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428 Tirabassi et al.
highest risk. Until resection with ostomy formation became the standard of
care, surgical management of NEC was not often successful. Sporadic cases
of necrotizing enterocolitis have been described in the literature since 1826
[1]. The first report of a neonate successfully treated surgically for NEC
was in 1943 [2], and NEC continues to be a frequent cause of morbidity
and mortality in the premature infant, occurring in 1–3 of every 1000 births
[3]. The average weight of infants with NEC is 1676 g [4].
The pathology in NEC is full-thickness coagulation (ischemic) necro-
sis and perforation of the bowel wall. The pathogenesis of NEC still re-
mains unclear, although many factors have been implicated. Indomethacin
treatment and cocaine exposure are particular pharmacological risk factors.
The incidence of NEC in infants who have never been fed is quite low.
Some authors have suggested that feeding may either cause or at least stim-
ulate the development of NEC in infants predisposed to this condition [5].
Molecular biological evidence has implicated a number of cytokines in
NEC. Both platelet activating factor (PAF) and tumor necrosis factor (TNF)
are found in high levels in the blood of neonates with NEC and are believed
to play major pathophysiological roles [6,7]. An unknown stimulus is be-
lieved to set off a chain of events leading to activation of inflammatory
factors, low-flow state, ischemia, bacterial infiltration, and necrosis. NEC
is not always a one-time event but has a recurrence rate of 4–6% [8].
Management
The three most common findings are abdominal distention (70–98%), blood
per rectum (79–86%), and high gastric residuals after feeding (>70%) [8].
Nonspecific signs include lethargy, temperature instability, and apnea [9].
Thrombocytopenia, neutropenia, metabolic acidosis, and coagulopathy por-
tend poor outcome [10]. Radiological findings in NEC can vary from a
nonspecific ileus pattern to the more specific signs including pneumatosis
intestinalis, portal vein gas, pneumoperitoneum, intraperitoneal fluid, and
persistently dilated bowel loops (Fig. 1).
Once recognized or diagnosed, NEC is treated with cessation of feeds,
gastric drainage, intravenous hydration, and broad-spectrum antibiotics.
When indicated, colloid, platelets, and fresh frozen plasma are given. More
than 50% of those patients can be managed nonoperatively [11]. Evidence
of pneumoperitoneum on left lateral decubitus or cross-table lateral abdom-
inal films is an absolute indication for surgery. Clinical deterioration, de-
clining platelet counts, and either increases or decreases in the white blood
cell count can be indicative of a turn for the worse. Metabolic acidosis and
a severely depressed platelet count may be indicators of ongoing intestinal
necrosis. Discoloration of the premature neonate’s thin abdominal wall is a
sign of peritonitis. A diagnostic peritoneal tap may be performed to prove
perforation.
Pediatric Intestinal Stomas 429
Figure 1 Pneumoperitoneum. Preoperative film of a premature neonate with per-
forated necrotizing enterocolitis. Free air is visible beneath both diaphragms. The
gas pattern overshadowing the liver is suspicious for pneumatosis.
Preoperative management includes correction of hypoxia and hypovo-
lemia and maintenance of the neonate’s body temperature. The operative
approach in these infants is a right supraumbilical transverse incision. This
incision avoids the possibility that the newborn’s large liver will obstruct
the exposure or become injured during the procedure. The entire gastroin-
testinal (GI) tract is inspected for evidence of perforation and necrosis. A
resection with primary anastomosis can rarely be done and is indicated only
in extremely localized disease, most commonly involving the terminal il-
430 Tirabassi et al.
eum. In 44% of cases, both the large and small intestines are involved. The
colon alone is involved in 26% of cases, while 30% of cases have disease
limited to the small intestine [8]. The process can be localized, segmental,
or diffuse, without clear demarcation. White or gray areas usually indicate
full-thickness necrosis. Lack of tone and peristalsis are ominous signs. Dis-
coloration secondary to intramucosal hemorrhage can make delineation of
the disease process more difficult.
The principles of operative management in NEC are resection of all
the gangrenous bowel and exteriorization of the questionably viable ends
to minimize the length of resection [12]. The length of residual bowel
should be measured on its antimesenteric border and recorded. NEC may
involve a short isolated segment (near 100% survival), multiple segments
(>50% survival), or panintestinal involvement (NEC totalis, <25% sur-
vival) [8]. Intraoperative decisions are directed at minimizing resection and
preserving, if possible, the ileocecal valve. Short gut syndrome may occur
in up to 23% of NEC survivors who have undergone a resection; thus every
attempt must be made to preserve bowel length [8]. Short gut syndrome is
a major risk in these patients if more than 40–50% of the small bowel has
been removed [13]. If the ileocecal valve can be salvaged and at least
20–30 cm of small bowel remains, total enteral feeds may eventually be
possible.
In infants with isolated disease, the approach is straightforward. Ne-
crotic and/or perforated intestine is resected and a proximal ostomy with a
distal mucous fistula is created. In selected cases, in order to save the
ileocecal valve, the distal bowel is oversewn if the line of demarcation is
close to the valve. A primary anastomosis is not created because the ends
of resection may have a tenuous blood supply and progress to necrosis.
