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128 Pearl et al.
rectus muscle at the ostomy site to allow for complete eversion of the
stoma. The greater omentum should be dissected from the colon around the
point of partial transection to facilitate maturation. As with a loop ileos-
tomy, a rod is placed through the mesentery of the colon to support the
loop on the surface of the abdomen; the rod is usually left in place for 7–10
days. Separate fascioseromuscular tacking sutures are not only unnecessary
but may, in fact, interfere with the closure. The loop is opened in a trans-
verse fashion for about two-thirds of its circumference. The full thickness
of the bowel wall of each limb is everted and sutured to the surrounding
skin with interrupted absorbable sutures, so that the bowel wall is nearly
flush with the abdominal wall, and a colostomy management system is ap-
plied. Again, if appropriate, the ostomy support rod may be avoided.
End-Loop Stomas
The rodless end-loop stoma described by Prasad et al. (see Suggested Read-
ings) is a simple modification of a loop stoma with several important ad-
vantages. First, it is technically easy to construct. Second, it does not re-
quire a supporting rod or a separate opening in the abdominal wall for a
mucous fistula. These advantages facilitate stoma care because a single cir-
cular ostomy device readily covers the openings of both the proximal and
distal limbs without the interference of a rod. End-loop stomas are also
easy to close. A formal laparotomy is not required because of the proximity
of the two limbs. This fact is a distinct advantage of the end-loop ileocolos-
tomy over the more traditional approach of dealing with the divided ends
of the ileum and the transverse colon in cases where immediate ileocolic
anastomosis is inadvisable after right hemicolectomy (e.g., right-lower-
quadrant end ileostomy and left-upper-quadrant end transverse mucous fis-
tula after penetrating trauma to the right colon). The technical details of the
three variations of end-loop stomas are presented in Figs. 4 through 6.
POSTOPERATIVE CARE AND CLOSURE
A sterile transparent ostomy pouch should be applied in the operating room
so that the stoma can be inspected regularly in the postoperative period. If
the margin of the stoma becomes dusky or edematous during the first 24 to
72 hr, it is usually not necessary to revise the stoma. However, a completely
dark or black stoma must be evaluated for extension of the necrosis to
beneath the fascia, in which case the stoma should be reconstructed on an
emergency basis.
As a general guideline, closure of a diverting stoma should not be
performed within 8 weeks of its formation. In addition, it is important to
make sure that no distal obstruction or evidence of active inflammatory
Diverting Stomas 129
Figure 4 End-loop colostomy. A. After abdominal exploration through a midline
incision, a circle of skin is excised and an opening is made through the rectus
muscle as for an end colostomy. B. The colon is divided with a linear-cutting
stapler at a point where both the proximal and the distal limbs of the colon can be
brought through the opening in the abdominal wall without tension. C. The entire
divided edge of the proximal limb and the antimesenteric corner of the distal limb
are gently drawn through the opening in the abdominal wall. After the abdomen
has been closed, the staple line of proximal limb is excised completely and only
the antimesenteric corner of the distal staple line is removed. D. The proximal limb
is matured flush with the skin by suturing full-thickness skin to full-thickness colon
with absorbably sutures. Two transition sutures are placed to help mature the mu-
cus fistula, which has the appearance of a “ministoma.” E. Sagittal view of the
completed end-loop colostomy. Note the position of the distal staple line in the
subcutaneous tissue. (After Pearl.) (From Ref. 17.)
disease that might compromise the anastomosis is present. Endoscopic ex-
amination or a high-quality contrast study of the distal limb is usually per-
formed to assess the integrity of the suture or staple line. A standard me-
chanical and antibiotic bowel preparation is used and may be supplemented
with one to two perioperative doses of a cephalosporin administered paren-
terally. There is evidence that there is no difference between sutured or
stapled closure of an ostomy [5]. Furthermore, some surgeons use laparos-
copic techniques for closure of diverting stomas.
An elliptical incision is made adjacent to the mucocutaneous junction
of a loop or end-loop stoma and is continued downward along the serosal
130 Pearl et al.
Figure 4 Continued.2
surfaces of both ends or the bowel until they are fully mobilized (Fig. 7).
The skin and the fibrous tissue adherent to the edges of the bowel are
excised and a hand-sewn anastomosis is formed between the two ends.
