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430 The ASCRS Manual of Colon and Rectal Surgery
• Colonoscopy has increased as a screening agent for colorectal
cancers as well as a diagnostic or therapeutic means for the
investigation for colorectal bleeding. The following characteristics of angiodysplasia may be noted:
– Angiodysplasias appear an the mucosal surface as a cherry
red lesion that is typically fl at. The lesions are greater than
2 mm in size and have a “fern-like” appearance.
– It is important to identify angiodysplasias during scope
insertion. Occasionally, the inexperienced endoscopists
may attribute colonoscopic suction trauma to an angiodysplastic area.
– Since colonoscopy has become more frequent, both left
and right sided lesions are found to occur.
Other Causes of Lower Gastrointestinal Hemorrhage
• Most of the other etiologies that cause lower gastrointestinal
bleeding (Colonic ischemia, infl ammatory bowel disease, and
colonic malignancies) are not associated with massive hemorrhage or acute symptomatic anemia.
• Typically, ischemic colitis presents with the abrupt onset of abdominal pain, followed by colic and a mucoid, bloody diarrhea.
• Infl ammatory bowel disease, Crohn’s, and ulcerative colitis
present with a change in stool patterns. Patients develop diarrhea
followed by hematochezia or melena.
• Colorectal carcinomas are associated with exophytic, ulcerative
lesions that may bleed insidiously. Only rarely does the malignant
process proceed to acute, symptomatic hemorrhage.
• Gastrointestinal stromal tumors (GIST involve the small intestine. As these lesions enlarge, they surpass their blood supply,
become ischemic, ulcerate and bleed.
• Meckel’s diverticulum occur in the distal ileum. Ectopic gastric
mucosa produces which ulcerates the adjacent intestinal wall.
• NSAIDs can cause a localized mucosal injury which frequently
bleeds
– The terminal ileum and cecum may serve as a reservoir
and harbor these agents long enough to establish the
mucosal defects.
– Diaphragm-like strictures are pathognomonic for NSAID
injuries and may result from a healing ridge related to
repeated injuries from the agents.
20. Lower Gastrointestinal Hemorrhage 431
Occult Hemorrhage
• One study noted occult bleeding in no more than 5% of
all patients admitted with lower gastrointestinal massive
hemorrhage.
• These patients may harbor angiodysplasias in the small intestine or right colon.
• Patients in this situation may benefi t from small bowel contrast
radiography or capsule endoscopy.
• Additionally, selective angiography with cecal magnifi cation
may reveal small angiodysplasias.
C. Initial Assessment, Resuscitation,
and Stabilization
• Initial placement of large bore vascular access is followed by
administration of intravenous fl uids.
• Further hemodynamic monitoring requires cardiac rhythm
monitoring and placement of a urinary catheter.
• A nasogastric tube screens for the presence of upper gastrointestinal sources for bleeding.
• Kovacs and Jensen noted 17.9% of lower gastrointestinal
hemorrhage presentations involved an upper gastrointestinal
source.
• The treatment goals for resuscitation are to restore volume and,
replete red blood cell defi ciencies for their impact on oxygen
delivery.
• In addition, all coagulopathies require reversal. Patients require
laboratory profi les that include a complete blood count, serum
electrolytes, a coagulation profi le, and a type and hold for
packed red blood cells. (Crossmatch for patients with massive
hemorrage)
• The initial specifi c diagnostic evaluation begins with a digital
anorectal examination and anoscopy. A rigid proctosigmoidoscopy will allow the examiner to evacuate the rectum of
blood and clots.
– A complete mucosal assessment serves to exclude
internal hemorrhoids, anorectal solitary ulcers, neoplasms,
and colitis.
432 The ASCRS Manual of Colon and Rectal Surgery
– If subsequent surgery becomes necessary, this evalua-
tion of the rectum and anorectal function greatly aids in
surgical decisions. A normal anorectal examination also
allows the surgeon to consider a primary rectal anastomosis as a treatment possibility.
– Identifying an anorectal source of bleeding during this
examination, often times permits therapy to control the
hemorrhage.
• Once the resuscitation demonstrates a stable patient, the next
phase of the diagnostic evaluation ensues.
• Colonoscopy and angiography offer diagnostic and therapeutic
intervention whereas nuclear scanning is purely diagnostic.
• Decisions as to which test to use depend on the clinical judgment, local expertise, severity of the event, and the current
activity of the hemorrhage.
• It may be helpful to subdivide patients into three general
clinical categories based on the history, physical, and the initial
laboratory data. Is the hemorrhagic event (1) minor and selflimited, (2) major and self-limited, or (3) major and ongoing?
– Major ongoing hemorrhage requires prompt intervention
with angiography or surgery.
– Minor, self-limited may undergo a colonic lavage and
colonoscopy within 24 h.
– Major, self-limited hemorrhage is more controversial.
These patients need a diagnostic test to determine if they
require prompt therapy or observation.