Shock and peritonitis are contraindications to a delicate, time-consuming
anastomosis. The ostomies are exteriorized through the incision to accom-
modate the expected thickened and shortened mesentery and to prevent ad-
ditional compromise to the blood supply (Fig. 2). As opposed to placement
of adult stomas, ostomy placement in the laparotomy incision is very ac-
ceptable, since it is temporary and will facilitate dissection at the time of
ostomy closure. One centimeter of intestine is exteriorized and no attempt
to mature the ostomy is made. This may further diminish the blood supply
to the ostomy and is ultimately unnecessary. It also allows the visualization
of ongoing NEC insults. The ostomy serosa is fixed to the fascia using
interrupted sutures [8]. Single-layer fixation often results in early ostomy
prolapse. Therefore these ostomies are fixed in two layers, peritoneum and
fascia, with fine, nonabsorbable, braided polyester suture, carefully avoid-
ing blood vessels (Fig. 3). Securing the ostomy in one layer using full-
thickness bites through the entire abdominal wall has also been described
[15]. The pediatric surgical literature does not demonstrate statistically sig-
Pediatric Intestinal Stomas 431
Figure 2 Spontaneous stoma maturation. This neonate, about 2 weeks after ileal
resection for necrotizing enterocolitis, had both stomas brought through the inci-
sion. Both stomas have matured spontaneously.
nificant differences in the complication rate between these methods [15].
Once they are fixed, formal maturation of these ostomies is not needed but
will occur spontaneously in about 2 weeks.
In newborns with multisegmental disease, several options are avail-
able to minimize gut loss. Necrotic bowel is resected with the creation of
multiple ostomies (rarely more than four). Resections with primary anasto-
moses may be created if they are protected by a proximal jejunostomy. The
jejunostomy can be brought through a separate site below or above the
transverse incision. This approach has been described to maximize gut sal-
vage and minimize the number of ostomies [16,17]. As expected, proximal
432 Tirabassi et al.
Figure 3 Stoma fixation. The diseased end of bowel is exteriorized out 1 cm
above the skin. The bowel is anchored to both fascia and peritoneum. This stoma
will mature spontaneously.
jejunostomies generally are poorly tolerated by these newborns with inevi-
table nutritional, fluid, and electrolyte losses.
An alternative technique to improve bowel salvage and avoid ostomy
creation in these desperately ill babies is, as described in Vaughan’s 1996
report, to “clip and drop-back” [18]. Vaughan recommends removing the
obvious segments of necrotic bowel and then closing all of the ends with
titanium clips or staples. At a second-look operation in 48–72 hr, additional
resection is performed if required, and all segments are reconstructed to
establish continuity (Fig. 4).
In 1989 Moore first described his technique of “patch, drain, and
wait” [19], and he recently published a promising follow-up on his experi-
ence [20]. In Moore’s procedure, no resections are performed. The surgeon
identifies all perforations and closes them with a single layer of transverse
sutures (patch). Two Penrose drains exit from the lower quadrants of the
abdomen (drain). Following this, commitment is made to long-term total
parenteral nutrition, which can even be continued at home as the patient
improves (wait). The drains are not removed until all fecal drainage has
stopped. With spontaneous autoanastomoses in these infants, 70% of his
patients did not require re-exploration and fecal drainage stopped in less
than 2 months [20].
Pediatric Intestinal Stomas 433
Figure 4 Clip and drop back. This figure, adapted from Vaughan’s original pa-
per in 1996, depicts the use of surgical clips to isolate and resect necrotic pieces
of bowel.
434 Tirabassi et al.
Unfortunately, 19% of infants with NEC present with panintestinal
involvement, often with catastrophic consequences. The decision to forgo
treatment in these patients was made based on an expected fatality rate of
nearly 100% [8]. However, techniques with potential benefit have been
described in the literature. Creation of a high jejunostomy without resection
in a patient with massive necrosis of the small and large bowel has been
described by Martin and Firor [21,22]. Recently, Surgarman and Kiely re-
ported a 50% survival rate in a series of 113 patients utilizing a high jeju-
nostomy with re-exploration and reconstruction 6–8 weeks after the origi-
nal procedure [23].
In newborns described as extremely ill from intestinal necrosis and/or
perforation, the risks of laparotomy are feared to be prohibitive. Some have
been successfully treated with peritoneal drainage. Penrose drains are used
to create controlled enterocutaneous fistulas. The peritoneal cavity is
drained in the setting of the neonatal intensive care unit under local anesthe-
sia with a small Penrose drain. This technique was first described by Ein et
al. in 1977 [24]. Survival rates as high as 74% are reported [25]. Some
authors have reported survival rates higher than that of traditional laparot-
omy, most specifically in premature newborns weighing less than 1000 g
[25,26].
Stomal closure of the enterocutaneous fistula is typically performed
2–4 months after recovery. A high ostomy output often requires earlier
closure. Closures before 4–6 weeks are prohibitory due to residual inflam-
mation. A complete distal bowel contrast study is necessary before closure
to ensure that there is no distal obstruction or stenosis. Areas of stenosis
form in as many as 20% of cases as a result of the scarring from partial-
thickness necrosis [27,28]. If distal stenosis is present, a resection should
be done at the time of reconstruction.
