Slide 1

Colon, Anus, Rectum


Slide 2

Random animal/human evacuating
bowels


Slide 3

Embryology and Anatomy
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Embryology
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Starts the fourth week of gestation
derived from the endoderm
three segments: foregut, midgut, and hindgut
midgut and hindgut contribute to the colon, rectum, and anus
Hindgut - distal transverse colon, descending colon, rectum, and
proximal anus all blood supply from IMA

Anatomy
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anatomically and functionally divided into the colon, rectum, and
anal canal
five distinct layers: mucosa, submucosa, inner circular muscle,
outer longitudinal muscle (tenea coli), and serosa (not present in
mid and lower rectum)


Slide 4

Colon
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Terminal ileum 3 to 5 ft to the rectum
Rectosigmoid junction (level of the sacral
promontory) point at which the three teniae coli
coalesce
Cecum is the widest diameter (normally 7.5 to
8.5 cm) and thinnest muscular wall (set up to
perf)
Sigmoid colon has a narrow caliber, making it
the most vulnerable to obstruction


Slide 5

Arterial Supply
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SMA 
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Ileocolic artery (absent in up to 20% of people),
terminal ileum and proximal ascending colon
Right colic artery - ascending colon
Middle colic artery - transverse colon

IMA 
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Left colic artery - descending colon
Sigmoidal branches - sigmoid colon
Superior rectal artery - proximal rectum
Communicate via the marginal artery of Drummond,
complete in only 15 to 20% of people


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Slide 7

Veins, Lymphatics, and Innervation
Veins

Veins of the colon parallel their corresponding arteries (except IMV) and bear the
same terminology

Inferior mesenteric vein ascends in the retroperitoneal plane over the psoas muscle,
posterior to the pancreas to join the splenic vein. (During a colectomy, mobilized
independently and ligated at the inferior edge of the pancreas)
Lymphatic Drainage

Muscularis mucosa -> follow the regional arteries. Lymph nodes are found on the
bowel wall (epicolic), along the inner margin of the bowel adjacent to the arterial
arcades (paracolic), around the named mesenteric vessels (intermediate), and at the
origin of the superior and inferior mesenteric arteries (main).
Nerve Supply

Sympathetic (inhibitory) and parasympathetic (stimulatory) nerves, which parallel the
course of the arteries. Sympathetic nerves arise from T6–T12 and L1–L3. Vagus
nerve ->parasympathetic innervation to the right and transverse colon;
parasympathetic nerves to the left colon arise from sacral nerves S2–S4 to form the
nervi erigentes.


Slide 8

Anorectal
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Rectum -12 to 15 cm in length
Valves of Houston - three distinct submucosal folds
Posteriorly -presacral fascia,
Anteriorly - Denonvilliers' fascia
Lateral ligaments support the lower rectum
Surgical anal canal measures 2 to 4 cm (anorectal junction to anal verge)
Dentate or pectinate line transition columnar rectal mucosa and squamous
anoderm, surrounded by longitudinal mucosal folds, known as the columns
of Morgagni, (anal crypts empty here, source of cryptoglandular abscesses)
Inner smooth muscle is thickened and comprises the internal anal sphincter
Deep external anal sphincter is an extension of the puborectalis muscle
Puborectalis, iliococcygeus, and pubococcygeusmuscles form the levator ani
muscle


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Slide 10

Anorectal Vascular Supply
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Superior rectal artery <- inferior
mesenteric artery (upper rectum)
Middle rectal artery <- internal iliac
Inferior rectal artery <- internal pudendal
<- internal iliac artery.
Rich collaterals


Slide 11

Veins and Lymphatics
Venous
 Superior rectal vein -> inferior mesenteric -> portal system
 Middle rectal vein -> internal iliac vein
 Inferior rectal vein -> internal pudendal vein -> internal iliac vein
 Submucosal plexus deep to the columns of Morgagni forms the
hemorrhoidal plexus and drains into all three veins.
Anorectal Lymphatic Drainage
 Parallels the vascular supply
 Upper and middle rectum -> inferior mesenteric nodes
 Lower rectum -> inferior mesenteric and internal iliac nodes
Anal canal
 Proximal to the dentate line -> inferior mesenteric and internal iliac
nodes
 Distal -> inguinal nodes, inferior mesenteric and internal iliac nodes


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Slide 13

Anorectal Nerve Supply
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Sympathetic - L1–L3 -> preaortic plexus -> hypogastric
plexus combine with ->
Parasympathetic (nervi erigentes) S2–S4 to form the
pelvic plexus.
Sympathetic and parasympathetic fibers then supply the
anorectum and adjacent urogenital organs.
The internal anal sphincter is innervated by sympathetic
and parasympathetic nerve fibers; both inhibit sphincter
contraction.
The external anal sphincter and puborectalis muscles are
innervated by the inferior rectal branch of the internal
pudendal nerve.


Slide 14

Normal Physiology
Fluid and Electrolyte Exchanges
 The colon is a major site for water absorption and electrolyte
exchange.
 90% of the water contained in ileal fluid is absorbed in the colon
(1000 to 2000 mL/d), and up to 5000 mL of fluid can be absorbed
daily
 Sodium is absorbed actively via a Na-K ATPase. The colon can
absorb up to 400 mEq of sodium per day.
 Water accompanies the transported sodium and is absorbed
passively along an osmotic gradient.
 Potassium is actively secreted
 Chloride is absorbed actively via a chloride–bicarbonate exchange.
 Bacterial degradation of protein and urea produces ammonia.
Ammonia is subsequently absorbed and transported to the liver.


Slide 15

Colonic Microflora and Intestinal
Gas
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Approximately 30% of fecal dry weight is composed of bacteria
(1011 to 102 bacteria/g of feces).
Anaerobes predominant
Bacteroides species are the most common (1011 to 1012
organisms/mL) > Escherichia coli are the most numerous aerobes
(108 to 1010 organisms/mL). Breakdown of carbs, bilirubin, etc.
Short-chain fatty acids (acetate, butyrate, and propionate) are
produced by bacterial fermentation of dietary carbohydrates, lack
may result in mucosal atrophy and "diversion colitis."
Produce vitamin K.
Hold off Clostridium difficile and other invaders
Intestinal gas arises from swallowed air, diffusion from the blood,
and intraluminal production.


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Slide 17

Motility
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No cyclic motor activity characteristic of the migratory motor complex. Instead, the colon displays
intermittent contractions of either low (delay colonic transit) or high amplitude (move contents).
Defecation
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Distention of the rectum causes a reflex relaxation of the internal anal sphincter (the rectoanal
inhibitory reflex) that allows the contents to make contact with the anal canal. This "sampling
reflex" allows the sensory epithelium to distinguish solid stool from liquid stool and gas.

Coordination of increasing intra-abdominal pressure via the Valsalva maneuver, increased rectal
contraction, relaxation of the puborectalis muscle, and opening of the anal canal.
Continence
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At rest, the puborectalis muscle creates a "sling" around the distal rectum, forming a relatively
acute angle that distributes intra-abdominal forces onto the pelvic floor. With defecation, this
angle straightens, allowing downward force to be applied along the axis of the rectum and anal
canal.

Internal sphincter is responsible for most of the resting, involuntary sphincter tone (resting
pressure).
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External sphincter is responsible for most of the voluntary sphincter tone (squeeze pressure).
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Branches of the pudendal nerve innervate both the internal and external sphincter.