• Radionuclide imaging
– Radionuclide imaging (Fig. 20.1 ) detects the slowest
bleeding rates. It is able to detect rates of 0.1–0.5 mL/
min, making more sensitive than angiography.
– Unfortunately, the nuclear scanning cannot reliably local-
ize the site of hemorrhage
– The more frequently preferred agent for lower gas-
trointestinal hemorrhage radionuclide scanning is the
pertechnetate-tagged RBC scans. The tagged RBC scans
may cover a period of hours and allow for reimaging
within 24 h.
– Current reports suggest accuracies ranging from 24
to 91%.
– If the nuclear scan demonstrates an immediately positive
blush (within the fi rst 2 min of scanning), it is highly
predictive of a positive angiogram (60%).
20. Lower Gastrointestinal Hemorrhage 433
a
b
Fig. 20.1. Selected images from a 99mTc-labeled RBC gastrointestinal bleeding study in a patient with known diureticulosis. Images acquired at 1 min ( a )
and 14 min ( b ). Abnormal increased isotopic activity developed in the proximal
transverse colon, which progressed antegrade to the descending colon.
– If the initial images do not demonstrate a blush, the study
is highly predictive of a negative angiogram (93%) and
the need for surgery is decreased to 7%.
434 The ASCRS Manual of Colon and Rectal Surgery
– Thus, if the nuclear scan is negative, it provides objective
evidence that the patient is not actively bleeding and may
be evaluated by colonoscopy
Colonoscopy
• Many authors believe that colonoscopy has clearly demonstrated the highest effi cacy and should be the fi rst study in
patients with major bleeding that appears self-limited.
• Whether colonoscopy should be undertaken emergently
depends on the general ability to maintain a stable patient.
• Patients with extremely brisk hemorrhage require a prompt
angiogram. Colonoscopy in such patients proves diffi cult
to prep with lavage and the acute exsanguination may limit
intraluminal visualization to deploy all the therapeutic options
except for the most experienced endoscopists.
• If the patient appears stable with self-limited hemorrhage,
colonoscopy is the preferred diagnostic study.
• Longstreth reported that 80.8% of their patients had colonoscopy after electrolyte-polyethylene glycol solution purge, usually within 24 h of admission.
• The Longstreth Kaiser Permanente study demonstrated a broad
scope of etiologies (see Table 20.1 ).
• Once the endoscopist highlights a bleeding source, the region
of the intestine should be tattooed to mark the site with India
ink. In such patients, if the hemorrhage continues and fails
Table 20.1. Final diagnosis in patients hospitalized
for acute lower gastrointestinal hemorrhage.
n (%)
Colonic diverticulosis 91 (41.6)
Colorectal malignancy 20 (9.1)
Ischemic colitis 19 (8.7)
Acute colitis, unknown cause 11 (5.0)
Hemorrhoids 10 (4.6)
Postpolypectomy hemorrhage 9 (4.1)
Colonic angiodysplasia 6 (2.7)
Crohn’s disease 5 (2.3)
Other 22 (10.1)
Unknown 26 (11.9)
Total 219 (100)
20. Lower Gastrointestinal Hemorrhage 435
medical management, the tattoo greatly assists the surgeon in
localizing the hemorrhage.
• Therapeutic endoscopic options include thermal agents such as
heater probes, bipolar coagulation, and laser therapy. Injection
therapy primarily uses topical and intramucosal epinephrine.
Mechanical therapy includes endoscopically applied clips and
detachable snares.
Angiography
• Angiography is diagnostic and therapeutic in the treatment of
intestinal hemorrhage.
• Angiography is helpful in three different types of hemorrhage. First, acute, major hemorrhage with ongoing bleeding requires emergency angiography. Second, patients with
an early blush during nuclear scintigraphy may benefi t from
therapeutic angiography. Finally, angiograms may defi ne a
potential source for hemorrhage in occult and recurrent
gastrointestinal hemorrhage.
• To appreciate an angiographic blush of contrast, the study
requires a hemorrhage rate of at least 1 mL/min.
• Generally, reports demonstrate yields that range from 40 to 78%.
• Angiography provides highly accurate localization of the site
of bleeding (Fig. 20.2 ) and the angiographic blush may suggest
a specifi c etiology, but it lacks the accuracy of colonoscopy.
• In therapeutic angiography hemorrhagic site may receive
highly selective, intraarterial vasopressin infusion.
• Vasopressin controls bleeding in as many as 91% of patients.
However, bleeding may recur in as many as 50% of patients
once the vasopressin is tapered.
• Angiographic technology also allows for arterial embolization
to control hemorrhage. Superselective mesenteric angiography
with microcatheters allows for embolization of the vasa recta
of the intestine, vessels as small as 1 mm.
• Embolization therapy provides immediate arrest of the bleeding. Embolization uses a combination of agents to control
bleeding including Gelfoam pledgets, coils, and polyvinyl
alcohol particles.
• Data suggest that angiodysplasias have multiple feeding vessels which make embolization diffi cult and may contribute to
recurrence.
