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408
24 Hirschsprung’s Disease
resect the aganglionic segment and to pull down
a normoganglionic piece of colon without causing any harm to the pelvic organs, or their nerves,
and preserving intact the anal canal. This can be
done in a single, primary operation or with two or
even with three operations, depending on the specifi c circumstances of the patient, the surgeon’s
experience, and the surrounding environment.
The main goal can also be achieved using different techniques, laparoscopically or open. It is
fashionable among surgeons to talk about the
“gold standard” when referring to the best way to
treat a specifi c condition. It is also very common
for pediatric surgeons to compete trying to perform these operations earlier and earlier in life
and using the least invasive technique, with a
minimal length of stay in the hospital and minimal cost. Looking at our experience in dealing
with patients who came to our institution after a
failed attempted repair, or after suffering catastrophic preventable complications, lead us to
believe that it is not so important which treatment
modality was used. What is really important for
the patient is to be operated by a meticulous,
experienced surgeon, using the treatment modality with which he or she feels most comfortable
and with which the aforementioned goals can be
achieved.
Clearly, it is ideal to repair a defect as early as
possible, in the least invasive way, and in a single
operation, but far more important than that, to
avoid catastrophic, preventable complications
such as neurogenic bladder, fecal incontinence,
dehiscence, retraction, rectovaginal fi stula, and
rectourethral fi stulas.
24.10.1 The Authors’ Approach
If a baby is born nearby our institution or is
brought very early with symptoms consistent with
Hirschsprung’s disease, we perform a contrast
enema and a suction rectal biopsy. Once we establish the diagnosis, assuming it is a full-term baby
with no concerning associated defects and is clinically stable, we insert a central line (PICC line)
and keep the patient with nothing by mouth
receiving parenteral nutrition. We have learned
that these patients do not need a nasogastric tube
provided one keeps the colon decompressed. The
babies vomit when they have a distended colon
and have enterocolitis, but the decompression of
the colon stops the vomiting. A program of irrigations three times per day and intravenous metronidazole is started. The goal of the irrigations is to
avoid enterocolitis and to maintain the colon
decompressed and the abdomen fl at. Gradually,
over the period of a few days, we can see that
what used to be fetid liquid stool becomes less
and less so more clear and eventually becomes
bilious and odorless. Occasionally (rare in our
institution), one can see a baby suffering from
severe enterocolitis, endotoxemia, and shock
coming to the hospital. Under those circumstances, we understand that may be justifi ed to
open a colostomy to save the baby’s life. At least
in the environment where we work, this particular
situation occurs very rarely. Newborn babies
come to our hospital looking sick, yet, they
respond well to the management described and
can be operated primarily after a few days of medical management (irrigations and metronidazole).
At this point, with no evidence of enterocolitis, a nondistended colon, and the baby in good
condition, we perform a primary transanal repair.
Based on the fact that 85 % of the patients have
an aganglionic segment that extends only to the
rectosigmoid, we believe that it is necessary to
open the abdomen or to perform a laparoscopy in
approximately 15 % of the cases. Some surgeons
advocate the use of laparoscopy in all cases, to
take biopsies to determine the extent of the aganglionosis. We believe that it is not necessary to
follow that approach. Transanally, as we progress
in our dissection, we can take full-thickness biopsies every 5 cm until we reach the normoganglionic bowel. If the contrast study gives no clue as
to the location of the transition zone or if we are
suspicious of total colonic Hirschsprung’s, starting with laparoscopy and biopsies may be
appropriate.
