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Flashcards in colon, rectum, anus Deck (201):
1

parts of the large intestine

-cecum is largest part and where small bowel joins colon (no distinct division between cecum and ascending colon which is retroperitoneal)
-hepatic flexure (inf to liver) bend in asc colon where it becomes transverse colon
-transverse colon suspends freely in peritoneal cavity by transverse mesocolon
-splenic flexure is where transverse colon bends at the spleen and is retroperitoneal
-descending colon is retorter down to sigmoid colon which is loop of redundant colon in llq
-distal colon is intraperi becomes the rectum at the sacrum then cont. to anal sphincters that form short (3cm) anal canal

2

rectum anatomy

-15cm long
-teniae coli disperse and disappear at level of sacral promontory resulting in longitudinal muscle layer that becomes continuous homogeneous layer
-prox rectum covered by peritoneum ant not post to 10cm above anal verge

3

importance of knowing what part of the rectum is intraperitoneal

full thickness rectal bx taken from higher than 8-9cm above anal verge carries risk of free perf into peritoneal cavity

4

where does the anal canal extend from

anorectal junction (dentate/pectinate line) to anal verge

5

what does the dentate one mark

junction between columnar rectal epithelium (insensate) and the squamous anal epithelium (richly innervated by somatic sensory nerves)

6

columns of Morgagni (rectal columns)

-immediately proximal to dentate line
-where perianal glands discharge secretions, level of anal crypts

7

where do perirectal abscesses usually originate

columns of morgagni (anal crypts)

8

what is the blood supply of ascending colon and prox half of transverse colon

branches of sma

9

what is the blood supply of distal half of transverse colon, descending colon, and sigmoid colon

infer mesenteric artery

10

importance of understanding arterial blood supply in certain areas of colon

-junction of two separate blood vessel systems, blood supply is poor so anastomoses in this region would carry higher risk of ischemic complications

11

marginal artery of drummond

vessel runs parallel to about 2-3cm from descending colon wall and is a collateral that connects the middle colic and left colic systems
-provides adequate blood supply to descending colon even if left colic artery has to be sacrificed during sigmoid or distal descending colon surgery

12

venous drainage of large bowel

- most branches accompany the arteries and eventually drain into portal system
-inf mesenteric vein drains into splenic vein which joins w super mesenteric vein to form portal vein

13

arterial supply of rectum

branch of inf mesenteric artery (sup hemorrhoidal artery) for upper rectum and from branches of internal iliac arteries (middle hemorrhoidal arteries) and internal pudendal arteries (inf hem arteries) for the middle and lower rectum

14

venous supply of rectum

veins from upper rectum drain into portal system through inf mes vein; middle and inf rectal veins drain into systemic circulation through the internal iliac and pudendal veings

15

what are hemorrhoids

physiologic venous cushions that connect the two systems

16

lymphatic drainage of large intestine

parallels arterial blood supply w several levels of lymph nodes between periaortic plexus and parabolic lymph nodes

17

order of tumor metastases of lymph nodes

paracolic lymph nodes then middle tier of lymph nodes then periaortic lymph nodes

18

layers of bowel wall of colon

mucosa, submucosa, muscularis and serosa

19

what is the major histologic difference between colon and small intestine

-colon has no villi
-outer longitudinal smooth muscle layer is separated into 3 bands (teniae coli) that cause out pouching of bowel between teniae (haustra)

20

internal sphincter

continuation of the circular muscular layer of the rectum; invol sphincter made of smooth muscle

21

external sphincter

-striated voluntary muscle
-3 parts: subq, superficial and deep portions
-deep portion is continuity w legator ani muscles (base of pelvic floor)

22

most important control of colon activity

mediated by regional reflex activity that occurs in submucosal plexuses

23

3 ways colon and rectum play role in maintaining hemeostasis

1. absorb water and electrolytes from liquid stool
2. through fermentation, help digest some starches and protein that are resistant to digestion and absorption by small bowel
3. serve as storage for feces

24

mc anaerobic colonic organism

bacteroides fragilis

25

mc aerobic colonic organisms

e coli and enterococci

26

function of colonic bacteria

-degradation of bile pigments
-production of vitamin k
-fermentation of undigested starches and proteins
-produce short chain fatty acids that are absorbed by the colon

