy
1. Full bowel mobilization:
− mobilize the bowel and mesentery to the
midline;
− lateral attachments;
− posterior attachments;
− flexures; and
− omentum.
2. Divide mesentery central to the marginal vessels.
3. Consider upper abdominal ostomy placement
if patient obese.
4. Consider more proximal diversion:
− transverse colon and
− Ileum.
5. Convert loop to end or “end-loop” ostomy.
References
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3. Mealy K, O’Brion E, Donohue J, Tanner
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4. Shabbir J, Britton DC. Stoma
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9. Duchesne JC, Wang YZ, Weintraub SL, Boyle M,
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Hebert JC. A simple method for preventing retraction of
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itley G, Allan A. Use of w-plasty in
Incontinence After Lateral Internal Sphincterotomy/ Fistulotomy
Heather Rossi and David Rothenberger
43
Introduction
Incontinence is defined as the involuntary loss
of feces or intestinal gas through the anal canal.
Severity ranges from the occasional leakage of
stool or gas to the complete loss of bowel control. Normal continence is maintained by complex interaction of the anal sphincter muscles and
pelvic floor innervation. Extreme diarrhea and
other diseases can result in incontinence despite
an intact anatomic and neural pelvic floor but
most often, incontinence is due to disruption of
the normal anatomy and/or neurophysiology [1].
Such disruption may be due to the unintended sequelae of sphincterotomy and/or fistulotomy.
The anal sphincter is composed of the internal anal sphincter (IAS) and the external anal
sphincter (EAS). The IAS is a 0.3–0.5-cm thick
continuation of the circular smooth muscle layer
of the rectum and the EAS is 0.6–1.0-cm thick
continuation of the levator ani muscles. The
IAS is primarily involuntary, fatigue-resistant
slow-twitch smooth muscle, while the EAS is a
voluntary, striated muscle. The IAS contributes
70–85 % of the resting pressure and is therefore
D. Rothenberger ()
Department of Surgery, University of Minnesota Medical
School, Minneapolis, MN, USA
e-mail: rothe002@umn.edu
H. Rossi
Division of Colon and Rectal Surgery, Department
of Surgery, University of Minnesota Medical School,
Saint Paul, MN, USA
e-mail: hrossi@crsal.org
primarily responsible for maintaining anal continence at rest [2]. The anal endovascular cushions
of the anal mucosa may produce pressures up to
9 mmHg and contribute 10–20 % of anal resting
tone [3]. The IAS is also responsible for the sampling reflex of the rectum. Relaxation of the IAS
permits rectal contents to come in contact with
the anal mucosa. The sampling reflex allows for
the discrimination of flatus and stool. This discrimination results in the passage of flatus while
maintaining continence to stool [4]. The EAS is
primarily responsible for the squeeze pressure or
voluntary control of the passage of stool from the
anus. Damage to the IAS or endovascular cushions may lead to a decrease in the resting pressures and passive incontinence, seepage of stool,
or impaired sampling reflex. Damage to the EAS
may cause voluntary loss of control and/or urge
related defecatory dysfunction.
Lateral Internal Sphincterotomy
An anal fissure is a tear in the mucosa of the anal
canal distal to the dentate line and extending to
the anal verge. The majority of fissures are acute,
located in the midline posteriorly, have an equal
prevalence in men and women, not related to a
specific disease state, and resolve with conservative management within 6–8 weeks. A chronic
anal fissure (CAF) is generally defined as a tear
that has extended through the submucosa, to expose the IAS. It is often associated with a sentinel
perianal skin tag distally and/or a hypertrophied
T. M. Pawlik et al. (eds.), Gastrointestinal Surgery, DOI 10.1007/978-1-4939-2223-9_43,
© Springer Science+Business Media New York 2015
449
450 H. Rossi and D. Rothenberger
Fig. 43.1 Open
lateral sphincterotomy.
a Radial skin incision
distal to the dentate
line exposing the intersphincteric groove.
b Elevation and
division of the internal
sphincter. c Primary
wound closure. (With
permission from [67]
© Springer)
anal papilla proximally. Some authors also suggest that the definition of CAF should include
being present for at least 6 weeks [5–7]. Lateral
internal sphincterotomy (LIS) continues to be the
most effective first line surgical treatment for patients with CAF who fail medical management
[8, 9]. Hypertonia of the IAS is thought to be the
pathophysiology of CAF. Manometric and Doppler studies of patients with CAF have demonstrated persistent high pressures and decreased
perfusion of the IAS [10, 11]. Doppler studies
have demonstrated improved blood flow to the
anoderm following LIS and fissure healing rates
of 90–100 %. Up to 30 % or more of these patients
experience some sort of incontinence, most of it
temporary and most incontinence related to flatus
[10, 12, 13]. However, some studies have demon-
strated that the incidence of incontinence may increase with time and long-term incontinence rates
might be higher than reported [9, 14, 15].
