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438 Tirabassi et al.
Figure 7 Appendicostomy. A. Externalization of the appendix through the Y-
shaped incision. B. The immediate postoperative appearance of the appendicostomy
with a Foley catheter in place. C. A young teenager self-catheterizing. D. The low-
profile appearance of a healed appendicostomy.
Figure 8 Umbilical appendicostomy. This teenage boy has his appendicostomy
hidden within his umbilicus. A. Stoma catheterized for irrigation. B. With removal
of the button, the site is practically invisible.
Pediatric Intestinal Stomas 439
and the frequency of administration to achieve full colonic cleansing. Long
term, patients are maintained on a daily or every-other-day enema regimen.
Modifications are made to the content, amount, and frequency of enemas
based on individual results.
Malone’s follow-up in 1995 discussed 21 children, 12 of whom had
no further soilage and 3 who were without soilage 95% of the time [32].
The most successful children had meningomyelocele as the cause of incon-
tinence. The MACE is an effective method of colonic cleansing in patients
with fecal incontinence and intractable constipation. This procedure should
not necessarily replace standard medical therapy for these conditions, since
most children will respond to these therapies. Patients selected for the
MACE procedure must be carefully selected on the basis of age, underlying
disorder, commitment of the parents, and the patient’s desire to be indepen-
dent. Failure secondary to noncompliance is most often seen in children
less than 5 years of age [34]. This procedure has also been attempted on
the left colon (LACE procedure), but it was less successful [34a].
Developments over the last 11 years include the laparoscopic ap-
proach to the MACE procedure [35,36]. Results from these reports indicate
success rates comparable to those from the open procedure.
For patients who have had an appendectomy, a tube cecostomy can
be used. Various techniques have been described [37,38]. In 1996, Fuku-
naga placed a Bard gastrostomy button into the cecum with purse-string
sutures to invert the cecal wall. The button is exteriorized through a stab
incision, and the cecum is fixed to the anterior abdominal wall. Also in
1996, Shandling published a technique for a percutaneous tube cecostomy.
A rectal tube is inserted and air is pumped into the large bowel until the
cecum is distended. With the help of fluoroscopy, the position of the cecum
is marked on the patient’s abdomen. Under local anesthetic, cecal access is
obtained percutaneously using a retention suture needle. Contrast is injected
through the needle to confirm the position in the cecum. A guide wire is
passed through the needle, followed by dilators. Subsequently, a pigtail
catheter is placed with the cecum now secured to the anterior abdominal
wall via a second retention suture. Various low-profile devices such as the
trapdoor device and button gastrostomy can then replace the catheter [39]
(Fig. 9). Alternatively, a neoappendicostomy can be created using a vascu-
larized cecal flap tubularized over a feeding tube [40]. This is exteriorized
similarly to the natural appendicostomy. Plication of the cecum over the
base of the neoappendix is important, because this technique has a higher
incidence of leakage at the skin than the natural appendicostomy.
MACE surgery allows children a great deal of independence. They
can effectively and cleanly eliminate bowel incontinence. The child can
self-catheterize and administer the washout solution while sitting on the
toilet, and this entire process can be completed in less than an hour.
440 Tirabassi et al.
Figure 9 Percutaneous cecostomy. This is a minimally invasive alternative to a
surgical appendicostomy. With this procedure, a tube always remains in place.
Complications
The two most frequently found complications of the MACE procedure are
stoma breakdown and stenosis. In Malone’s initial 21 patients, stoma break-
down was reported in 5 [32], while 5 others required balloon dilatation for
stenosis. Other reported complications included wound infection, obstruc-
tion, pain with enema, and phosphate overdose. Curry et al. recommended
that all conservative measures of management—such as laxatives, diet
modification, suppositories, and enemas—be exhausted prior to undertak-
ing the MACE procedure [41]. They also offered the suggestion that sur-
gery at a young age (<5 years), and/or a diagnosis of a gastrointestinal
motility disorder may be bad prognostic indicators.