Slide 18

Tools of the Trade
Anoscopy
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Anal canal.
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8cm but variable
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Anal procedures such as rubber band ligation or sclerotherapy of hemorrhoids
Proctoscopy
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Rectum and distal sigmoid colon
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25 cm in length.
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Polypectomy, electrocoagulation, or detorsion of a sigmoid volvulus
Flexible Sigmoidoscopy
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Colon and rectum (to splenic flexure)
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60 cm in length
Colonoscopes
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100 to 160 cm in length
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Entire colon and terminal ileum
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Bowel preparation, conscious sedation
Capsule Endoscopy
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Images transmitted by radiofrequency
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Primarily small bowel lesions


Slide 19

Imaging
Plain X-Rays and Contrast Studies
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Free intra-abdominal air, bowel gas patterns suggestive of small or large bowel obstruction, and
volvulus.
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Contrast studies are useful for evaluating obstructive symptoms, delineating fistulous tracts, and
diagnosing small perforations or anastomotic leaks.
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Gastrografin –less detail, water soluble, use if perforation
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Double-contrast barium enema 70 to 90% sensitive for the detection of mass lesions greater than
1 cm in diameter. (back-up examination if colonoscopy is incomplete)
Computed Tomography
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Good for extraluminal disease
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Perforation or anastomotic leak, nonspecific findings such as bowel wall thickening or mesenteric
stranding may suggest inflammatory bowel disease, enteritis/colitis, or ischemia..
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Not good for intraluminal pathology
Virtual Colonoscopy/Computed Tomography Colography
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Helical CT and three-dimensional reconstruction to detect intraluminal colonic lesions. Oral bowel
preparation, oral and rectal contrast, and colon insufflation
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Approaches colonoscopy’s sensitivity
Magnetic Resonance Imaging
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Detecting bony involvement or pelvic sidewall extension of rectal tumors, determines the extent
of spread of rectal cancer into adjacent structures
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Detection and delineation of complex fistulas in ano


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Slide 21

Imaging
Positron Emission Tomography
 Imaging tissues with high levels of anaerobic glycolysis (malignant
tumors)
 F-fluorodeoxyglucose
 Adjunct to CT in the staging of colorectal
Angiography
 Detection of bleeding within the colon or small bowel.
 Must be relatively brisk (approximately 0.5 to 1.0 mL per minute)
 If identified, infusion of vasopressin or angiographic embolization
can be therapeutic.
Endorectal Ultrasound
 Evaluate the depth of invasion of neoplastic lesions in the rectum.
 Can detect enlarged perirectal lymph nodes


Slide 22

Laboratory Studies
Fecal Occult Blood Testing
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Screening test for colonic neoplasms in asymptomatic, average-risk
individuals.
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Serial testing, colorectal malignancies will bleed intermittently
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Red meat, some fruits and vegetables, and vitamin C will produce a falsepositive result

Any positive FOBT mandates further investigation, usually by colonoscopy.
Stool Studies
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Stool studies often are helpful in evaluating the etiology of diarrhea.
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Wet-mount - fecal leukocytes <- colonic inflammation or the presence of an
invasive organism such as invasive E. coli or Shigella.
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Stool cultures can detect pathogenic bacteria, ova, and parasites.
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C. difficile colitis is diagnosed by detecting bacterial toxin or PCR
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Steatorrhea may be diagnosed by adding Sudan red stain to a stool sample.


Slide 23

Tumor Markers
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Carcinoembryonic antigen (CEA) 60 to
90% with colorectal cancer
Not an effective screening tool
Follow to detect early recurrence of
colorectal cancer
No survival benefit has yet been proven.


Slide 24

Pain!!!!!!!!!!
Abdominal pain
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Differential: obstruction (either inflammatory or neoplastic), inflammation,
perforation, or ischemia.
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Plain x-rays and judicious use of contrast studies and/or a CT
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Gentle retrograde contrast studies (barium or Gastrografin enema) sigmoidoscopy
and/or colonoscopy (ischemic colitis, infectious colitis, and inflammatory bowel
disease)
Pelvic pain
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Distal colon and rectum or from adjacent urogenital structures.
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Tenesmus may result from proctitis or from a rectal or retrorectal mass.
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Cyclical pain associated with menses= endometriosis.
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Pelvic inflammatory peridiverticular abscess or periappendiceal abscess into the pelvis
may also cause pain.
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CT scan and/or MRI, proctoscopy, laparoscopy
Anorectal pain
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Most often anal fissure, perirectal abscess and/or fistula, or a thrombosed
hemorrhoid >> anal canal neoplasms, perianal skin infection.
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Proctalgia fugax results from levator spasm
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Physical examination is key, (DRE)


Slide 25

Lower Gastrointestinal Bleeding
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ABCs and adequate resuscitation.
Correct coagulopathy and/or thrombocytopenia
Most common source of GI hemorrhage is upper GI: esophageal, gastric, or
duodenal, so nasogastric aspiration should always be performed
Not negative unless return of bile suggests that the source of bleeding
is distal to the ligament of Treitz.
EGD if not negative
Anoscopy and/or limited proctoscopy for hemorrhoidal bleeding.
Technetium-99–tagged red blood cell scan is extremely sensitive and is able
to detect as little as 0.1 mL/h of bleeding but imprecise.
Angiography, vasopressin or angioembolization may be
therapeutic, catheter can be left in the bleeding vessel to allow localization
at the time of laparotomy.
Colonoscopy if stable, cautery or injection of epinephrine
Colectomy may be required if bleeding persists, segmental resection is
preferred if the bleeding source can be localized.
"Blind" subtotal colectomy may very rarely be required, must r/o rectal
source


Slide 26

Occult Blood Loss
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Presents as iron-deficiency anemia or +
FOBT, if positive do colonoscopy
Neoplasms bleed intermittently
Hematochezia -> hemorrhoids (painless
(internal), bright-red rectal bleeding with bowel
movements) or fissure (sharp, knife-like pain
and bright-red rectal bleeding with bowel
movements)
Digital rectal examination, anoscopy, and
proctosigmoidoscopy, if nothing found, do
colonoscopy.


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Slide 28

Constipation and Obstructed
Defecation
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Extremely common (4 million in U.S.A.)
Metabolic, pharmacologic, endocrine, psychological, and neurologic
contribute
Exclude stricture or mass lesion by colonoscopy or barium enema
Evaluation focuses on differentiating slow-transit constipation
(radiopaque markers) from outlet obstruction (anorectal manometry
and EMG of the puborectalis)
Defecography can identify rectal prolapse, intussusception,
rectocele, or enterocele.
Medical management is the mainstay: fiber, increased fluid intake,
and laxatives
Outlet obstruction -> biofeedback
Subtotal colectomy is considered only for patients with severe slowtransit constipation (colonic inertia) refractory to maximal medical
interventions -> complaints of diarrhea, incontinence, and
abdominal pain.


Slide 29

Diarrhea
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Further investigation is warranted if diarrhea is
chronic or is accompanied by bleeding (colitis) or
abdominal pain
Infection (invasive E. coli, Shigella, Salmonella,
Campylobacter, Entamoeba histolytica, or C.
difficile) ->stool wet-mount and culture
Inflammatory bowel disease (ulcerative colitis or
Crohn's colitis) -> scope
Ischemia -> scope (if stable)


Slide 30

Chronic diarrhea
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Chronic ulcerative colitis, Crohn's colitis,
infection, malabsorption, and short-gut
syndrome can cause chronic diarrhea.
Carcinoid syndrome and islet cell tumors
(VIP, somatostatinoma, gastrinoma), large
villous lesions
Biopsies should be taken even if the
colonic mucosa appears grossly normal.


Slide 31

Irritable bowel syndrome
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Crampy abdominal pain, bloating, constipation,
and urgent diarrhea.
No underlying anatomic or physiologic
abnormality.
Diagnosis of exclusion
Dietary restrictions and avoidance of caffeine,
alcohol, and tobacco may help to alleviate
symptoms.
Antispasmodics and bulking agents may help


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Slide 33

Emergency Resection
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Obstruction, perforation, or hemorrhage.
Bowel is almost always unprepared and the patient may be unstable.
Attempt should be made to resect the involved segment along with its
lymphovascular supply.
Right colon or proximal transverse colon, a primary ileocolonic anastomosis
usually can be performed safely as long as the remaining bowel appears
healthy and the patient is stable.
Left-sided tumors-resection and end colostomy, with or without a mucus
fistula.
Increasing data for primary anastomosis without a bowel preparation or
with an on-table lavage, w/w/o diverting ileostomy, may be equally safe in
this setting.
Subtotal colectomy with a small bowel to rectosigmoid anastomosis if the
proximal colon looks unhealthy
Resection and diversion (ileostomy or colostomy) remains safe and
appropriate if the bowel looks compromised or if the patient is unstable,
malnourished, or immunosuppressed


Slide 34

Minimally Invasive Techniques of
Resection
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Laparoscopically or with hand-assisted laparoscopy.
Improved cosmetic result, decreased postoperative pain,
earlier return of bowel function, and possible decrease
in immunosuppressive impact
Most studies have demonstrated equivalence between
laparoscopic and open resection in terms of extent of
resection.
Pequire longer operative time than do open procedures.
Return of bowel function and length of hospital stay are
highly variable, but appear to be better.