Sphincterotomy for the treatment of CAF
was first described by Brodie in 1835 and was
popularized by Eisenhammer in 1951. The initial
description of the technique involved complete
division of the internal sphincter [16]. However,
the high incontinence rate associated with this
technique led to various tailored approaches including limiting division of the distal internal
sphincter to the length of the fissure [17–19].
A randomized prospective trial comparing traditional and tailored sphincterotomies was performed in 2005. Continence was significantly
worse in those patients whose sphincter was divided to the dentate line [20].
Several techniques for sphincterotomy have
been described. Classically, a posterior midline
internal sphincterotomy to divide the internal
sphincter in the bed of the posterior fissure was
the operative procedure of choice. Development
of a posterior keyhole deformity, postoperative
pain, and prolonged healing has been associated
with this procedure. Increased levels of postoperative incontinence when compared to LIS have
also been reported. For these reasons, posterior
sphincterotomy is rarely used today [21–24].
LIS involves partial, lateral division of the
IAS. Both an open and closed (subcutaneous)
technique has been described. The open technique involves either a vertical or radial incision
in the intersphincteric groove (Fig. 43.1). The internal sphincter is identified and divided under
direct vision. The closed technique involves advancing a small blade through the anoderm into
the intersphincteric groove with blind division of
the IAS (Fig. 43.2). Similar healing rates have
been reported following both techniques, but
some suggest the closed technique is associated
with a more rapid recovery [23–27].
Fig. 43.2 Closed
lateral internal sphincterotomy. a Location
of the intersphincteric
groove. b Insertion of
the knife blade in the
intersphincteric plane.
c Lateral to medial
division of the internal
anal sphincter (inset:
medial to lateral division of the muscle).
(With permission from
[67] © Springer)
45143 Incontinence After Lateral Internal Sphincterotomy/Fistulotomy
Healing rates for CAF following LIS have
been reported as high as 95 % [28–30]. Reported incontinence rates vary from 0 to 50 % [27,
30–34]. This wide variance had been attributed
to multiple factors including surgical technique
(open versus closed), length of LIS, type of anesthesia (local versus general), previous anorectal
surgery, obstetric history, and inadvertent injury
to EAS (Table 43.1) [9]. Perhaps the most important factor underlying the wide variation of
reported incontinence rates following sphincterotomy is methodology of assessing the outcomes. Common methodological deficiencies
include lack of clear definition of incontinence,
failure to include the number of patients operated
versus those surveyed, inadequate or poorly defined length of follow-up, use of nonstandardized
or nonvalidated questionnaires, and failure to
Table 43.1 Factors responsible for wide variance noted
in incontinence rates following LIS
Surgical technique (open versus closed)
Length of LIS
Type of anesthesia (local versus general)
Previous anorectal surgery
Obstetric history
Inadvertent injury to EAS
use nonbiased, objective examination of sphincter function. Of note, a recent Cochrane review
(2011) evaluating the operative procedures for
fissure-in-ano concluded that the combined analyses of open versus closed LIS show little difference between the two procedures in fissure
persistence and risk of incontinence [35]. However, in regard to short- and long-term follow-up,
452 H. Rossi and D. Rothenberger
Table 43.2 Risk factors for incontinence following LIS
Age over 40
Female gender
History of vaginal delivery
Anterior fissure
Synchronous anorectal procedure
Operative technique
Fistulotomy
The goal of surgical treatment for anal fistula is
eradication of the fistula tract without compromising sphincter function. Fistulas can be classified as “simple” or “complex.” “Simple” fistulas are of cryptoglandular infection, are usually
distal intersphincteric or distal transsphincteric
and can be treated by lay open fistulotomy with
Nyam et al. (1999) reported a 45 % incontinence
in the short-term outcome, decreasing to < 11 %
in long-term follow-up [33]. Lewis et al. (1988)
reported a 17 % incontinence rate. This was only
temporary in two-thirds of these patients [25].
The overall risk of incontinence in randomized
surgical trials is reported to be about 10 % and is
mostly incontinence to flatus [36].