With many of the end-loop stomas, a side-to-side stapled anastomosis can
be accomplished readily. The reconnected bowel is then returned into the
peritoneal cavity and the rectus sheath is closed. The skin may be left open
to heal by secondary intention or, in selected cased, may be approximated
loosely. The use of intraperitoneal drains is not recommended.
Diverting Stomas 131
Figure 5 End-loop ileocolostomy. A. Severe trauma to the right side of the co-
lon, necessitating right hemiocolectomy. The distal ileum and the right transverse
colon have been divided with the linear-cutting stapler. B. Both limbs of the end-
loop ileocolostomy are brought out through the rectus muscle in the right upper
quadrant. C. The end of the distal ileum and the antimesenteric corner of the right
transverse colon are gently drawn through the circular opening in the abdominal
wall. The mesenteric defect created after removal of the right colon must be closed.
The ileostomy is matured in the everted fashion. D. Sagittal view of the completed
end-loop ileocolostomy. E. Two transition sutures are placed to help mature the
mucous fistula. (After Pearl.) (From Ref. 17.)
132 Pearl et al.
Figure 5 Continued.
COMPLICATIONS
The formation and closure of diverting stomas is associated with an appre-
ciable morbidity. The most important preventive measure is recognizing the
magnitude of the potential problems that can develop and, with these in
mind, paying strict attention to technical detail. When a complication does
arise, it should be recognized promptly and dealt with in an appropriate
manner.
Metabolic complications are more common with the formation of a
loop ileostomy than with a loop colostomy. The volume of fluid lost from
an established ileostomy averages 500 mL/day, including about 60 mEq of
sodium. In cases of ileostomy dysfunction, significant sodium and water
Diverting Stomas 133
Figure 6 End-loop ileostomy. A. The ileostomy incision is placed in the right
lower quadrant overlying the rectus muscle. B. The ileum is divided with the linear-
cutting stapler at a point where the proximal and distal limbs can be drawn through
the abdominal wall without tension. C. The divided end of the proximal ileum and
the antimesenteric corner of the distal ileum are gently drawn through the opening
in the rectus muscle. The mesenteric defect is closed. D. Sagittal view of the com-
pleted end-loop ileostomy. E. Two transition sutures are placed to help mature the
distal “ministoma.” (After Pearl.) (From Ref. 17.)
134 Pearl et al.
Figure 6 Continued.
losses can occur and can lead to rapid dehydration. In one study, 23 of 117
patients with loop ileostomies (20%) required hospital admission because
of dysfunction. Another metabolic complication of ileostomy is the forma-
tion of urinary calculi. This complication occurs in 3–13% of patients and
is related to chronic dehydration and sodium depletion. To avoid dehydra-
tion, patients with an ileostomy should be encouraged to drink several
glasses of water daily.
Cholelithiasis occurs in up to 30% of patients with ileostomies. Gall-
stones form in these individuals because resection or inflammation of the
terminal ileum interrupts the enterohepatic circulation, resulting in malab-
Diverting Stomas 135
Figure 7 Closure of a diverting stoma. A. An elliptical skin incision is made
around both limbs of the ileum. B. After both limbs have been completely mobi-
lized, the ends of the ileum and surrounding scar tissue are excised and a side-to-
side stapled anastomosis is made. Care must be taken to avoid injury to the ileal
mesentery. C. Closure of the loop is facilitated with a linear stapler. (After Pearl.)
(From Ref. 17.)
136 Pearl et al.
sorption or depletion of bile acids—conditions that favor the precipitation
of cholesterol stones.
One of the most common problems associated with the formation of
a loop ileostomy is local irritation and breakdown of peristomal skin, which
occurs in about 15% of patients. This complication usually results from
improper location of the stoma or other technical problems associated with
stoma construction. In a prospective study comparing complications of loop
ileostomy with those of loop transverse colostomy, the incidence of skin
irritation was greater (30 vs. 13%) in those patients with loop colostomies
[6]. The authors explain that, although the median daily effluent of the
ileostomy group was nearly twice that of the colostomy group (438 vs. 265
mL), the spout of the ileostomy made collection of the effluent more effi-
cient, thus minimizing leakage around the stoma.
Small bowel obstruction occurs in approximately 10% of patients with
loop ileostomies yet is noted much less frequently with loop colostomies.