We perform a full-thickness (like Swenson)
transanal (de la Torre) dissection. Based on a
large experience in the treatment of anorectal
malformations, we have learned to dissect the
rectum, keeping our plane of dissection as close
24.10 Surgical Treatment
409
as possible to the bowel wall without injuring any
nerves and/or pelvic organs. In other words, we
do not feel the need to do this dissection using an
endorectal, submucosal technique. As we gain
length in the dissection, we keep taking biopsies
every 5 cm, sending them to pathology. Once we
have reached the normal ganglionic bowel, we
still go 5 cm or more, proximally. If the normal
ganglionic bowel is very dilated, we continue
pulling down more colon. In other words, we try
to resect not only the aganglionic segment but
also as much of the dilated normal ganglionic
colon as possible. After the resection, a two-layer
anastomosis is done 2 cm above the pectinate
line. If, in the process of dissecting the rectum,
we fi nd that it is becoming technically more
demanding and diffi cult to continue the dissection because we already have passed the sigmoid
and reaching the descending colon becomes
extremely diffi cult, then we decide to go into the
abdomen either laparoscopically or opening the
abdomen to free the descending colon, the splenic
fl exure, or even the transverse colon.
The transanal approach is a very important signifi cant contribution in the therapy of
Hirschsprung’s disease. We believe that both Drs.
de la Torre and Langer should be commended for
this contribution. Yet, we have serious concerns
that this technique may 1 not be very reproducible.
In other words, when this technique is not done
correctly, serious damage may be provoked to the
sphincter mechanism and to the anal canal. We
have seen videos and photographs of transanal
operations presented in different meetings, showing images with rather aggressive, less-thanoptimal maneuvers that we believe may provoke
fecal incontinence. Because of that, we want to
emphasize what we consider the crucial steps in
the surgical technique of the transanal resection
of the rectosigmoid (see attached DVD).
We use a Lone Star
2
retractor to perform this
operation [ 102 , 103 ]. This retractor provides an
excellent exposure combined with minimal invasiveness. The baby is placed in the prone position
1
Lone Star Retractor System, CooperSurgical Inc.,
Trumbull, CT, USA.
2
See footnote 1.
with the pelvis elevated. We believe that there is
no need to operate on these babies in lithotomy
position, which is a reminiscent of adult surgical techniques. With the patient in prone position,
the surgeon works more comfortably in a horizontal fi eld without losing instruments and can
perform the dissection easier, and this position is
much easier on the assistant and the scrub nurse.
The eight hooks of the Lone Star retractor are
placed in a symmetric and radial way at the anal
margin in order to be able to see the pectinate
line (Fig. 24.5 ). Subsequently, all the hooks are
replaced deeper, taking the rectal wall above the
pectinate line (Fig. 24.6 ) so that it is hidden. At
that point, we know that what is exposed is only
rectal mucosa. We are now sure that the entire
anal canal, plus at least 1 cm of rectal mucosa, has
been circumferentially folded, retracted, and protected. What we see deep in our fi eld (Fig. 24.6 )
is only rectal mucosa. This way we can be very
accurate in measuring the distance between the
pectinate line and the beginning line of our resection. Many authors talk about initiating the resection 5 or 10 mm above the pectinate line. We
prefer to go 2 cm more proximal for the reasons
that we will explain when we talk about complications from these procedures. Multiple 5-0 or
6-0 silk circumferential stitches are placed taking the rectal mucosa (Fig. 24.7 ). These stitches
will provide uniform traction. We use a delicate
needle-tip cautery and make a full- thickness circumferential incision of the rectal wall, peripheral to the multiple silk stitches (Fig.
24.8 ). We
use the cautery in cutting mode when cutting and
coagulation mode to fulgurate specifi c vessels.
Peripheral to the full-thickness wall of the rectum, one fi nds a funnel-like skeletal muscle that
contracts every time we touch it with the cautery.