HIRSCHSPRUNG’S DISEASE
Background
Hirschsprung’s disease, or congenital aganglionic megacolon, is a disorder
characterized by abnormal motility of the intestine. The pathology begins
at the anus and reaches proximally to involve variable lengths of bowel.
The rectosigmoid segment is involved in approximately 80% of cases, and
another 5–10% will have involvement reaching to the small intestine
Pediatric Intestinal Stomas 441
[8,29]. The defect is due to an incomplete migration of neuroblasts distally
along the intestinal wall, resulting in absence of ganglion cells in Meiss-
ner’s submucosal and Auerbach’s myenteric plexuses. The affected seg-
ments lack the ability to appropriately relax and undergo peristalsis.
The incidence of Hirschsprung’s disease is about 1 per 5000, with a
male-to-female ratio of 4 to 1. Up to 90% of affected children present in
the neonatal period, while most of the remaining patients will present be-
fore the age of 2 years. A very small number of cases will not be detected
until adulthood [8]. The most common clinical presentation is failure to
pass meconium within 48 hr of birth. Approximately one-half of affected
neonates present with abdominal distention and bilious vomiting. Less fre-
quently, enterocolitis is the presenting symptom. A small proportion of
these babies may be detected during evaluation for chronic constipation
later in infancy, particularly if they were breast-fed newborns, who typi-
cally produce very soft stools.
The diagnosis in the newborn may first be suspected by distended
proximal bowel loops on plain abdominal radiographs as well as on un-
prepped barium enema (Fig. 10). The latter study will often reveal the tran-
sition zone between normal and aganglionic colon, with a diagnostic accu-
racy reported as high as 92% [42]. This boundary may not be obvious in
neonates. The diagnosis of Hirschsprung’s disease is based on pathological
verification of the absence of ganglion cells in the intestinal wall. A suction
rectal biopsy is obtained at the bedside or as an office procedure and can
provide diagnostic certainty in close to 100% of cases when examined by
an experienced pathologist. With this procedure, first described by Dobbins
[43] and Noblett [44], a small biopsy probe tip is inserted into the rectum
and directed posteriorly; suction is then applied with a simple hand pump.
When the biopsy device is engaged, a sample containing mucosa and sub-
mucosa is removed, ensuring an adequate amount and depth of tissue for
diagnosis.
Management
Hirschsprung’s cases most often present as partial or complete distal ob-
struction in children less than 2 years of age. Patients may also present with
explosive diarrhea, dehydration, and shock when signs are complicated by
enterocolitis. When Hirschsprung’s disease is clinically suspected, the diag-
nosis is proven with a suction rectal biopsy. The classic approach has been
surgical decompression with a colostomy. Some authors place a loop colos-
tomy in the proximal transverse colon [45], while others prefer the most
distal portion of normal intestine (i.e., transition zone) [8]. The transition
zone between dilated proximal ganglionic bowel and decompressed distal
aganglionic bowel may be seen intraoperatively, though the development
of this is infrequent in the newborn. This area of transition is no more than
442 Tirabassi et al.
Figure 10 Barium enema reveals dilated proximal colon with a tight rectal taper-
ing segment, corresponding to the transition zone.
a couple of centimeters in length. The location of the transition zone must
be confirmed by serial frozen sections of seromuscular biopsies (Fig. 11).
An ostomy placed within aganglionic bowel will not empty properly, lead-
ing to recurrent obstruction.
A loop colostomy, most commonly sigmoid, involves minimal disrup-
tion of the mesenteric vasculature, thus assuring adequate blood supply to
the anal anastomosis at the definitive reconstructive procedure. The creation
of the colostomy involves two layers of seromuscular sutures to the perito-
neum and the muscular fascia. Precise suturing of bowel wall to peritoneum
and fascia prevents parastomal hernia formation. Seromusculature suture
placement prevents intestinal fistulas. There is no need to suture the intesti-
nal wall to the skin. A red rubber catheter resting without tension on the
skin surface is passed through the mesentery at the elbow of the loop and
Pediatric Intestinal Stomas 443
Figure 11 Operative example of a rectosigmoid transition zone, with seromuscu-
lar biopsy sites. Sites A and B were negative for ganglion cells. Site C was positive
for ganglion cells.
is coiled to form a circle around the ostomy. This stabilizes the loop, fits
easily within the colostomy bag, and is removed after 2–3 weeks (Fig.