Slide 35

Procedures
Ileocolic Resection

Resection of terminal ileum, cecum, and appendix

Benign lesions or incurable cancers arising in the terminal ileum, cecum, and,
occasionally, the appendix

Ileocolic vessels are ligated and divided.

Primary anastomosis distal small bowel to ascending colon

Most distal ileum needs to be resected
Right Colectomy

Most appropriate operation for curative intent resection of proximal colon carcinoma.

Ileocolic vessels, right colic vessels, and right branches of the middle colic 10 cm of
terminal ileum included
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Ileal-transverse colon anastomosis
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Extended right colectomy for curative for lesions at the hepatic flexure or proximal
transverse colon
Transverse Colectomy
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Ligating the middle colic vessels
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Colocolonic anastomosis
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Extended right colectomy safer


Slide 36

Procedures
Left Colectomy
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For lesions in distal transverse colon, splenic flexure, or descending colon

Left branches of the middle colic vessels, the left colic vessels, and the first branches of the
sigmoid vessels are ligated.

Colocolonic anastomosis usually can be performed.
Sigmoid Colectomy

Divide sigmoid branches of the inferior mesenteric artery

Entire sigmoid colon should be resected to the level of the peritoneal reflection

Descending colon to upper rectum
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Full mobilization of the splenic flexure for tension-free anastomosis
Total and Subtotal Colectomy

Fulminant colitis, attenuated FAP (AFAP), or synchronous colon carcinomas

Divide ileocolic vessels, right colic vessels, middle colic vessels, and left colic vessels leave
superior rectal vessels
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Subtotal colectomy with ileosigmoid anastomosis – distal sigmoid left

Sigmoid completely removed- total abdominal colectomy with ileorectal anastomosis

End-ileostomy - remaining sigmoid or rectum made into mucus fistula or Hartmann pouch.
Total Proctocolectomy

Colon, rectum, and anus are removed and the ileum is brought to the skin as a Brooke ileostomy.

Restorative Proctocolectomy (Ileal Pouch Anal Anastomosis)

Colon and rectum resected, but the anal sphincter muscles portion of the distal anal canal are
preserved.


Slide 37

Procedures
High Anterior Resection

Distal sigmoid colon and upper rectum for benign lesions and disease at the
rectosigmoid junction such as diverticulitis.

Primary anastomosis (usually end-to-end) between the colon and rectal
stump with a short cuff of peritoneum surrounding its anterior two thirds
Low Anterior Resection

Lesions in the upper and midrectum.

The rectosigmoid is mobilized, the pelvic peritoneum is opened

Dissection to the anorectal ring

Requires mobilization of the splenic flexure
Extended Low Anterior Resection

For distal rectum lesions but several centimeters above the sphincter

Coloanal anastomosis
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Creation of a temporary ileostomy
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Can create colon J-pouch if no sphincter damage


Slide 38

Procedures
Hartmann's Procedure and Mucus Fistula

colostomy or ileostomy is created and the distal colon or rectum is left as a blind
pouch

mucus fistula if enough bowel present
Abdominoperineal Resection

entire rectum, anal canal, and anus with construction of a permanent colostomy from
the descending or sigmoid colon

Anastomoses

end-to-end (roughly the same caliber), end-to-side (one limb of bowel is larger than
the other), side-to-end (proximal bowel is of smaller caliber than the distal bowel,
ileorectal), or side-to-side (ileocolic and small bowel anastomoses)

handsewn (single or double layer(continuous inner layer and an interrupted outer
layer)) or stapled (particularly useful for creating low rectal or anal canal
anastomoses)

none has been proven to be superior

submucosal layer of the intestine provides the strength of the bowel wall

NO tension in a normotensive

Highest risk - distal rectal or anal canal, involve irradiated or diseased intestine, or
are performed in malnourished, ill patients.


Slide 39

Ostomies
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Temporary or permanent, end-on or a
loop
Placement and construction are crucial for
function
Located within the rectus muscle to
minimize the risk of a postoperative
parastomal hernia
Must be in plain sight
Preoperative evaluation by ostomy nurse
(sight and teaching)


Slide 40

More Ostomy
Temporary Ileostomy - loop ileostomy

Subsequent closure often can be accomplished without a formal laparotomy

Flexible endoscopy exam and a contrast enema (Gastrografin) are recommended
before closure
Permanent Ileostomy

After total proctocolectomy or in patients with obstruction.

End ileostomy is the preferred configuration

Stitches often are used to secure the bowel to the posterior fascia.
Complications of Ileostomy
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Stoma necrosis - skeletonizing or tight fascial defect

Necrosis below the level of the fascia requires surgical revision

Stoma retraction may occur early or late

Dehydration fluid and electrolyte abnormalities, keep at less than 1500 mL/d

Bulk agents and opioids (Lomotil, Imodium, tincture of opium) are useful. Obstruction

Parastomal hernia - symptomatic should be repaired, re-siting the stoma to the
contralateral side of the abdomen.
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Prolapse (rare)


Slide 41

Colostomy
Most end colostomies >> loop colostomies (too bulky and prolapse is more
likely)

Should be matured in a Brooke fashion

Mucus fistula or Hartmann's pouch

Closure generally requires laparotomy
Complications of Colostomy

Necrosis management similar to ileostomy

Retraction less problematic with a colostomy

Obstruction is unusual

Parastomal hernia is the most common late complication of a colostomy
(repair if it is symptomatic)
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Prolapse occurs rarely
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Dehydration is rare
Functional Results
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Usually excellent

Uncommon diarrhea and bowel frequency.
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Slide 42

Positioning

Most abdominal colectomies can be performed in the supine position. Anterior and
APRs require lithotomy positioning.
Bowel Preparation

Decreasing the bacterial load in the colon and rectum (not proven)

Most commonly used regimens include polyethylene glycol (PEG) solutions or sodium
phosphate, equally efficacious in bowel cleansing.

Oral antibiotics to decreasing the bacterial load of the colon. never been proven to
decrease postoperative infectious complications.

Ideally, a stoma should be placed in a location that the patient can easily see and
manipulate, within the rectus muscle, and below the belt line (see Fig. 29-15). In
emergencies, placement high on the abdominal wall is preferred to a low-lying site.
Ureteral Stents

Useful for identifying the ureters intraoperatively

Invaluable in reoperative pelvic surgery or when there is significant retroperitoneal
inflammation

Lighted stents may be helpful in laparoscopic resections


Slide 43

Inflammatory Bowel Disease
Epidemiology

Ulcerative colitis to 15 people per 100,000

Crohn's disease is slightly lower, one to five people per 100,000 population. Both have bimodal incidence, 15 to 30 years and ages 55 to
60 years.

15% indeterminate colitis.
Etiology

none are proven.

Family history 10 to 30% have a family member with the same disease

Autoimmune vs infectious

Pathology and Differential Diagnosis
Ulcerative colitis is a mucosal process

mucosa atrophic and friable, crypt abscesses friable, inflammatory pseudopolyps. Proctitis (just rectum) to pancolitis.

does not involve the small intestine, but "backwash ileitis

continuous involvement of the rectum and bloody diarrhea and crampy abdominal pain, tenesmus. Severe abdominal pain and fever =
fulminant colitis or toxic megacolon. Dx with colonoscopy and mucosal biopsy.
Crohns disease

transmural and can affect any part of the GI tract from mouth to anus. Mucosal ulcerations, noncaseating granulomas Chronic
inflammation may ultimately result in fibrosis, strictures, and fistulas in either the colon or small intestine. Colonoscopy deep serpiginous
ulcers and a "cobblestone" appearance. Skip lesions and rectal sparing are common.

diarrhea, crampy abdominal pain, and fever. Strictures may produce symptoms of obstruction. Perianal Crohn's disease may present with
pain, swelling, and drainage from fistulas or abscesses.
Extraintestinal Manifestations

Fatty infiltration of the liver is present in 40 to 50% cirrhosis is found in 2 to 5%.