27

does a resection of entire colon and rectum impact a person's capacity to maintain normal nutrition

no

28

what many L of chyme does the small bowel deliver to the cecum each day

1-2L

most is absorbed in ascending and transverse colon leaving

29

what does the colon absorb and secret

absorbs sodium and chloride
secretes bicarb and potassium

30

what regulates the final evacuation of solid stool

anorectum

31

how many ml/day of colonic gas does bacterial fermentation produce

800-900mL/day

32

what gives colonic gas its odor

indole and skatole

33

dx evaluation of colon and rectum

-DRE
-rigid sigmoidoscopy which been replaced by fiberoptic flexible sigmoidoscopy
-fiberoptic colonoscopy (most accurate)
-abd series (flat plate and upright radiograph)
-barium enema
-virtual colonoscopy or ct colography
-technetium labeled rbi scanning
-angiography

34

what should a sigmoidoscopy be performed

pts >50yr and performed every 3-5yrs

35

double contrast barium enema

using air insufflation while some intraluminal barium remains in the colon is particularly sensitive in detecting polyps and small lesions

36

what is a barium enema helpful in dx

tumors
diverticulosis
volvulus
obstruction

37

what is technetium labeled rbc scanning used

eval of lower gi bleeding (less rapid and pt stable)

38

what is angiography useful for

moderate or rapid colonic bleeding

39

what is a colostomy

surgical procedure in which the colon is divided and the proximal end is brought through a surgically created defect in abd wall and distal end is either overseen and placed in peritoneal vanity as a blind limb (Hartmann's procedure) or brought out inferiorly to colostomy through abd wall as mucous fistula

40

what is the purpose of a colostomy

divert stool from a diseased segment distally in the colon or rectum or to protect a distal anastomosis

41

how is a loop colostomy created

bringing a loop of colon through a defect in abd wall, placing a rod underneath, and making a small hole in the loop to allow stool to exit into colostomy bag

42

what is an ileostomy

similar to colostomy in which the ileum is brought through the abd wall to divert its contents from distal ds or in proctocolectomy, to serve as permanent stoma

43

why are stomas created

(1) to allow healing from a distal anastomosis before bowel continuity is restored; (2) the ends of the bowel are not suitable for an immediate anastomosis after resection (e.g., severely inflamed bowel, questionable vascular supply); (3) when the conditions are not right for proceeding (e.g., severe fecal peritonitis, patient too unstable or too sick to tolerate the procedure); and (4) when there is not enough bowel left for reanastomosis (abdominoperineal resection [APR]).


44

proctocolectomy

operative removal of entire colon and rectum (ulcerative colitis or polyposis syndromes)

45

abdominoperineal resection

surgical tx of very low rectal cancers; removal of lower sigmoid colon and entire rectum and anus leaving a permanent proximal sigmoid colostomy

46

low anterior resection

tx cancers of middle and upper sections of rectum; removal of distal sigmoid colon and apporx one half of rectum w primary anastomosis of prox sigmoid to distal rectum

47

what are the white lines of toldt

lateral peritoneal reflections of the ascending and descending colon

48

what parts of gi tract do not have serosa

esophagus, middle and distal rectum

49

major differences between colon and small bowel

colon has taeniae coli, haustra, and appendices epiploicae (fat appendages) whereas the small intestine is smooth

50

blood supply of proximal rectum and venous drainage

superior hemorrhoidal (superior rectal) from IMA

imv to splenic vein then to portal vein

51

blood supply of middle rectum

middle hemorrhoidal (midde rectal) from hypogastric (internal iliac)

iliac vein to ivc

52

blood supply of distal rectum

inf hemorrhoidal (inf rectal) from pudendal artery (branch of hypogastric artery)

iliac vein to ivc

53

what is the mc gi cancer

colorectal carcinoma

54

risk factors for colorectal carcinoma

diet- low fiber, high fat
genetic- famhx, FAP, lynch syndrome
IBD- UC > crohns, age, prev colon cancer

55

what is lynch's syndrome

HNPCC= Hereditary NonPolyposis Colon Cancer

autosomal dominant inheritance of high risk for dev of colon cancer

56

ACS recommendations for polyp/colorectal screening in asymp pts without 1st degree fam hx of colorectal cancer

starting age 50:
- colonoscopy q 10yrs
-double contrast barium enema (DCBE) q 5yrs
-flex sigmoidoscopy q 5yrs
-Ct colonography q5yrs