We should not violate that wall of skeletal muscle. If we go through that, we fi nd characteristic
ischiorectal fat that should alert us that we are too
far away from the correct plane and therefore at
risk of injuring other structures. The dissection of
the anterior rectal wall in male patients must be
performed very meticulously. It is perfectly valid
to go submucosally in this particular area to guarantee that we are not injuring the prostate and
the posterior urethra. Likewise in females, the
410
a b
Fig. 24.5 Eight hooks in place. ( a ) Diagram. ( b ) Intraoperative picture
24 Hirschsprung’s Disease
Fig. 24.6 Eight hooks placed deeper – only rectal
mucosa is exposed. The anal canal is protected (folded) by
the hooks of the retractor
posterior vaginal wall must be protected. If the
dissection is performed correctly, one fi nds that
dissecting the rectum in a full- thickness fashion
allows us to work in a bloodless fi eld only burning the extrinsic blood vessels of the rectum. This
represents a much less bloody fi eld than when
Fig. 24.7 Multiple silk stitches
using a submucosal dissection. When one is
performing this dissection in the right plane, the
dissection is performed most of the time outside
the level of the retractor. In other words, we keep
dissecting and pulling the rectum mostly outside
the anus; we try not having to work in a deep fi eld
24.10 Surgical Treatment
ab
411
Fig. 24.8 Circumferential incision, peripheral to the silk stitches. ( a ) Diagram. ( b ) Intraoperative picture
a
Fig. 24.9 Biopsies taken every 5 cm ( a ) 15 cm dissected, ( b ) 20 cm dissected
unless we are dealing with a reoperation with a
lot of fi brosis in the pelvis. Every 5 cm of length
that we gain, we take a full- thickness biopsy that
is sent to pathology (Fig. 24.9 ). Obviously, this
approach is safe when one is working in an environment with a pathologist who has experience
with frozen sections. In about 80 % of the cases,
we reach the normoganglionic bowel without the
need to open the abdomen or doing laparoscopy.
Yet, we go at least 5 cm above the site of the
biopsy that showed ganglion cells; we also resect
b
as much of the dilated normoganglionic bowel as
possible through the same transanal approach. A
two- layer anastomosis between the normoganglionic bowel and the rectum is performed, 2 cm
above the anal canal (Fig. 24.10 ). The fi rst layer
of the anastomosis takes the external or serosal
part of the colon and sutures it to the peripheral
tissues above the edge of the resection of the rectal mucosa. This fi rst layer of sutures is performed
before the resection of the colon. Figure 24.11
shows the resection of the colon. In the second
412
24 Hirschsprung’s Disease
Fig. 24.11 Resection of the colon
bowel. The dissection becomes more diffi cult and
risky because we are trying, through the anus, to
cauterize mesenteric intraperitoneal vessels that
may retract and bleed into the peritoneal cavity.
Under these circumstances, we go into the abdomen, either laparoscopically or by laparotomy.
This is easily done because we perform these
operations using what we call “total body preparation.” We use this type of preparation modality in all of our abdominoperineal procedures.
The reader can go to Chap.
7 to see the details
of a total body preparation. When necessary, the
Fig. 24.10 Diagram showing the deep layer of the
anastomosis
baby is turned to supine position and laparotomy
or the laparoscopic approach is performed. In
order to avoid the leak of CO 2 from the perito-
inner layer, more emphasis is placed in being
sure that the mucosal edges come together. This
suture is performed with 6-0 Vicryl (Fig.
24.12 ).
During the dissection, we assist ourselves with
the use of small pediatric malleable retractors
and a long, narrow Deaver retractor. During this
dissection, we work following the principle of
triangular exposure. We pull on the multiple silk
rectal stitches in one direction, use the suction
tube to improve the exposure, and 1 or 2 narrow
retractors are introduced in order to see exactly
what we are doing. We are very careful to not
excessively stretch the anal canal. We believe that
serious damage may be infl icted when the surgeon stretches the anal canal excessively in order
to have better exposure.
In about 20 % of patients, the dissection con-
tinues, but we cannot reach the normoganglionic
neal cavity, packing gauze can be used in the
anus. Laparoscopically, the descending colon is
detached from its normal (left gutter) attachments
as well as the splenic fl exure. This maneuver is
usually enough for the normoganglionic bowel
to reach the anus and to perform a successful
tension-free anastomosis. If there is not enough
length, we have to detach the hepatic fl exure to
gain extra colonic length. Sometimes the right
colon must be de-rotated for the hepatic fl exure
to reach the anus. Rarely, one is confronted with
the case of a total colonic aganglionosis which
should have been suspected preoperatively. This
will be discussed later.