40 to 60% with primary sclerosing cholangitis have ulcerative colitis. Biliary carcinoma fromlong standing disease

Arthritis 20 times greater than in the general population.

Sacroiliitis and ankylosing spondylitis are associated with inflammatory bowel disease

Erythema nodosum is seen in 5 to 15%

Women are affected three to four times more frequently than men. Pyoderma gangrenosum is an uncommon but serious.

Up to 10% will develop ocular lesions.


Slide 44

Principles of Nonoperative Management

Ulcerative proctitis and proctosigmoiditis salicylate and/or corticosteroid suppositories and enemas

Salicylates

Sulfasalazine (Azulfidine), 5-ASA, and related compounds are first-line agents in the medical treatment of mild to
moderate inflammatory bowel disease. cyclooxygenase and 5-lipoxygenase
Antibiotics

Metronidazole possibly helps with Crohn's colitis but Abx reserved for fulminant colitis or toxic megacolon
Corticosteroids

Corticosteroids are a key component

75 to 90% of patients will improve

Failure to wean corticosteroids is a relative indication for surgery.

Corticosteroid enemas provide effective local therapy for proctitis
Other Immunosuppressive Agents

Azathioprine and 6-mercaptopurine are antimetabolite drugs ulcerative colitis and Crohn's disease in patients who
have failed salicylate therapy or who are dependent upon or refractory to corticosteroids.

Onset of action of these drugs takes 6 to 12 weeks taken with steriods

Cyclosporine interferes with T-cell function.

Not routinely used to treat inflammatory bowel disease, helps with refractory UC and Crohns

Methotrexate is a folate antagonist efficacy of this agent is unproven

Infliximab (Remicade) is a monoclonal antibody against tumor necrosis factor alpha. moderate to severe Crohn's
disease Recurrence is common
Nutrition

Patients with inflammatory bowel disease often are malnourished. Pain, obstruction, diarrhea inflammatory
catabolic state

TPN suggested


Slide 45

Ulcerative Colitis













Characterized by remissions and exacerbations.
Insidious, with minimal bloody stools, or the onset can be abrupt, with severe
diarrhea and bleeding, tenesmus, abdominal pain, and fever.
Dx endoscopically with bx, chronic phase better, don’t perf (acute phase)
Rectum invariably involved
Pus and mucus also may be present.
Barium enema "lead pipe" colon
Emergent surgery - hemorrhage, toxic megacolon, or fulminant colitis who fail to
respond rapidly to medical therapy.
Fulminant colitis should be treated aggressively with bowel rest, hydration, broadspectrum antibiotics, and parenteral corticosteroids. No colonoscopy, barium enema,
and antidiarrheal agents are contraindicated. Deteriation or failure to improve within
24 to 48 hours mandates surgery.
Elective surgery - intractability despite maximal medical therapy, side effects not
tolerated, significant risk of developing colorectal carcinoma.
Risk of malignancy increases with pancolonic disease and the duration of symptoms
is approximately 2% after 10 years, 8% after 20 years, and 18% after 30 years.
Long-standing ulcerative colitis undergo colonoscopic surveillance with multiple (40 to
50), random biopsies to identify dysplasia before invasive malignancy develops (flat
polyps)


Slide 46

Ulcerative Colitis
Annual surveillance after:





8 years in patients with pancolitis
15 years in patients with left-sided colitis
dysplasia - should be advised to undergo proctocolectomy
controversy prophylactic proctocolectomy for chronic UC for >10 years

Emergent Operation

Fulminant colitis or toxic megacolon

Total abdominal colectomy with end ileostomy>>>total proctocolectomy
Elective Operation

Include resection of the rectum

Indeterminate -> abdominal colectomy with ileorectal anastomosis

Total proctocolectomy with end ileostomy has been the "gold standard" for
patients with chronic ulcerative colitis.

restorative proctocolectomy with ileal pouch–anal anastomosis has become
the procedure of choice


Slide 47

Crohn's Disease


















Exacerbations and remissions.
Any portion of the intestinal tract, from mouth to anus, impossible to remove all of the at-risk
intestine
Rectal sparing occurs in 40%
Terminal ileum and cecum (ileocolic Crohn's disease) involved 41%
Internal fistulas (require resection of the segment of bowel), chronic strictures (resection or
stricturoplasty)
Length of bowel removed should be minimized.
Bowel should be resected to an area with grossly normal margins ONLY
Stoma should be strongly considered in any patient who is hemodynamically unstable, septic,
malnourished, or receiving high-dose immunosuppressive therapy and in patients with extensive
intra-abdominal contamination.
Ileocolic and Small Bowel Crohn's Disease
Most common indications for surgery are internal fistula or abscess (30 to 38% of patients) and
obstruction (35 to 37% of patients).
Drainage of abscess(es) and antibiotics,
Isolated chronic strictures also should be resected. In patients with multiple fibrotic strictures that
would require extensive small bowel resection, stricturoplasty is a safe and effective alternative to
resection.
Recurrence 50% in 10 yrs


Slide 48











Crohn's colitis (especially pancolitis) carries nearly the same risk for
cancer as ulcerative colitis.
Ileal pouch–anal reconstruction is not recommended
perianal disease occurs in 35% of all patients with Crohn's disease
fissure from Crohn's disease is particularly deep more like an ulcer.
They often are multiple and located in a lateral position
Treatment of anal and perianal Crohn's disease focuses on
alleviation of symptoms. should not do surgery unless forced, risk of
creating chronic, nonhealing wounds.
Drain abscesses, mushroom catheters and liberal use of setons,
advancement flaps if minimal disease, intractable perianal sepsis
requires proctectomy.
Infliximab and others have shown some efficacy in healing chronic
fistulas (drain any and all abscesses before starting)


Slide 49

Indeterminate Colitis




15% of patients with IBD characteristics of
both diseases
Indications for surgery are the same, treat
like Crohns


Slide 50


Slide 51

Diverticular Disease







Majority false diverticula, mucosa and
muscularis mucosa has herniated through
the colonic wall, between the taeniae coli,
where the main blood vessels penetrate
the colonic wall
Extremely common in US (50% over 50
years)
Sigmoid colon is the most common site
Lack of dietary fiber


Slide 52

Inflammatory Complications
(Diverticulitis)








Left-sided abdominal pain, with or without
fever, and leukocytosis
Occurs in 10 to 25% of people with
diverticulosis.
Broad spectrum of disease (out pt tx vs
emergent OR)
Free air on films, CT scan pericolic
inflammation, phlegmon, or abscess.


Slide 53

Uncomplicated Diverticulitis











LLQ pain and tenderness.
CT findings include pericolic soft tissue stranding, colonic wall thickening,
and/or phlegmon.
Outpatient therapy with broad-spectrum oral antibiotics (7 to 10 days) and
a low-residue diet..no improvewment in 48 to 72 hours think abscess
50 to 70% will have no further episodes.
elective sigmoid colectomy often is recommended after the second episode
of diverticulitis,
Resection often has been recommended after the first episode in very
young patients or immunosupressed and often is recommended after the
first episode of complicated diverticulitis.
carcinoma must be excluded by colonoscopy
Sigmoidoscopy or colonoscopy is recommended 4 to 6 weeks after
recovery.
sigmoid colectomy with a primary anastomosis is the procedure of choice.


Slide 54

Complicated Diverticulitis
abscess, obstruction, diffuse peritonitis (free perforation), or fistulas between the colon and adjacent structures.
Hinchey staging system

Stage I includes colonic inflammation with an associated pericolic abscess; stage II includes colonic inflammation
with a retroperitoneal or pelvic abscess

stage III is associated with purulent peritonitis; and stage IV is associated with fecal peritonitis.