57

ACS recommendations for polyp/colorectal screening in asymp pts with 1st degree fam hx of colorectal cancer

colonoscopy at age 40 or 10 years before age at dx of youngest 1st deg relative and every 5 yrs thereafter

58

s/sx assoc w right sided lesions

r side of bowel has lg luminal diameter so tumor may attain a lg size before causing problems

microcytic anemia, occult/melena more than hematochezia PR, postprandial discomfort, fatigue

59

s/sx assoc w left sided lesions

left side fo bowel small lumen and semisolid contents

change in bowel habits (small caliber stools), colicky pain, signs of obstruction, abd mass, +heme, or gross red blood

n,v,constipation

60

from which site is melena more common

right sided colon cancer

61

which site is hematochezia more common

left sided colon cancer

62

s/sx of rectal cancer

mc is hematochezia or mucus

tenesmus, feeling of incomplete evacuation of stool, rectal mass

63

dx tests for colorectal cancer

hx/pe
heme occult
cbc
barium enema
colonoscopy

64

what ds does microcytic anemia signify until proven otherwise in man or postmenopausal woman

colon cancer

65

preop w/u for colorectal cancer

hx
pe
lfts
cea
cbc
chem 10
pt/ptt
type/cross 2u
prbcs
cxr
ua
abdominopelvic ct

66

means by which cancer spreads

direct extension-circumferentially and through bowel wall to later invade other abdominoperineal organs

hematogenous- portal circulation to liver; lumbar/vertebral veins to lungs

lymphogenous-regional lymph nodes

transperitoneal

intraluminal

67

what unique dx test is helpful in pts w rectal cancer

endorectal US

68

tnm stages

stage1- invades submucosa or muscularis propria (T1-2 N0 M0)

stage2- invades through muscularis propria or surrounding structures but w negative nodes (t3-4, N0, M0)

stage3- positive nodes, no distant metastasis (any T, N1-3, M0)

stage4- positive distant metastasis (any T, any N, M1)

69

preop bowel prep

1.golytely colonic lavage or fleets phospho-soda until clear effluent per rectum

2. PO abx (1g neomycin and 1g erythromycin x3doses)

pt should also receive preop and 24hr IV abx

70

common preop IV abx

cefoxitin (mefoxin), carbapenem

if alx- IV cipro and flagyl (metronidazole)

71

what determines low ant resection (LAR) vs abd perineal resection (APR)

distance from anal verge, pelvis size

72

what do all rectal cancer operations include

total mesorectal excision- remove rectal mesentery, including lymph nodes

73

what surgical margins are needed for colon cancer

traditionally >5cm; margins must be at least 2cm

74

how many lymph nodes should be resected w colon cancer mass

12min= for stage and may improve prognosis

75

adjuvant tx stage 3 colon cancer

5fu and leucovorin chemo

76

adjuvant tx for t3-4 rectal cancer

preop radiation therapy and 5fu chemo

77

mc site distant metastasis from colorectal cancer

liver

78

surveillance regimen of colorectal cancer

pe
stool guaiac
cbc
cea
lfts- every 3m for 3y then every 6m for 2y
cxr every 6m for 2yr then yearly
colonoscopy at yrs 1 and 3 postop
ct scans directed by exam

79

mc causes of colonic obstruction in adult population

colon cancer
diverticular ds
colonic volvulus

80

what are colonic and rectal polps

tissue growth into bowel lumen usually consisting of mucosa, submucosa or both

81

how are colonic and rectal polyps anatomically classified

sessile=flat
pedunculated= on a stalk

82

histologic classifications of inflammatory (pseudopolyp) colonic/rectal polyps

crohns or ulcerative colitis

83

histologic classifications of hamartomatous colonic/rectal polyps

normal tissue in abn configuration

84

histologic classifications of hyperplastic colonic/rectal polyps

benign-normal cells, no malignant potential

85

histologic classifications of neoplastic colonic/rectal polyps

proliferation of undifferentiated cells; premalignant or malignant cells

86

subtypes of neoplastic polyps

tubular adenomas (pedunculated)
tubulovillous adenomas
villous adenomas (sessile and look like broccoli heads)

87

what determines malignant potential of an adenomatous polyp

size
histologic type
atypia of cells

88

mc type of adenomatous polyp

tubular

89

correlation between size and malignancy of polyps

polyps larger than 2cm higher risk

90

what about histology and cancer potential of an adenomatous polyp

villous > tubovillous > tubular

villous=villain

91

where are most polyps found

rectosigmoid

92

s/sx of polyp

bleeding
change in bowel habits
mucus per rectum
electrolyte loss
totally asyptomatic