If the decision is made to go into the abdomen
through a laparotomy, we prefer a midline incision. In dealing with colorectal problems, we
favor the midline abdominal incisions in order to
24.10 Surgical Treatment
ab
413
Fig. 24.12 Superfi cial layer of stitches (inner layer). ( a ) Diagram. ( b ) Operative picture
preserve both sides of the abdominal wall in the
event that the patient requires a stoma. Transverse
incisions invade the area of the stomas, and the
patients may end up with a stoma located too
close to an incision, which is a serious inconvenience, since it may interfere with the placement
of the stoma appliance.
At the end of the procedure, most of the time,
the patient stays without a protective colostomy,
provided we feel comfortable about the blood
supply of the pulled-through bowel as well as
the tension of the anastomosis. We believe that
strictures that occur at the anastomosis site are
due to poor surgical technique and frequently
ischemia of the bowel or excessive tension. If it
happens that the patient requires a laparotomy or
laparoscopy, the surgeon must be very careful in
observing the blood supply of the colon in order
to be sure that they ligate or cauterize the right
vessels to avoid ischemia of the distal bowel. The
anastomosis should not be done under tension.
When there is any question about the viability
of the bowel as well as the tension, a protective
colostomy is indicated.
Postoperatively, these patients recover remarkably well. They have no pain unless they had
a laparotomy or laparoscopy. They frequently
show signs of being hungry. We give broadspectrum antibiotics for 48 h. Metronidazole is
administered on a long-term basis, which we will
explain. Seven to ten days after the operation, we
start feeding the patients.
Many patients with Hirschsprung’s disease
are, or eventually become, lactose intolerant, and
414
ab
24 Hirschsprung’s Disease
Fig. 24.13 Characteristic image postoperative for Hirschsprung’s showing gas and liquid in the descending colon and
rectum. Indication for irrigation. ( a ) Before irrigation. ( b ) After irrigation
therefore, as early as possible, we suggest feeding them with a substitute for milk. In addition,
we have seen that the ingestion of milk tends to
produce more bowel gas and may show signs
of intolerance as well as increase the chance of
the patient to suffer from enterocolitis. We like
to feed the patients while still in the hospital, in
order to observe their reaction. We take an x-ray
fi lm to be sure that there is a normal colonic gas
pattern. We watch carefully for abdominal distension and irrigate the colon, through the anus,
if necessary.
Nowadays surgeons and institutions compete
to try to decrease the length of stay. Unfortunately,
sometimes this has been mainly motivated by
economic reasons rather than for the benefi t of
the patient. We have seen patients that have been
discharged very early from other institutions,
after a “successful” pull-through performed in
the newborn period, coming to our institution
suffering from severe enterocolitis.
The main concern for patients operated on for
Hirschsprung’s disease is the possibility of suffering from postoperative enterocolitis, which is
dangerous. Because of that, we keep the patients
in the hospital when we start feeding them. We
look for signs of abdominal distention. If the
baby throws up or becomes distended, we take
abdominal fi lms that usually show a characteristic image of a dilated colon with gas and liquid
stool (Fig.
24.13 ). In that case, we (the surgeons)
personally perform the fi rst colonic irrigation.
In a well-done anastomosis, the catheter should
go straight into the dilated bowel since there is
24.10 Surgical Treatment
415
no sigmoid. It is a “straight shot” that decompresses the baby’s colon. However, in general,
this should not be done by the nurses because the
surgeon must take the responsibility since he or
she is passing the catheter through a new, fresh
anastomosis. Metronidazole is administered
intravenously, and the irrigations are performed
three times a day which keeps the baby comfortable and stable. Eventually, the parents learn to
do this procedure. Once the baby is stable, not
vomiting and thriving, and the parents know how
to do the irrigations, we discharge the patient
home. The baby goes home taking metronidazole
by mouth and receiving three irrigations per day.