Urgent or emergent laparotomy may be required if an abscess is inaccessible to percutaneous drainage, if the
patient's condition deteriorates or fails to improve, or if the patient presents with free intra-abdominal air or
peritonitis.

(Hinchey stages I and II) may be candidates for a sigmoid colectomy with a primary anastomosis (a one-stage
operation). In patients with larger abscesses, peritoneal soiling, or peritonitis, sigmoid colectomy with end
colostomy and Hartmann pouch is the most commonly used procedure. Sigmoid colectomy with end colostomy is
the safest procedure to perform in this emergent setting.
Fistulas

5% of patients with complicated diverticulitis develop fistulas

Colovesical >colovaginal and coloenteric fistulas>colocutaneous

Contrast enema and/or small bowel studies

malignancy, Crohn's disease, and radiation-induced fistulas.

colonoscopy or sigmoidoscopy usually is required to rule out malignancy

resection of the affected segment
Hemorrhage

erosion of the peridiverticular arteriole and may result in massive hemorrhage.

80% of patients, bleeding stops spontaneously



Slide 55


Slide 56

Adenocarcinoma and Polyps
Incidence
 Colorectal carcinoma is the most common malignancy of the GI
tract. Over 150,000 new cases are diagnosed
 Colon cancer is the second most lethal cancer in the US
 Aging
 Aging is the dominant risk factor
 rising steadily after age 50 years. 90%
 Hereditary Risk Factors
 80% sporadic, 20% known family history
 Environmental and Dietary Factors
 high in animal fat and low in fiber
 diet high in oleic acid (olive oil, coconut oil, fish oil) does not
increase risk.
 diet high in vegetable fiber appears to be protective. alcohol intake
 Obesity and sedentary


Slide 57

Risk Factors
Cigarette smoking
 Acromegaly,
 Pelvic irradiation
 Genetic Defects
Inflammatory Bowel Disease
 Ulcerative pancolitis, the risk of carcinoma is approximately 2%
after 10 years, 8% after 20 years, and 18% after 30 years. Patients
with Crohn's pancolitis have similar risk.
 Colonoscopy with multiple random mucosal biopsies has been
recommended annually after 8 years of disease for patients with
pancolitis and after 12 to 15 years of disease for patients with leftsided colitis


.


Slide 58

Genetics
APC gene

present in 80% of sporadic cases

tumor-suppressor gene

AD
K-ras

proto-oncogene

only one allele

G protein involved in intracellular GTP signal transduction.
MYH gene

base excision repair gene

biallelic deletion

AR
DCC

tumor-suppressor

gene product is poorly understood

differentiation and axonal migration

present in more than 70% of colorectal carcinomas
p53

tumor-suppressor gene

crucial for initiating apoptosis

75% of colorectal cancers


Slide 59

Neoplastic Polyps
Adenomatous polyps
 25% of the population older than 50 years of
 Lesions are dysplastic. Size and type matter
 Tubular adenomas 5% malignancy
 Villous adenomas in up to 40%.
 Tubulovillous intermediate risk (22%).
 The risk of carcinoma in a polyp larger than 2 cm is 35 to 50%.
 Pedunculated polyps are amenable to colonoscopic snare excision
 Sessile polyps are more challenging (saline lift and piecemeal snare)
 Rectal sessile polyps, transanal operative excision
 Site of sessile polypectomies should be marked by injection of
methylene blue or India ink to guide follow-up colonoscopy
 Risk perforation and bleeding.
 Colectomy if unable to remove


Slide 60

Neoplastic Polyps
Hamartomatous Polyps (Juvenile Polyps)

Usually are not premalignant.

Childhood but may occur at any age.

Bleeding > intussusception and/or obstruction

Treated by polypectomy.
Familial juvenile polyposis

Autosomal dominant

Hundreds of polyps

May degenerate into adenomas and, eventually, carcinoma. Annual screening 10 and 12 years.

Total proctocolectomy if rectal involvement
Peutz-Jeghers syndrome

Small intestine >> colon and rectum.

Melanin spots often are noted on the buccal mucosa and lips

Hamartomas, low risk, carcinoma may occasionally develop.

Surgery is reserved for obstruction or bleeding

Above and below at age 20 years then annual flexible sigmoidoscopy thereafter.
Inflammatory Polyps (Pseudopolyps)

Inflammatory bowel disease>> amebic colitis, ischemic colitis, and schistosomal colitis

Not premalignant
Hyperplastic Polyps

Extremely common

Usually are small (<5 mm)

Hyperplasia without any dysplasia, not premalignant

Large hyperplastic polyps (>2 cm) may have slight risk


Slide 61

Familial Adenomatous Polyposis












Autosomal dominant
Mutation in the APC gene, located on chromosome 5q.
Up to 25% without other affected family members
Thousands of adenomatous polyps shortly after puberty
Lifetime risk approaches 100% by age 50 years.
Flexible sigmoidoscopy of first-degree relatives of FAP patients beginning at
age 10 to 15 years has been the traditional mainstay of screening.
At risk for duodenal, periampullary carcinoma so need EGDs
Total proctocolectomy with either an end (Brooke) ileostomy vs total
abdominal colectomy with ileorectal anastomosis; and restorative
proctocolectomy with ileal pouch–anal anastomosis with or without a
temporary ileostomy.
COX-2 inhibitors (celecoxib, sulindac) may slow polyp formation
FAP may be associated with congenital hypertrophy of the retinal
pigmented epithelium, desmoid tumors, epidermoid cysts, mandibular
osteomas (Gardner's syndrome), and central nervous system tumors
(Turcot's syndrome).


Slide 62


Slide 63

Attenuated FAP






AFAP is a recently recognized variant of
FAP associated with mutations at the 3' or
5' end of the APC gene.
Patients present later in life with fewer
polyps (usually 10 to 100)
Carcinoma develops in more than 50% of
these patients


Slide 64

Hereditary Nonpolyposis Colon
Cancer (Lynch Syndrome)

















Extremely rare (1 to 3%).
Errors in mismatch repair
Autosomal dominant
Average age: 40 to 45 years
70% of affected individuals will develop colorectal cancer.
Risk of synchronous or metachronous colorectal carcinoma is 40%.
Associated with extracolonic malignancies, including endometrial, which is most common,
ovarian, pancreas, stomach, small bowel, biliary, and urinary tract carcinomas.
Diagnosis of HNPCC is made based upon family history.
The Amsterdam criteria: three affected relatives with histologically verified adenocarcinoma of
the large bowel (one must be a first-degree relative of one of the others) in two successive
generations of a family with one patient diagnosed before age 50 years.
Screening colonoscopy is recommended annually for at-risk patients beginning at either age 20 to
25 years or 10 years younger than the youngest age at diagnosis in the family, whichever comes
first.
Transvaginal ultrasound or endometrial aspiration biopsy also is recommended annually after age
25 to 35 years.
Total colectomy with ileorectal anastomosis is recommended once adenomas or a colon
carcinoma is diagnosed
Annual proctoscopy


Slide 65

Familial Colorectal Cancer
(Nonsyndromic)






10 to 15% of patients with colorectal
cancer
Approximately 6%, but rises to 12% if one
first-degree relative is affected and to
35% if two first-degree relatives
Colonoscopy is recommended every 5
years beginning at age 40 years or
beginning 10 years before the age of the
earliest diagnosed patient in the pedigree.


Slide 66

Screening
Fecal Occult Blood Testing

Reduces colorectal cancer mortality by 33% and metastatic cases by 50%. relatively insensitive,
missing up to 50% of cancers and the majority of adenomas

Specificity VERY low
Flexible Sigmoidoscopy

Screening by flexible sigmoidoscopy every 5 years may lead to a 60 to 70%

Combination of FOBT annually and flexible sigmoidoscopy every 5 years
Colonoscopy

Highly sensitive for detecting even small polyps (<1 cm) and allows biopsy, polypectomy, control
of hemorrhage, and dilation of strictures

Require mechanical bowel preparation and the discomfort

More expensive

Perforation and hemorrhage rare
Air-Contrast Barium Enema

Highly sensitive for detecting polyps greater than 1 cm

Often is combined with flexible sigmoidoscopy for screening purposes.
Computed Tomographic Colonography (Virtual Colonoscopy)

Helical CT technology and three-dimensional reconstruction

Require a mechanical bowel preparation filled with air

Sensitivity appears to be as good as colonoscopy

Colonoscopy is required if a lesion is identified

False-positive results from retained stool, diverticular disease, haustral folds


Slide 67






Current American Cancer Society
guidelines advocate screening
Beginning at age 50 years
Recommended procedures include:








Yearly FOBT
Flexible sigmoidoscopy every 5 years
FOBT and flexible sigmoidoscopy in
combination,
Air-contrast barium enema every 5 years
Colonoscopy every 10 years.