93

dx tests for polyps

colonoscopy*

barium enema and sigmoidoscopy

94

tx polyp

endoscopic resection (snared)

(if lg sessile villous adenomas - removed w bowel resection and lymph node resection)

95

familial polyposis (familial adenomatous polyposis=FAP)

hundreds of adenomatous polyps within the rectum and colon that begin developing at puberty

untx develop cancer by ages 40-50

96

inheritance pattern of FAP and genetic defect

autosomal dominant

adenomatous polyposis coli= APC gene

97

tx FAP

total proctocolectomy and ileostomy

total colectomy and rectal mucosal removal (musosal proctectomy) and ileoanal anastomosis

98

what other tumor must be looked for with FAP

duodenal tumors

99

Gardner's syndrome

neoplastic polyps of small bowel and colon

cancer by age 40 if undx

100

assoc findings of gardners syndrome

desmoid tumors (abd wall or cavity)
osteomas of skull
sebaceous cysts
adrenal and thyroid tumors
retroperitoneal fibrosis
duodenal and periampullary tumors

101

what is a desmoid tumor

tumor of musculoaponeurotic sheath, usually of abd wall

benign but grows locally

tx w wide resection

102

what meds can slow growth of desmoid tumor

tamoxifen, sulindac, steroids

103

what is peutz jeghers syndrome

hamartomas throughout the GI tract (jejunum/ileum >colon > stomach)

assoc w ovarian cancer

auto dom

104

s/sx and tx peutz jeghers syndrome

melanotic pigmentation (black/brown) of buccal mucosa, lips, digits, palms, feet

Peutz=pigmented

removal of polyps if symp or large (>1.5cm)

105

what are juvenile polyps

benign hamartomas in small bowel and colon, not premalig

"retention polyps"

106

Cronkhite Canada syndrome

diffuse GI hamartoma polyps assoc w malabsorption/wl, diarrhea, and loss of electrolytes/protein

signs- alopecia, nail atrophy, skin pigmentation

107

turcot's syndrome

colon polyps w malignant CNS tumors

108

tx diverticulitis

acute- admit to hospital, IV hydration, NPO, IV abx for 5-7d

recurrent- sigmoid colectomy

109

operation w diverticular ds w acute perf or obstruction

segment resected, diverting colostomy brought to abd wall and distal rectal stump oversewn (Hartmann)

then colostomy takedown and anastomosis to rectal stump (3months)

110

tx for colovesical fistula

surgery- primary closure of bladder and resection of sigmoid colon w primary anastomosis

111

what is considered massive bleeding related to diverticular bleeding

bleeding that is sufficient to warrant transfusion of more than 4units of blood in 24hr to maintain normal hemodynamics

rapid colonic bleeding= rate of 0.5mL/min

112

dx procedure of choice to rule out lower GI sources of bleeding

colonoscopy

113

tx diverticular bleeding

most stop on own

id of site allows surgical resection of colon

vasopressin through angiography (temporary)

coil emobolization (temp)

114

what is ulcerative colitis

IBD that involves mucosa and submucosa of large bowel and rectum

ages 15-30 then >55

115

what is crohns ds

transmural ds that can involve any portion of the alimentary canal

116

UC vs crohns

crohns- rectal sparing, skip lesions, aphthous sores, linear ulcers, thickening, strictures, string sign,fibrosis

UC-diarrhea severe, bloody, rectum/terminal ileum, continuous, friable, exudates, lead pipe, foreshortening, crypt abscesses

117

what leads to pseudo polyp formation assoc w UC

coalescing of crypt abscess (Lieberkuhn) and erosion of mucosa

118

s/sx UC

watery diarrhea that contains blood, pus and mucus

cramping

abd pain

tenesmus

urgency

varying- wl, dehydration, pain, fever

119

dx UC

endoscopy w bx- friable, reddish mucosa w no normal intervening areas, mucosal exudates, and pseudopolyposis

barium enema

shortening of colon, loss of normal austral markings and lead pipe appearance

120

tx UC and crohns

initial is medical therapy- antidiarrheal agents (loperamide) and bulking agents (psyllium)

moderate- sulfasalazine or mesalamine

severe- steroid

crohns- infliximab (remicade)

uc- surgery, total colectomy w proctectomy and ileoanal pull through

121

mc site of colonic obstruction

sigmoid colon

122

mc causes of colonic obstruction

adenocarcinoma

scarring assoc w diverticulitis

volvulus

123

s/sx colonic obstruction

abd distension, cramping abd pain, n, v, obstipation

pe- abd distention, tympany, high pitched metallic rushes, gurgles, localized tender palpable mass ( indicates strangulated closed loop or diverticular ds)