This situation is probably so because the intact transverse or sigmoid meso-
colon walls off the small bowel and prevents it from twisting. In contrast,
a segment of small intestine can rotate around the base of a loop ileostomy
at the point of fixation to the anterior abdominal wall, resulting in obstruc-
tion.
Retraction of loop stomas has been reported in 4–13% of patients.
Such retraction usually results from inadequate mobilization of the mesen-
tery of the bowel to be exteriorized at the time of stoma creation. The
special significance of retraction in loop stomas is that it has been consid-
ered a cause of incomplete fecal diversion. The use of fascioseromuscular
“tacking” sutures will not alleviate retraction of a loop stoma if the mesen-
tery is under tension. In obese individuals, it may be necessary to make one
or more “relaxing” incisions in the peritoneum of the bowel mesentery in
order to gain adequate length to properly exteriorize a loop stoma.
Prolapse of a loop stoma, another complication associated with in-
complete fecal diversion, occurs in 5–10% of cases. Most frequently it
involves the distal limb of a transverse loop colostomy, particularly when
this procedure is performed on a patient with a distended colon. Treatment
consists of closure of the stoma. In those patients in whom the loop stoma
becomes permanent, local excision of the prolapsed segment can be per-
formed and the functioning proximal component reconstructed.
In our experience with 229 patients with end-loop stomas, a total of
30 patients (13.1%) developed complications. Skin excoriation and retrac-
tion were most common, each having an incidence of 3.5%. Prolapse was
observed in only one patient, probably because the tiny aperture of the
mucous fistula prevents the distal bowel from prolapsing through it.
Loop stoma closure is associated with a morbidity reported to be be-
tween 10 and 50% and a mortality of 0 to 4%. Wound infections and anas-
tomotic leaks are among the most common complications related to loop
Diverting Stomas 137
colostomy closure. In a large series of patients with loop ileostomies, 14%
developed bowel obstructions within 30 days of closure, whereas anasto-
motic leaks and wound infections each developed in only 2.5% [7]. One
group of authors analyzed data from 93 consecutive colostomy closures in
order to compare morbidity and mortality of loop and end colostomies [6].
They concluded that loop colostomy closure is not associated with fewer
complications than closure of end colostomy, even though the latter proce-
dure takes longer and is more difficult.
Wound infections necessitate adequate drainage and aggressive local
care. Small localized anastomotic leaks may be treated conservatively with
parenteral nutrition or a low-residue diet that is high in protein and calories.
If the patient begins to show signs of systemic sepsis or complete anasto-
motic disruption, proximal diversion and drainage or exteriorization of the
anastomosis is indicated.
DISCUSSION
The indications for fecal diversion and the techniques for stoma creation and
reversal have changed over time. Currentl y, some civilia n traum a cente rs pri-
marily repair penetrating colon injuries, even those injuries to the descending
or sigmoid colon. In fact, even in cases of severe penetrating colon injuries
requiring resection, the American Association for the Surgery of Trauma
(AAST) prospective multicenter trial has shown that primary repair without
diversion is equivalent in terms of abdominal complications to diversion [3].
Most centers, however, still divert the fecal stream for rectal trauma.
The use of diverting stomas as an integral part of the restorative ileal
pouch anal anastomosis has also changed. While some surgeons still tempo-
rarily divert all pouch anal anastomoses, there is some evidence that overall
morbidity is comparable when various stoma complications are included.
When complications arise in the early postoperative period after formation
of an nondiverted ileal pouch anal anastomosis, a loop ileostomy can be
placed at a second operation without long-term problems [2].
Perhaps the most compelling question regarding diverting stomas is:
Do they completely divert the fecal stream? Several reports have addressed
this issue (Table 1). The method of study involved either feeding the patients
a barium meal or a radiolabeled tracer (chromium 51) and following the
course of the marker through the intestinal tract with sequential abdominal
radiographs or nuclear scans. As Table 1 shows, loop stomas diverted the
fecal stream effectively in almost every instance, regardless of the consis-
tency of the stool (liquid vs. solid) or a dependent location of the distal limb
on the abdominal wall. The only significant factors that led to incomplete
diversion were stomal retraction, revision of which reestablished effective
diversion, and the presence of a loop stoma for longer than 3 months.