Slide 68












T stage (depth of invasion) is the single most significant predictor of
lymph node spread.
Even if confined to the bowel wall (T1 and T2) LN metastasis in 5 to
20% of cases
Through the bowel wall or into adjacent organs (T3 and T4) are
likely to have lymph node metastasis in more than 50%
Four or more involved lymph nodes predict a poor prognosis.
Upper rectum, drainage ascends along the superior rectal vessels to
the inferior mesenteric nodes. In the lower rectum, lymphatic
drainage may course along the middle rectal vessels.
Most common site of distant metastasis from colorectal cancer is the
liver.
Hematogenous spread via the portal venous system
Lung #2 site
Carcinomatosis (diffuse peritoneal metastases)


Slide 69

Preoperative Evaluation









Evaluated for synchronous tumors, usually by colonoscopy.
Synchronous disease (5%)
Rectal cancers, digital rectal examination and rigid proctoscopy
Chest/abdominal/pelvic CT scan
PET scan may be useful in evaluating lesions seen on CT scan,
Subtotal or total colectomy should be considered with presence of
synchronous cancers or adenomas or a strong family history
Minimum of 12 lymph nodes in the resected specimen are necessary
for adequate staging, more nodes are harvested have better longterm outcome
If unexpected metastatic disease is encountered at the time of a
laparotomy, the primary tumor should be resected, if technically
feasible and safe. If primary tumor is not resectable, a palliative
procedure can be performed and usually involves a proximal stoma
or bypass.


Slide 70

Stage-Specific Therapy










Stage 0 (Tis, N0, M0)

polyps should be excised completely and pathologic margins should be free of dysplasia.
Stage I: The Malignant Polyp (T1, N0, M0)

no stalk involvement resected endoscopically. lymphovascular invasion, poorly differentiated
histology, or tumor within 1 mm of the resection margin needsegmental colectomy is then
indicated.
Stages I and II: Localized Colon Carcinoma (T1–3, N0, M0)

Adjuvant chemotherapy has been suggested for selected patients with stage II disease
(young patients, tumors with "high-risk" histologic findings) (controversial)
Stage III: Lymph Node Metastasis (Tany, N1, M0)

significant risk for both local and distant recurrence, and adjuvant chemotherapy

5-fluorouracil (5-FU)–based regimens (with levamisole or leucovorin) reduce recurrences and
improve survival in this patient population
Stage IV: Distant Metastasis (Tany, Nany, M1)

Resectable metastases may benefit from resection

liver- 20% are potentially resectable for cure. Survival is improved All patients require
adjuvant chemotherapy. Lung- long-term survival benefit can be expected in 30 to 40%.

Others should be palliation.

colonic stenting for obstructing lesions of the left colon, diverting stoma.


Slide 71

Therapy for Rectal Carcinoma









More difficult to achieve negative radial margins
Local recurrence is higher than with similar stage colon cancers.
easier to treat rectal tumors with radiation.
Local Therapy
The distal 10 cm of the rectum are accessible transanally.
Transanal excision (full thickness or mucosal) is an excellent approach for
noncircumferential, benign, villous adenomas of the rectum. No LN and high
recurrence.
Radical Resection




Total mesorectal excision (TME) is dissection along anatomic planes to ensure
complete resection of the rectal mesentery during low and extended low anterior
resections.





Radical resection is preferred , attempt to obtain a 2-cm distal mural margin for curative
resections.

Less blood loss and less risk to the pelvic nerves and presacral plexus than is blunt
dissection.

When the radial margin is threatened or involved, neoadjuvant chemoradiation is
recommended.
Villous adenomas harboring carcinoma in situ (high-grade dysplasia) are ideally
treated with local excision. A 1-cm margin should be obtained.


Slide 72

Stage Specific Therapy
Stage I: Localized Rectal Carcinoma (T1–2, N0, M0)

Radical resection is strongly recommended in all good-risk patients.

Lesions with unfavorable histologic characteristics and those located in the distal third
of the rectum, in particular, are prone to recurrence.

Locally Advanced Rectal Cancer (Stages II and III)
Stage II: Localized Rectal Carcinoma (T3–4, N0, M0)

Total mesorectal resection vs stages II and III rectal cancers will benefit from
chemoradiation.
Stage III: Lymph Node Metastasis (Tany, N1, M0)

Chemotherapy and radiation either pre- or postoperatively for node-positive rectal
cancers.

Both improved local control and prolonged survival,

Most colorectal surgeons in the United States continue to recommend adjuvant or
neoadjuvant therapy for patients with locally advanced disease.

Most surgeons consider preoperative chemoradiation to be the most appropriate
therapy for locally advanced rectal cancer.75
Stage IV: Distant Metastasis (Tany, Nany, M1)

Resect isolated mets but otherwise palliative procedures (intraluminal stents,
diverting colostomy)


Slide 73

Follow-Up and Surveillance

Colonoscopy should be performed within 12 months after the diagnosis of
the original cancer, if normal, colonoscopy should be repeated every 3 to 5
years thereafter

Re-resection often is technically challenging and highly morbid, with only a
limited chance of achieving long-term survival. Highest in 2 years

CEA often is followed every 2 to 3 months for 2 years.

Between 20 and 40% for colorectal carcinoma will develop recurrent
disease.

Sentinel Lymph Node Biopsy for Colorectal Carcinoma can improve staging.
Minimally Invasive Techniques for Resection

The Clinical Outcomes of Surgical Therapy Study Group (COST), the Colon
Carcinoma Laparoscopic or Open Resection (COLOR) trial, and the United
Kingdom Medical Research Council Conventional vs. Laparoscopic-Assisted
Surgery in Colorectal Cancer (CLASSICC) trial have all shown oncologic
equivalence between open and laparoscopic techniques.


Slide 74


Slide 75

Other Neoplasms
Carcinoid Tumors

up to 25% found in the rectum.

Most benign, survival is greater than 80%.

60% of tumors greater than 2 cm in diameter distant metastases.

Proximal colon carcinoid usually more aggressive and larger by diagnosis Symptoms of carcinoid syndrome often
can be alleviated with somatostatin analogues (octreotide) and/or interferonLipomas

submucosa of the colon and rectum.

benign lesions, but rarely may cause bleeding, obstruction, or intussusception
Lymphoma

rare, but accounts for about 10% of all GI lymphomas.

bleeding and obstruction

Bowel resection
Leiomyoma

benign tumors

upper GI tract

asymptomatic>> cause bleeding or obstruction.

should be resected

Recurrence is common

Lesions >5 cm need radical resection
Leiomyosarcoma

Rare, rectum is the most common site.

bleeding and obstruction

radical resection


Slide 76

Retrorectal/Presacral Tumors
 Rare
 Often heterogeneous
 Congenital lesions are most common
 Malignancy is more common in the pediatric population
 Cysts: dermoid and epidermoid, enterogenous, meningocele and
myelomeningocele
 Solid lesions include teratomas, chordomas, neurologic tumors, or
osseus lesions.
 Present with pain (lower back, pelvic, or lower extremity), GI
symptoms, or urinary tract symptoms.
 digital rectal examination. pelvic MRI >>CT
 Biopsy is not indicated
 surgical resection


Slide 77

Anal Canal and Perianal Tumors
Cancers of the anal canal are uncommon and account for approximately 2% of all colorectal malignancies.
Major division is the dentate line: anal margin (distal) vs anal canal (proximal), lymphatics
Anal Intraepithelial Neoplasia (Bowen's Disease)

Bowen's disease refers to squamous cell carcinoma in situ of the anus.