124

radiologic and ct findings colonic obstruction

proximal colon, air fluid levels, no distal rectal air

125

dx colonic obstruction

axr

water soluble contrast enema

barium enema

colonoscopic esp w Ogilvie's syndrome (localized paralytic ileus of colon without mechanical obstruction)

126

why should barium never be given orally w colonic obstruction

accumulates proximal to the obstruction and cause a barium impaction

127

tx large bowel obstruction

IV fluids,NG suction, continuous observation

emergency lap for acute w cecal distention >12cm, severe tenderness, evidence of peritonitis, generalized sepsis

perf from volvulus/cancers/diver-lap w resection and diverting colostomy

cancer wout peritonitis-colonic stent placement allows decompression

Ogilvie's- IV neostigmine

128

complications of lg bowel obstruction

perforation, peritonitis, sepsis

129

what is a volvulus

rotation of a segment of the intestine on axis formed by mesentery

stretching and elongation w age

hypermobile cecum

130

mc site of volvulus lg bowel

sigmoid and cecum

131

s/sx volvulus

abd distention, v, abd pain, obstipation, tachypnea

pe-distention, tympany, high pitched tinkling sounds, rushes

132

dx volvulus

axr

water soluble contrast enema- funnel narrowing resembles birds beak or ace of spades

ct scan

133

tx volvulus

sigmoidoscopy w rectal tube insertion to decompress sigmoid volvulus

cecal volvulus- cecopexy (suturing the cecum to parietal peritoneum) or w right hemicolectomy w ileotransverse colostomy

134

tx tubular polyp

endoscopic excision

135

tx villous polyp

surgical removal

136

tx of hamartoma polyp

excise for bleeding or obstruction

137

tx inflammatory polyp

observation

138

tx hyperplastic polyp

observation

139

where do most large bowel cancers occur

lower left side of colon near rectum

140

mild risk factors for colorectal cancer

age
diet
physical inactivity
obesity
smoking
race
alcohol

141

screening guidelines for polyps and cancer

1. flex sigmoid every 5yr
2. colonoscopy ever 10yr
3. double contrast barium enema every 5yr
4. ct colonography every 5 yr

all start at age 50 unless fhx or higher risk then age 40 or 10yr before person with cancer age

higher risk also do every 3-5yr instead of 10yr

142

symptoms assoc w cancer of right colon

-exophytic lesions
-occult blood loss=fe def anemia
-weight loss
-mass
-virchows node
-blunder's shelf

143

symptoms assoc w cancer of left colon

-+/- weight loss
-rectal bleeding
-blunder's shelf
-obstruction

144

symptoms assoc w cancer of rectum

-rectal bleeding
-tympany
-obstruction
+/- alt diarrhea/constipation

145

tx for colorectal cancer

resection including lymph nodes

146

mc organ involved in distant colorectal metastases

liver

147

how are tumors of cecum and ascending colon tx

right hemicolectomy that includes resection of distal portion of ileum and colon to mid transverse colon with an ileo mid transverse colon anastomosis

148

tx cancers to right and left middle colic artery

right- extended right hemicolectomy

left-partial left colectomy

149

tx hepatic flexure lesions

extended right colectomy that includes resection to or beyond level ofmidtransverse colon

150

tx splenic flexure and left sided lesions

left hemicolectomy thats includes resection from level of mid transverse colon to sigmoid