In addition, the mother is instructed to irrigate
more often if she feels that the baby needs it. We
have been very much infl uenced by Dale Johnson
et al. [ 104 ] concerning the prevention and early
management of postoperative enterocolitis, with
proactive rectal irrigations.
A month after surgery, the patients come to
the clinic and we take an abdominal x-ray fi lm. If
the colon is not distended, the baby is eating and
thriving, and there are no signs of enterocolitis,
we decrease the number of irrigations from 3 to 2
and decrease the amount of metronidazole by
50 %. A month later, the baby comes back again
and we do exactly the same. If the baby is doing
well, we keep reducing the number of irrigations
and the amount of metronidazole. Most babies
will do well. It may be necessary to administer
laxatives at the same time that the number of irrigations is reduced. Gradually, we expect the parents to report to us that the baby has spontaneous
bowel movements, in between irrigations, as well
as obtaining less liquid stool during the
irrigations. These are indications of the patient’s
colonic motility improvement. Occasionally, we
will fi nd babies that cannot tolerate the decrease
of rectal irrigations or lower dosages of metronidazole. Sometimes the treatment continues for
months. Under those circumstances, if a child is
“irrigation and metronidazole dependent,” we
consider a reoperation to resect more colon, even
knowing that it is a normoganglionic bowel.
Enterocolitis represents the greatest risk for
patients suffering from Hirschsprung’s disease
[
105 , 106 ]. It also represents the greatest research
challenge for the new generation of pediatric
surgeons. Several interesting papers have been
published shedding some light on the possible
etiology of the enterocolitis. Changes in the
mucin composition of the bowel, an important
mechanical and chemical factor of the mucosal
defense mechanism, have been advocated as a
possible cause [
107 , 108 ]. Also, cell activation
seems to play a role [ 109 ]. The role of bacterial
proliferation certainly contributes to the problem,
particularly Clostridium diffi cile [ 110 ].
We are aware of important predisposing factors [ 106 ] including Down syndrome, long-
segment aganglionosis, and infection. We believe,
like others [ 106 ], that fecal stasis is one of the
most important predisposing factors.
We do not know why babies suffer from enterocolitis. This is what we call a non- preventable and
non-predictable complication. After following
many patients, we have had the opportunity to
make an interesting observation. Some patients
come to us from centers where they claim they
have zero incidence of enterocolitis. Interestingly,
most of those patients suffer from fecal incontinence. We also know that patients with colostomies done in normoganglionic bowel do not have
enterocolitis. We postulate that an operation that
damages the sphincter mechanism producing
fecal incontinence ironically protects the patient
against the risk of enterocolitis. The stool fl ows
out with no obstruction and thus no stasis (like a
colostomy). One can ask a tongue-in-cheek question: what do we want: incontinence or enterocolitis? In our series, many patients (perhaps 70 %)
underwent the operation that we have already
described and did not suffer from enterocolitis.
We do not know why some do and some do not.
We believe that myectomies [
111 , 112 ] or
injections of botulinum toxin [ 113 , 114 ] into the
area of the sphincter play only a temporary role
in the treatment of this problem. These kinds of
treatments may produce a temporary improvement, because they decrease the effi ciency of the
sphincter mechanism. Repeated myectomies and/
or Botox injections eventually may avoid enterocolitis in a fecally incontinent patient! We prefer
to be proactive with irrigations and administration of metronidazole. The vast majorities of
416
ab
Pre-irrigation Post-irrigation
Fig. 24.14 Irrigation in cases of enterocolitis. ( a ) Contrast enema of a patient with enterocolitis. ( b ) Diagram showing
a colon, pre- and post irrigation
24 Hirschsprung’s Disease
patients eventually improve, do not require irrigations, and do not require metronidazole.
Figure 24.14a shows a contrast enema taken in
a patient with enterocolitis. Figure 24.14b shows
a diagram of a colon before and after irrigation.