Complications
Overall postoperative survival in NEC in the recent literature ranges be-
tween 65 and 81% [8]. These neonates are usually premature and quite
frail, predisposing them to serious complications. Horwitz et al., in a multi-
center review, reported a total complication rate 47%. The most frequent
complications were sepsis and stricture [11] (see Table 1).
Resections for NEC are done with an effort to conserve as much
bowel as possible, occasionally leaving ostomies with a tenuous blood sup-
ply. This predisposes the ostomies to ischemia and necrosis followed by
retraction (10–18%). Mucous fistulas re-epithelialized after necrosis with-
out adverse effect. However, if the functional ostomy necrosis extends deep
to the skin, revision is necessary to prevent stricture [29]. Ostomy closure
may be considered as opposed to revision, depending on time course and
clinical situation. Other common complications are peristomal hernia (10–
12%) and prolapse (<5%) [15]. Both of these complications may force re-
Pediatric Intestinal Stomas 435
Table 1 Complications in Necrotizing Enterocolitis
Sepsis 9%
Stricture 9%
Short gut 8.7%
Wound infection 5.9%
Stoma 4.7%
Bowel obstruction 3.5%
Renal failure 3.1%
Disseminated intravascular coagulation 3.1%
Intraabdominal abscess 2.3%
vision of early closure. An externally draining intestinal fistual from a
seromuscular suture penetrating the mucosa is not serious. However, a per-
foration draining into the peritoneal cavity obviously necessitates emer-
gency revision.
FECAL INCONTINENCE
Background
Fecal incontinence is a major problem for children who suffer congenital
anomalies such as spina bifida, Hirschsprung’s disease, imperforate anus,
or trauma and tumors resulting in spinal cord damage. Chronic constipation
is another process that affects many children. Patients and their parents
must learn to cope with these most unpleasant situations. In helping these
families, the ultimate goal is to maximize the patient’s independence, bowel
predictability, and cleanliness. Traditional measures to handle fecal inconti-
nence and constipation include dietary regimens, laxatives, digital disim-
pactions, and enemas. Since these patients may be insensitive to normal
colonic peristaltic flow, the most effective way to manage incontinence is
regularly scheduled colonic emptying.
Management
In 1987, Shandling and Gilmour introduced the enema continence catheter
(ECC) [30]. This specially designed catheter allows for the administration
of an enema without an immediate return. The catheter is placed in the
rectum and a balloon is inflated. The enema is secured in place with the
baffle secured against the anal skin, thus preventing leaking of enema con-
tents prior to removal of the catheter.
Based on Shandling and Gilmour’s report, Malone described a new
operative technique using antegrade colonic washouts to empty the colon—
the Malone antegrade continence enema (MACE) (Fig. 5). In Malone’s
436 Tirabassi et al.
Figure 5 Antegrade continence enema. While the child sits on the toilet, a red
rubber catheter is inserted into the appendicostomy and the colonic washout solu-
tion is instilled by gravity. An older child can do this without assistance, usually
within an hour.
initial report in 1990, he described a procedure whereby the appendix is
detached, reversed, and reimplanted into the cecum [31].
Subsequently that particular appendiceal approach was abandoned
[32]. Currently, the cecum is fixed to the anterior abdominal wall and the
closed end of the appendix is brought though the right-lower-quadrant ante-
rior abdominal wall (Fig. 6). A horizontal Y-shaped skin incision is made
in the right lower quadrant, leaving a triangular skin flap. The appendix is
opened along its antimesenteric wall for a distance comparable to the length
of the triangular skin flap. The tip of the triangular skin flap is then sutured
with absorbable suture to the apex of the antimesenteric slit and continued
circumferentially so the flap resembles a gutter. This buries the appendiceal
mucosa. The skin and subcutaneous tissue is then closed separately leaving
Pediatric Intestinal Stomas 437
Figure 6 Appendicostomy anatomy. The skin flaps both protect the appendiceal
mucosa and create a continent valve through which there is rarely soilage.
a Y shaped suture line with the mucosa of the appendix protected (Fig. 7).
An indwelling 8, 10, or 12F Foley catheter stents the appendicostomy for
2–4 weeks. The ostomy then provides a continent stoma through which
anterograde colonic washouts can be administered, thus preventing soilage.
The site is eventually managed with little or no dressing.
The stoma can be placed in the crease of the umbilicus for conceal-
ment to improve patient self-esteem (Fig. 8). Patient satisfaction with this
procedure exceeds 90%. Since a skin flap is not created with this modifica-
tion, plication of the cecum over the base of the appendix is necessary to
prevent leakage. With plication of the cecum, as many as 85% of patients
will have no leakage from their stoma and thus no need for a dressing [33].
Patients are started on postoperative day 1 with a daily regimen of
saline enemas, 50 mL twice daily, which is increased to 100 mL per year
of age by 1 week postoperatively. A period of time is then required to
determine the appropriate volume of enema; the solution administered
which includes tap water, normal saline, phosphate solution, or Go-lytely;