151

tx sigmoid colon lesions

sigmoid resection

152

tx obstructing or perf tumors

resection, diverting colostomy, and hartmann's pouch or mucous fistula

153

what is folfox and what is it used for

-5fu, leucovorin, oxaliplatin

-tx metastatic colorectal cancer

154

tx rectal tumors

resection + radiation + 5fu

155

what is used to stage the depth of penetration of the tumor in the rectal wall

endorectal us or mri

156

TNM staging

tx= primary tumor not assessed
to= no evidence prim tumor
tis= carcinome in situ; intraepithelial tumor or invasion of lamina propria
t1= submucosa
t2= muscularis propria
t3= muscularis propria into subserosa or into nonperitonealized pericolic or perirectal tissues
t4= organs or structures or perf visceral peritoneum

nx= nodes not assessed
no=no regional nodes
n1= 1-3 pericolic or perirectal nodes
n2=>4 pericolic or perirectal nodes
n3= any node along course of vascular trunk or to >1 apical node

mx= no distant metastasis assessed
mo= no distant metastasis
m1= distant metastasis

157

frequent follow up visits

3m for 2 yrs then 6m for 3 yrs then yearly until 10yr post resection

colonoscoy 1-2 yr postop then every 2-3yr

158

when do most recurrences happen

18-24 months

159

what is the most sensitive test to detect widespread metastases in colorectal cancer

positron emission tomography (PET)

160

rectal prolapse

intussessception of a full thickness portion of rectum through the anal opening

161

mucosal prolapse

eversion of 2-3cm of rectal mucosa through anal opening but which is not full thickness

162

difference between rectal prolapse and mucosal/hemorrhoidal prolapse

rectal has concentric, circumferential mucosal folds where mucosal has radial pattern of folds

163

rectal pain/pressure with mild bleeding, incontinence, mucous discharge and wet anus

rectal prolapse

164

tx rectal prolapse

intra abdominal procedure including sigmoid resection (redundant bowel) w rectopexy (suturing the bowel wall to the pre sacral fascia to immobilize it)

165

tx mucosal or hemorrhoidal prolapse

three column hemorrhoidectomy

166

what are the 3 positions in which hemorrhoids are normally found

left lateral

right anterior

right posterior

167

location of internal vs external hemorrhoids

internal- originate above dentate line

ext- below dentate line

168

degree of internal hemorrhoidal prolapse

1st- int hem do not prolapse

2nd- int hem prolapse w defecation and return spont. to anatomic position

3rd- int hem prolapse w defecation and require manual reduction

4th- not reducible

169

what is recommended in tx of hemorrhoids

bulk forming agents (psyllium derivatives) and avoidance of constipation

170

1st degree int hem def and tx

-bulge in anal canal lumen; doesn't protrude outside of lumen

-asym= bulking agents, no constipation, inc water intake

-symp= same asym, rubber band ligation, infrared coag

171

2nd degree int hem def and tx

- protrudes w defecation reduces spont

-conservative man or rubber band ligation

172

3rd degree int hem def and tx

- selected cases= rubber band ligation

-mixed= surgical hemorrhoidectomy

173

4th degree int hem def and tx

-protrudes, permanently incarcerated

-surgical hemorrhoidectomy

174

how long do thromboses ext hem last

self limited and resolves progressively over 7-10d

175

how are most anorectal abscesses start

obstruction of the perianal glands located between internal and external sphincters; as it inc in size and spreads it becomes a perianal abscess

176

what are the mc perirectal abscesses

perianal and ischiorectal

177

tx of rectal abscess

drainage

178

after drainage of a perirectal abscess what does a pt have a 50% chance of having

chronic fistula-in-anu- abnorm communication between anus at level of dentate line and perirectal skin through the bed of previous abscess

179

intersphincteric fistulae is result of

perianal abscess

180

transsphincteric fistulae is result of

ischiorectal abscess

181

supresphincteric fistulae result of

suprelevator abscess

182

chronic drainage of pus and sometimes stool from the skin opening

fistula

183

Goodsall's rule

imaginary line drawn from right lateral to left lateral position at level of anus

184

tx of fistula

fistulotomomy- unroofing the fistula tract, allowing to heal slowly by secondary intention

185

mc cause of severe localized anorectal pain

anal fissure- linear tears in lining of anal canal below level of dentate line

186

where do most anal fissures occur

posteroanterior plane because pelvic muscular support is weakest along axis

187

classic triad assoc w anal fissures

-ext skin tag
-fissure exposing internal sphincter fibers
-hypertrophied anal papilla at level of dentate line

188

tx anal fissures

-acute= conservative tx, avoid d/c, bulk laxatives, mild nonnarcotic analgesic; sits baths; topical agents (procainamide, nitroglycerin) relax sphincter