We try to make the parents of our patients
paranoid about enterocolitis. A typical exceedingly sad event in pediatric surgery is when a
child gets sick at home with enterocolitis and dies
while being transported to a hospital. We tell the
parents about this and they learn to recognize the
fi rst symptoms of mild enterocolitis. We do not
wait until the patient has a full clinical picture of
enterocolitis to start irrigations; we rather make
the parents experts in the prophylactic use of
these irrigations. Often, this aggressive approach
with irrigations in response to abdominal distension keeps the patient from getting sick at all. We
look forward to hearing good news from scientists who are doing studies about the origin of
the problem of enterocolitis. Unfortunately, the
problem of enterocolitis post-Hirschsprung’s
operation is frequently unknown to many pediatricians or simply confused with gastroenteritis.
As a consequence, we have seen many babies
suffering from this condition, seen and treated by
pediatricians, simply receiving intravenous fl uids
and antibiotics, which may actually aggravate
the problem, particularly when the baby does
not receive the benefi t of the most important lifesaving therapeutic maneuver, which is the rectal
irrigation.
A small group of patients, after having a successful operation for Hirschsprung’s disease,
develop constipation without enterocolitis. We
believe that leaving a very dilated normoganglionic bowel, particularly in patients operated
using the Duhamel technique, may explain some
of the cases that suffer from constipation after an
operation for Hirschsprung’s disease.
The great majority of patients that had a successful operation for Hirschsprung’s disease have a characteristic defecation pattern consistent with the loss
of the rectosigmoid. Under normal circumstances,
the rectosigmoid represents our reservoir for stool
where a signifi cant absorption of water occurs, making solid stool. The colonic motility is more active
in the proximal (cecum, ascending) portion and less
active distally (descending colon and rectosigmoid).
In other words, the right colon moves faster than
24.10 Surgical Treatment
a
417
b
c
Fig. 24.15 Swenson operation ( a ) diagram showing lines of resection, ( b ) recto-sigmoid dissected and pulled through,
( c ) fi nished operation
the transverse; the transverse moves faster than the
descending, which moves faster than the rectosigmoid. Actually, the rectosigmoid remains quiet most
of the time. It just receives and stores the stool during 24 or 48 h. In a normal individual, after 24–48 h,
the rectosigmoid starts having peristaltic activity,
giving signs of an imminent massive contraction to
expel the stool, after which it remains quiet again
for another 24 h. This is extremely important and
valuable for us as human beings, because it allows
us to have a social life and not to need the use of a
toilet frequently. Resecting the rectosigmoid makes
sphincter) the patient must have in order to preserve
bowel control. When these operations are performed
in little babies and the proximal colon is connected to
the anal canal, the tendency of the baby after surgery
will be to have very frequent bowel movements that
will give him a diaper rash which is very diffi cult to
treat. We treat this condition by giving a constipating
diet, sometimes loperamide, and observing regularity in meals trying to decrease the number of bowel
movements. We assume that less frequent meals will
result in less bowel movements, which will make the
management of the diaper rash easier.
this function disappear. During a rectosigmoid resection (like the one performed for the treatment of
Hirschsprung’s disease), a more proximal portion of
the colon (usually descending) is anastomosed to the
upper portion of the anal canal. The colon that we
24.10.2 Other Surgical Techniques
for the Treatment
of Hirschsprung’s Disease
pull down does not behave like the rectosigmoid; in
other words, it does not act like a reservoir, but rather
tends to pass stool slowly but constantly, like a colostomy. The more proximal the colostomy, the more
constant the passage of stool and the more liquid the
consistency of the stool. Therefore, the more colon
we resect, the more effi cient anal canal (sensation and
The original operation of Swenson consisted
in the resection of the aganglionic portion of
the colon using an abdominoperineal approach
(Fig. 24.15 ). The aganglionic segment of the
bowel was mobilized transabdominally below
the peritoneal fl oor and a meticulous dissection