12). Alternatively, a bridge consisting of skin, anterior and posterior rectus
sheaths, and peritoneum may be brought together under the loop.
The intra-abdominal portions of the efferent and afferent limbs are
sutured together for a short length to provide protection against prolapse.
The fascial defect should be snug for this reason as well. In the past, the
colostomy was opened at least a day following surgery, allowing the inci-
sion to seal so as to prevent fecal contact and subsequent infection. Cur-
rently, the ostomy can be safely opened in the operating room by perform-
ing a longitudinal incision with electrocautery, extending more proximally
than distally. Prolonged placement of the rubber catheter may lead to effec-
tive defunctionalization of the distal intestine by directing the two limbs
away from one another. In the rare patient with disease reaching the right
colon, cecum, or small intestine, an ileostomy or jejunostomy may be nec-
essary. Multiple intraoperative seromuscular biopsies may be required to
determine the exact length of involved intestine.
444 Tirabassi et al.
Figure 12 An infant sigmoid colostomy, with the longitudinal opening and
looped red rubber catheter for stabilization.
After the ostomy has been created, the definitive pull-through repair
is planned in 3–12 months, depending on the degree of proximal bowel
dilatation, the patient’s age and size (typically 6–12 months and 20 lb.),
and the surgeon’s preference. The recent literature has recommended a de-
finitive repair at an earlier age rather than later, averaging approximately 3
months in one study [46]. The Swenson (Fig. 13), Soave (Fig. 14), and
Duhamel (Fig. 15) are the three popular pull-through techniques for colo-
anal anastomosis after resection of the involved segment. The use of a more
proximal decompressing ostomy, necessitating a third procedure for take-
down at a later date, has become less common.
Recently, several authors have described the use of a single-stage pro-
cedure without the creation of an ostomy [47–49]. These techniques have
compared favorably with their classic two-stage counterparts, though
Teitelbaum found a higher rate of postoperative enterocolitis in the single-
Pediatric Intestinal Stomas 445
Figure 13 The Swenson procedure. A. Colonic division with stapler above tran-
sition zone and eversion of rectal stump. B. Bringing the proximal colon into posi-
tion. C. Colorectal anastamosis. D. Final result after reduction.
staged group. This was attributed only to improved diagnosis and recogni-
tion of enterocolitis in recent years [50,51]. These procedures are reserved
for healthy infants without evidence of preoperative enterocolitis or severe
colonic dilatation. The full extent of disease must be known at the time of
repair to ensure appropriate bowel resection. One-stage laparoscopic ap-
proaches have also been developed, with good results and comparable com-
plication rates [52–55]. Finally, in another attempt to minimize the inva-
siveness, several groups have been performing the colorectal resection and
coloanal anastomosis using a one-stage, fully transanal approach [56–58].
Operating times and blood loss are significantly decreased as compared to
the traditional transperitoneal approach [59].
446 Tirabassi et al.
Figure 14 The Soave procedure. A. Colonic division above transition zone, with
dissection of rectal muscular cuff. B. Opening of everted distal rectum. C. Pull-
through of proximal colon, with anastamosis. D. Reduction of colon, with fixation
of muscular cuff to colon. E. Final result.
Pediatric Intestinal Stomas 447
Figure 15 The Duhamel procedure. A. Manual dissection of posterior rectum.
B. Enterotomy in distal recum, with postioning of proximal colon. C. End-to-side
colorectal anastamosis. D. Stapled division of rectum and colon to create pouch.
E. Final result.