-fails or is chronic=surgery= partial lateral internal sphincterotomy

189

two types of anal cancers

-epidermoid carcinoma (generic type includes squamous cells, basaloid, cloacogenic, mucoepidermoid, transitional carcinomas)

-malignant melanoma

190

tx anal cancers

chemo and radiation using protocol of pelvic radiation w infusion of 5fu and mitomycin c

191

mc anorectal infx affecting homosexual men

anal condylomas- pink/white papillary lesions, cauliflower like, bleed easily, pain

192

tx anal condylomas

-topical= bichloracetic acid, poco-phyllin

-local destructive= electrocoag, cryo, laser

193

rectal symptoms including tenesmus and pain, hematochezia, ulcer

chlamydia- friable, ulcerating erythematous mucosa

194

tx chlyamydia

tetracycline or doxycycline

195

pruritus, tenesmus, hematochezia w thick yellow mucopurulent discharge

neisseria gonorrhea

196

tx n gonorrhea

ceftriaxone w tx for chlamydia (tetra or doxy)

197

A 57-year-old man comes to clinic with complaints of foul-smelling urine and two urinary tract infections treated with antibiotics by his primary care physician over the past 6 weeks. He has no pain at this time. Two months ago, he was seen in the emergency department with 2 days of left lower quadrant pain and constipation and was treated with oral antibiotics for diverticulitis. His past history is otherwise negative. His only medication Is ciprofloxacin. He is afebrile and vital signs are normal. A urine sample is cloudy with sediment. What is the next best step In diagnosis?

CT scan remains the most sensitive test for diagnosis of enterovesical fistula and location of the portion of the intestinal tract involved. Plain radiographs may show air in the bladder, but not the etiology. Ultrasound has no role. Barium enema Identifies the fistula

198

A 62-year-old woman is seen in the emergency department with dark red rectal bleeding and hypotension. Initial hemoglobin is 7.2. She is given intravenous fluids and two units of packed red blood cells but continues to have large amounts of bloody stools. Nasogastric tube effluent is clear bilious fluid. The best choice for Identification of the bleeding site at this time is .

mesenteric angiography

While rigid proctoscopy may be done, it Is unlikely to identify a source of massive bleeding. The patient is unlikely to be sufficiently stable for the colonoscopy prep or the time required for it. Tagged RBC scan Is more sensitive than angiography for Identifying active bleeding, but much less specific for identifying the source of bleeding and is not as useful in massive bleeds. Diagnostic laparoscopy would not elucidate the bleeding source. Mesenteric angiography Is much more specific for identifying the source and offers the potential for therapy (angiographic embolization) to control bleeding as well in selected cases.

199

An 85-year-old male nursing home resident is brought to the emergency department with 3 days of painless abdominal distention and obstipation. He appears to be in no pain, but his abdomen is massively distended and tympanitic. Plain abdominal films show a kidney-bean-shaped air-filled structure suspicious for cecal volvulus. The best management at this point is .

right colon resection

Observation occurs In Ogllvle’s, not volvulus. Contrast enema decompression Is not useful in cecal volvulus. Colonoscopic detorsión is useful for sigmoid volvulus, but considered unwise in cecal volvulus due to associated risks. Cecopexy carries a high rate of revolvulus.

200

A 41 -year-old man Is seen In clinic with bright red rectal bleeding, seen on the toilet tissue intermittently over the last several months. He is an insurance agent, exercises regularly, and eats a well-balanced diet. He denies changes In bowel habits. Family history is unremarkable. His vital signs are normal. His abdomen exam is normal. Digital rectal exam is normal, and blood is Identified on the examining finger. Anoscopy shows no other pathology. What is the next best step in diagnosis?

colonoscopy

In the absence of an obvious source in the anus or distal rectum, further evaluation of the colon Is needed. Fecal occult blood test (FOBT) Is irrelevant with a history of visible rectal bleeding. CBC is unlikely to be helpful. Flexible sigmoidoscopy only examines part of the colon. While barium enema may Identify an abnormality anywhere In the colon, It Is not as specific as colonoscopy.

201

A 24-year-old woman is seen In clinic with anal pain. Examination shows a fissure in the anterior midline of the anal canal. Digital rectal exam cannot be performed due to pain. The next step in management should be .

sitz baths, bulking agents, reassurance

The presentation is classic for traumatic anal fissure. Fissures off the midline generally prompt evaluation for other etiologies.