Precursor to an invasive squamous cell carcinoma

Associated with infection with the human papillomavirus (HPV), especially HPV types 16 and 18.

high recurrence and/or reinfection rate
Epidermoid Carcinoma

cell carcinoma, cloacogenic carcinoma, transitional carcinoma, and basaloid carcinoma. Behave the same

slow-growing tumor, and

Mass effect >> pain and bleeding

Wide local excision

Chemotherapy and radiation if simple excision not possible (the Nigro protocol: 5-FU, mitomycin C, and 3000 cGy external beam
radiation)

80% cure

Recurrence usually requires radical resection (APR).

Verrucous Carcinoma (Buschke-Lowenstein Tumor, Giant Condyloma Acuminata)

Verrucous carcinoma is a locally aggressive form of condyloma acuminata.

Wide local excision
Basal Cell Carcinoma

Basal cell carcinoma of the anus is rare and resembles basal cell carcinoma elsewhere

Wide local excision is the treatment of choice

recurrence occurs in up to 30%
Melanoma

Anorectal melanoma is rare, comprising less than 1% of all anorectal malignancies and 1 to 2% of melanomas.

5-year survival is less than 10%,

radical resection (APR, no survival advantage) and wide local excision have been advocated.

adjuvant chemotherapy, biochemotherapy, vaccines, or radiotherapy may be of benefit in some patients, but efficacy remains unproven.




Slide 78

Rectal Prolapse and Solitary Rectal
Ulcer Syndrome








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Women, with a female:male ratio of 6:1.
Age, peaks in the seventh decade of life.
Incontinence and diarrhea to constipation and outlet
obstruction.
Colonoscopy or air-contrast barium enema to exclude
neoplasms or diverticular disease.
Abdominal rectopexy (with or without sigmoid resection)
offers the most durable repair, with recurrence occurring
in fewer than 10% of patients.
Perineal rectosigmoidectomy avoids an abdominal
operation preferable in high-risk patients


Slide 79


Slide 80

Volvulus
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Air-filled segment of the colon twists about its
mesentery. The sigmoid colon is involved in up
to 90% >> cecum (<20%) or transverse colon.
Reduce spontaneously, bowel obstruction,
strangulation, gangrene, and perforation.
Abdominal distention, nausea, and vomiting.
Fever and leukocytosis are heralds of gangrene
and/or perforation.
History of intermittent obstructive symptoms
and distention, suggesting intermittent chronic
volvulus.


Slide 81

Sigmoid Volvulus
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Characteristic bent inner tube, convexity of the loop lying in the
right upper quadrant
Gastrografin enema shows a narrowing at the site of the volvulus
and a pathognomonic bird's beak
Unless gangrene or peritonitis, resuscitation followed by endoscopic
detorsion with rigid proctoscope > flexible
sigmoidoscope/colonoscope
Rectal tube may be inserted to maintain decompression.
Recurrence is high (40%)
Elective sigmoid colectomy after stabilized & bowel preparation.
Clinical evidence of gangrene or perforation mandates immediate
surgical exploration without an attempt at endoscopic
decompression.
Sigmoid colectomy with end colostomy


Slide 82

Cecal Volvulus
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Rotation occurs around the ileocolic blood
vessels and vascular impairment occurs early.
Kidney-shaped, air-filled structure in the left
upper quadrant
Can almost never be detorsed endoscopically.
Surgical exploration is necessary at diagnosis
Right hemicolectomy with a primary ileocolic
anastomosis


Slide 83

Megacolon
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chronically dilated, elongated, hypertrophied large
bowel.
congenital or acquired and usually is related to chronic
mechanical or functional obstruction.
must exclude a surgically correctable mechanical
obstruction.
Hirschsprung's disease (neural crest cells)
infection or chronic constipation. (Chagas' disease)
neurologic disorders
Diverting ileostomy or subtotal colectomy with an
ileorectal anastomosis is occasionally necessary


Slide 84

Colonic Pseudo-Obstruction
(Ogilvie's Syndrome)
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Disorder in which the colon becomes massively dilated in the
absence of mechanical obstruction.
Most commonly occurs in hospitalized patients
Associated with the use of narcotics, bedrest, and comorbid disease.
Cassive dilatation of the colon (usually predominantly the right and
transverse colon) in the absence of a mechanical obstruction.
Cessation of narcotics, anticholinergics, or other medications
Strict bowel rest and IV hydration are crucial.
IV neostigmine > colonoscopic decompression often is effective.
Crucial to exclude mechanical obstruction (usually with a
Gastrografin or barium enema) before medical or endoscopic
treatment


Slide 85

Ischemic Colitis
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Most commonly in the colon
Predominately low flow and/or small vessel occlusion.
Vascular disease, diabetes mellitus, vasculitis, and hypotension.
Ligation of the inferior mesenteric artery during aortic surgery
Splenic flexure is the most common (water shed area)
Mild cases, patients may have diarrhea (usually bloody) without pain.
Severe ischemia with intense abdominal pain (often out of proportion to the clinical
examination), tenderness, fever, and leukocytosis
Diagnosis - clinical history and physical examination.
CT often shows nonspecific colonic wall thickening and pericolic fat stranding.
Sigmoidoscopy is relatively contraindicated
Majority can be treated medically 80%
Bowel rest and broad-spectrum antibiotics are the mainstay of therapy,
Colonoscopy should be performed after recovery
Failure to improve after 2 to 3 days of medical management, progression of
symptoms, or deterioration -> surgical exploration
Primary anastomosis should be avoided


Slide 86

Pseudomembranous Colitis
(Clostridium difficile Colitis)
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Extremely common, leading cause of nosocomially acquired diarrhea
Result from overgrowth
Almost any antibiotic, even a single dose
Immunosuppression, medical comorbidities, prolonged
hospitalization or nursing home residence, and bowel surgery
increase the risk.
Two toxins: toxin A (an enterotoxin) and toxin B (a cytotoxin)
Management : immediate cessation of the offending antimicrobial
agent. Patients with mild disease10-day course of oral
metronidazole.
Severe diarrhea associated fever and abdominal pain - bowel rest,
IV hydration, and oral metronidazole or vancomycin
Fulminant colitis -> emergent laparotomy, total abdominal
colectomy with end ileostomy


Slide 87

Anorectal Diseases


Slide 88

Hemorrhoids
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Cushions of submucosal tissue containing venules, arterioles, and smoothmuscle fibers
Left lateral, right anterior, and right posterior positions
Treatment is only indicated if they become symptomatic
Straining, increased abdominal pressure, and hard stools increase venous
engorgement
External hemorrhoids distal to the dentate line, thrombosis leads to
significant pain (anoderm sensate)
Internal hemorrhoids proximal to the dentate line, insensate
Prolapse or bleed, but rarely become painful
Combined internal and external hemorrhoids straddle the dentate line and
have characteristics of both internal and external hemorrhoids
Surgery required for large, symptomatic, combined hemorrhoids
Hemorrhoidectomy is often the treatment of choice
Rectal varices are best treated by lowering portal venous pressure
Surgical hemorrhoidectomy should be avoided


Slide 89

Treatment
Medical Therapy

First- and second-degree hemorrhoids - dietary fiber, stool softeners, increased fluid intake, and avoidance of
straining.