A 2012 meta-analysis identified subsets of individuals more prone to continence disturbances
after sphincterotomy for fissure. These include
age over 40, female gender, history of vaginal
delivery, anterior fissure, addition of a synchronous anorectal procedure, and operative technique (Table 43.2) [15]. Preoperative anal manometry and endoanal ultrasonography should
be considered in those high-risk patients to help
delineate and define any possible preexisting
sphincter injury and associated sphincter weakness.
Murad-Regadas et al. (2013) conducted a prospective observational cohort study to determine
the proportion of the IAS that may be divided
during LIS in continent women without predisposing them to fecal incontinence [37]. 3D-endo
anal ultrasound was used to evaluate the extent
of the surgically divided portion of the IAS. Postoperative continence was objectively assessed
via the Cleveland Clinic Florida score. They
found that follow-up continence scores were sig-
reported success rates reported over 90 % [39].
Those “simple” fistulas that involve proximal
(high) intersphincteric or transsphincteric tracks
are more difficult to manage. Fistulotomy of such
proximal anal fistulas is associated with lower
healing rates and higher rates of incontinence.
“Complex” fistulas including those arising from
noncryptoglandular origin such as those associated with perianal Crohn’s disease, those persisting
or recurring despite prior surgical interventions,
and those of cryptoglandular origin that crosses
> 30–50 % of the external sphincter, are anterior
in a female, are associated with multiple tracts,
develop in an individual with some degree of existing fecal incontinence, or occur in previously
irradiated tissue (Table 43.3) [40]. Reported rates
of incontinence after surgery for such “complex”
anal fistulas vary from 0 to 25 % for flatus, up
to 26 % for major fecal leakage, and as high as
63 % for minor and/or passive incontinence [41].
Female gender, type of surgery, prior fistula surgery, posterior internal opening, and horizontal
extension have been variables associated with
postoperative incontinence. Reported fistula recurrence rates range from 0 to 30 % and have
been associated with a horseshoe tract, missed
tracts, failure to identify the internal opening,
prior surgery, and surgeon experience [41]. For
distal (low) fistulas, it is generally accepted that
the risk of incontinence is minimal and fistulotonificantly correlated with the extent of sphincter
division. Continence was significantly better in
those women whose sphincter division was less
than 25 % versus those women with division of
25 % or more. Garcia-Aguilar et al. (1998) found
that the IAS defects were wider in patients with
incontinence than in those who were continent
but this was not significant [38].
Table 43.3 Complex versus simple fistula
Noncryptoglandular origin
Cross > 30–50 % of external sphincter
Anterior in females
Associated with multiple tracts
Develop in an individual with continence disturbances
Occur in previously irradiated tissue
Fig. 43.3 Transsphincteric fistula with hydrogen peroxide in the tract. (Courtesy of Dr. Amy Thorsen)
45343 Incontinence After Lateral Internal Sphincterotomy/Fistulotomy
my is advocated if less than one-third of the external sphincter is crossed by the fistula [42–44].
Several surgical techniques have been described to address high or complex anal fistula.
The anatomy of these tracts can be defined in the
operating room with fistula probes and/or with
the aid of dyes or hydrogen peroxide. Alternatively, radiographic evaluation with either endoanal ultrasonography (with or without hydrogen peroxide injection) (Fig. 43.3) or magnetic
resonance imaging (MRI) (Fig. 43.4) may prove
helpful to identify the fistula and help quantify
the amount of IAS and EAS involved by the tract
and at potential risk for division [45–47].
Both draining and cutting setons may be used
for high or complex fistulas. After defining the
fistula tract with a probe, the surgeon may elect
to use a combination of a seton placed through
the tract and a partial sphincterotomy. A draining seton is used to assure complete resolution
of associated abscesses and to induce fibrosis
along the tract. When the inflammatory process
has resolved, the seton may either be removed in
hope that the fistula will go on to heal without
further division of muscle or it can be removed
and additional fistulotomy performed. Sometimes the draining seton is converted to a cutting
seton or in the absence of significant associated
abscess and inflammation, a cutting seton may be
used instead of a draining seton in the first procedure. The cutting seton is gradually tightened
Fig. 43.4 Horseshoe fistula identified on MRI. (Courtesy
of Dr. Sid Walker)
to slowly divide the remaining involved muscle
in the fistula tract. This theoretically allows scar
to form as the seton is slowly “walked through
the sphincter,” thus keeping the sphincter muscle
intact and avoiding a wide gap as is noted when
muscle is divided in one procedure.
Eradication of the fistula is reported to be
60–78 % with recurrence rates between 2 and
9 %. Although the cutting seton at one time was
thought to preserve continence in comparison
with direct division, reports have not confirmed