436 The ASCRS Manual of Colon and Rectal Surgery
Fig. 20.2. Angiogram demonstrating extravasation (hemorrhage) in cecum.
Operative Therapy
• Surgical therapy for massive lower intestinal bleeding is rare,
often defi nitive, and associated with signifi cant mortality.
• If the patient is hemodynamically unresponsive to the initial
resuscitation, then radiographic, radionuclide, and endoscopic
evaluations are usurped by the need for urgent surgery.
• Other patients may have the site of hemorrhage localized, yet the
available therapeutic interventions fail to control the bleeding.
• Bender noted a reduced mortality (7%) for patients requiring
less than ten units of blood. The mortality increased to 27% for
patients in excess of ten units.
20. Lower Gastrointestinal Hemorrhage 437
• Therefore, once a patient reaches 6–7 units during the resuscitation and the hemorrhage remains ongoing, surgical intervention
becomes eminent.
• All patients require an open laparotomy with a thorough
examination of the entire intestine.
• The fi rst objective at operation focuses on the location of the
intraluminal blood with the hope of segmentally isolating the
possible sources of bleeding. If the colon visually appears fi lled
with blood and the small intestine remains spared, the surgeon must still examine the entire abdomen and then focus
on colonic sources of bleeding. If the small bowel contains
blood, then the operative team has a larger area of concern
that needs inspection.
• Palpation of the intestine may demonstrate etiologies such
as a Meckel’s diverticulum, ileitis, colitis, or a GIST.
• Intraoperative endoscopy is a technically diffi cult endeavor.
A team approach with two surgeons or the availability of an
experienced endoscopist is important to identify the elusive
lesions causing the hemorrhage.
• If the source of bleeding cannot be found, and it appears to
arise from the colon, the surgeon should perform a subtotal
or total colectomy. Stable patients will tolerate a primary
ileosigmoid or ileorectal anastomosis in this circumstance.
• Unstable patients require an end ileostomy with closure of
the rectal stump or a mucous fi stula. Once stable, the patient
may return for ileostomy closure.
• The rectum and sigmoid colon require reexamination endo-
scopically to assure no bleeding persists.
• The key concerns with operative management are, fi rst, a
delay in the decision to operate until the hemorrhage reaches
a critical point beyond ten units of blood. This seems to
contribute to the high mortality rate. Second, mortality rates
for patients requiring urgent surgery consistently reach a
range hovering between 10 and 35%.
• The rates of recurrence increase if a surgeon elects to perform
a limited right or left colectomy without precise localization
of the hemorrhage. Limited segmental colectomies continue
to have high mortality rates and excessive persistent bleed
rates of 20%. A total colectomy offers the same mortality
with a lower chance of recurrent or persistent hemorrhage.
438 The ASCRS Manual of Colon and Rectal Surgery
D. New Frontiers
• Horton and Fishman commented about the advanced imaging
within computerized tomography. Current thinly sliced, fast
image acquisition combined with three-dimensional software
packages has revolutionized the imaging of the vascular tree.
However, these procedures are diagnostic, not therapeutic.
• Magnetic resonance angiogram creates images using the
bright signal from blood. The three-dimensional images are
reconstructed using computerized imaging to project a twodimensional image that mimics a conventional angiogram.
Further improvement develops from contrast-enhanced magnetic resonance angiography (CEMRA). With current techniques, the resultant images are not as specifi c or as refi ned
as an angiogram.
• Wireless capsular endoscopy is an ideal diagnostic adjunct for
patients with occult hemorrhage.
• The evaluation and management of lower gastrointestinal hemorrhage remains a challenge for surgeons. An algorithm summarizing the management is provided in Fig. 20.3 .
Fig. 20.3. Algorithm for the management of lower gastrointestinal hemorrhage.
21. Endometriosis
A. Introduction
• Endometriosis is a disease characterized by the presence of
endometrial glands and stroma outside the uterine cavity. It
is one of the most common conditions requiring surgery for
women during their reproductive years.
• The degree of symptoms varies widely and does not always
correspond to the extent of pathology encountered at surgery.
• Diagnosis is typically made or confi rmed at laparoscopy or
during laparotomy.
• Colon and rectal surgeons often become involved in the
management of patients with intestinal endometriosis. This
involvement may occur as a result of a combined procedure
with a gynecologist or in management of an endometrioma
masquerading as a neoplastic or infl ammatory lesion.
B. Epidemiology
• The true prevalence of endometriosis is unknown.
• Various authors have estimated that up to 15% of all women
of reproductive age and one-third of infertile women have
endometriosis.
• Although endometriosis is primarily a disease of the reproductive years, the widespread use of exogenous estrogens and
increasing obesity in our society have made it more prevalent
in postmenopausal women.
• Conversely, there is a decrease in the incidence of the disease
when women use oral contraceptives or experience multiple
pregnancies.
D.E. Beck et al. (eds.), The ASCRS Manual of Colon and Rectal Surgery, 439
DOI: 10.1007/978-0-387-73440-8_21, © Springer Science + Business Media, LLC 2009
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