Rubber band ligation, infrared photocoagulation,

Sclerotherapy for first-, second-, and some third-degree hemorrhoids.
Excision

Thrombosed External Hemorrhoids

Elliptical excision

Operative Hemorrhoidectomy

Closed Submucosal Hemorrhoidectomy

Redundant mucosa are identified and excised using an elliptical incision starting just distal to the anal verge and
extending proximally to the anorectal ring and the apex of the hemorrhoidal plexus is then ligated

Identify the fibers of the internal sphincter and avoid them

Close with a running absorbable suture or can be left open
Stapled Hemorrhoidectomy

removes a short circumferential segment of rectal mucosa proximal to the dentate line using a circular stapler.
Complications of Hemorrhoidectomy

Urinary retention 10 to 50% of patients

Fecal impaction

Hemorrhage

Incontinence

Anal stenosis


Slide 90

Anal Fissure
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Tear in the anoderm distal to the dentate line.
Trauma from either the passage of hard stool or prolonged diarrhea.
Causes spasm of the internal anal sphincter -> pain, increased tearing, and
decreased blood supply
Majority of anal fissures occur in the posterior midline. Ten to 15% occur in
the anterior midline.
Extremely common
Pain with defecation and hematochezia
Intense and painful anal spasm lasting for several hours after a BM
Acute fissure is a superficial tear of the distal anoderm and almost always
heals with medical management.
Chronic fissures develop ulceration and heaped-up edges with the white
fibers of the internal anal sphincter visible at the base of the ulcer, often is
an associated external skin tag and/or a hypertrophied anal papilla
internally.
Lateral location, not normal, think Crohn's disease, HIV, syphilis, etc.


Slide 91

Treatment
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Bulk agents, stool softeners, and warm sitz baths,
2% lidocaine jelly
Nitroglycerin ointment
Calcium channel blockers (diltiazem and nifedipine)
Effective in most acute fissures, but will heal only
approximately 50 to 60% of chronic fissures
Botulinum toxin
Alternative to surgical sphincterotomy for chronic fissure.
Surgical therapy traditionally has been recommended for
chronic fissures that have failed medical therapy, and
lateral internal sphincterotomy is the procedure of choice
30% of the internal sphincter fibers are divided
Healing is achieved in more than 95%


Slide 92

Anorectal Sepsis and
Cryptoglandular Abscess


Infections of the anal glands (cryptoglandular infection) found in the
intersphincteric plane.


These glands traverse the internal sphincter and empty into the anal
crypts at the level of the dentate line.

Diagnosis
 Severe anal pain
 Palpable mass
 CT or MRI to fully delineate the anatomy of the abscess.
Treatment
 Drainage as soon as the diagnosis is established.
 Examination under anesthesia
 Antibiotics only if overlying cellulitis or if the patient is
immunocompromised, has diabetes mellitus, or has valvular heart
disease.


Slide 93

Ischiorectal Abscesses

Horseshoe abscesses require drainage of the deep postanal space and often require
counterincisions over one or both ischiorectal spaces
Intersphincteric Abscess

Intersphincteric abscesses - difficult to diagnose, few external signs

deep pain that is more internal feeling

worse with coughing or sneezing

pain limits DRE usually requires an examination under anesthesia

drain through a limited, usually posterior, internal sphincterotomy
Supralevator Abscess

uncommon

can mimic intra-abdominal conditions (high location)

DRE may reveal an indurated, bulging mass above the anorectal ring

It is essential to identify the origin - secondary to an upward extension of an
intersphincteric abscess, drain via rectum.

upward extension of an ischiorectal abscess drain through the ischiorectal fossa.

If from intra-abdominal disease primary process treatment and drainage via the most
direct route (transabdominally, rectally, or through the ischiorectal fossa).


Slide 94

Necrotizing Soft Tissue
Infection of the Perineum
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Rare, but lethal, condition
Polymicrobial and synergistic
Undrained or inadequately drained cryptoglandular abscess or a
urogenital infection, or post op
Immunocomprimised patients and diabetic patients are at increased
risk
Necrotic skin, bullae, or crepitus and systemic toxicity and may be
hemodynamically unstable
Prompt surgical débridement of all nonviable tissue is required,
including multiple operations
Broad-spectrum antibiotics
Colostomy with extensive resection of the sphincter or stool
contamination of wound
Mortality approximately 50%.


Slide 95

Fistula in Ano
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50% abscesses develop a persistent fistula in ano.
Originates in the infected crypt (internal opening) and tracks to the
external opening, usually the site of prior drainage.
Fistulas are cryptoglandular in origin, trauma, Crohn's disease,
malignancy, radiation, or unusual infections (tuberculosis,
actinomycosis, and chlamydia) = complex, recurrent, or nonhealing
fistula.
Persistent drainage from openings. Indurated tract often palpable.
Goodsall's rule - guide in determining the location of the internal
opening
External opening anteriorly connect to the internal opening by a
short, radial tract.
External opening posteriorly track in a curvilinear fashion to the
posterior midline
Exceptions -anterior external opening is greater than 3 cm from the
anal margin, usually track to the posterior midline.


Slide 96


Slide 97

Treatment
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The goal of treatment of fistula in ano is eradication of sepsis
without sacrificing continence.
Encircle variable amounts of the sphincter complex
Internal opening can be ID'd with hydrogen peroxide or dilute
methylene blue
Simple intersphincteric fistulas often can be treated by fistulotomy,
curettage, and healing by secondary intention
Fistulas that include less than 30% of the sphincter muscles often
can be treated by sphincterotomy
High transsphincteric and suprasphincteric fistulas, which encircle a
greater amount of muscle, are more safely treated by initial
placement of a seton
Higher fistulas may be treated by an endorectal advancement flap
Fibrin glue and a variety of collagen-based plugs
All fistulas resulting from radiation should be biopsied to rule out
cancer


Slide 98

Human Papillomavirus
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HPV causes condyloma acuminata (anogenital warts)
and is associated with AIN and squamous cell carcinoma
(see Anal Canal and Perianal Tumors above).
HPV types 16 and 18, predispose to malignancy and
often cause flat dysplasia in skin unaffected by warts
Small warts on the perianal skin and distal anal canal
may be treated in the office with topical application of
bichloracetic acid or podophyllin. Although 60 to 80% of
patients will respond to these agents, recurrence and
reinfection are common
Larger and/or more numerous warts require excision
and/or fulguration in the operating room. Excised warts
should be sent for pathologic examination to rule out
dysplasia or malignancy


Slide 99

Trauma
Penetrating Colorectal Injury
 Trauma surgeons are increasingly performing primary repairs in
selected patients
 Contraindications to primary repair include shock, injury to more
than two other organs, mesenteric vascular damage, and extensive
fecal contamination
 Majority of penetrating rectal injuries should be treated with
proximal fecal diversion and copious irrigation of the rectum
 Intractable rectal bleeding may require angiographic embolization
Blunt Colorectal Injury
 Less common than penetrating injury. Management of these injuries
should follow the same principles
 A serosal hematoma alone does not mandate resection
 Crush injuries, require débridement of all nonviable tissue, proximal
fecal diversion, and a distal rectal washout, with or without drain
placement.


Slide 100

Anal Sphincter Injury
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Obstetric trauma>> hemorrhoidectomy, sphincterotomy,
abscess drainage, or fistulotomy. Patients with
incontinence and a suspected sphincter injury can be
evaluated with anal manometry, EMG, and endoanal
ultrasound.
Mild- may respond to dietary changes and/or
biofeedback.
Isolated sphincter injury -> repair primarily.
Rectal injury accompanied by sphincter injury -> fecal
diversion, distal rectal washout, and drain placement.
Most common method of repair of the anal sphincter is a
wrap-around sphincteroplasty


Slide 101

Human Immunodeficiency Virus

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Diarrhea, in particular, is extremely common.
Opportunistic infections with bacteria (Salmonella, Shigella, Campylobacter,
Chlamydia, and Mycobacterium species), fungi (Histoplasmosis, Coccidiosis,
Cryptococcus), protozoa (Toxoplasmosis, Cryptosporidiosis, Isosporiasis),
and viruses (CMV, herpes simplex virus) can cause diarrhea, abdominal
pain, and weight loss.
CMV in particular may cause severe enterocolitis and is the most
common infectious cause of emergency laparotomy in AIDS patients.
C. difficile colitis is a major concern in these patients, especially because
many patients are maintained on suppressive antibiotic therapy.
The incidence of GI malignancy also is increased in patients with HIV
infection. Kaposi's sarcoma is the most common malignancy in AIDS
patients and can affect any part of the GI tract.




asymptomatic or may develop bleeding or obstruction.

GI lymphoma (usually non-Hodgkin's lymphoma) also is common


Slide 102