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CHAPTER 30
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The Appendix
1. A 25-year-old man presents with migratory right lower
quadrant (RLQ) pain, leukocytosis, and a computed
tomography (CT) scan consistent with acute, uncomplicated appendicitis. He is physiologically normal and it is
2 AM. You are planning an appendectomy, what difference might be expected in his outcome if his operation is
delayed until the next morning?
A. Increased risk of an intra-abdominal abscess
B. Increased risk of surgical-site infection
C. Decreased operative time
D. Increased risk of perforation
E. No difference in perforation rates, surgical-site
infection, abscess, conversion rate, or operative time
2. A 55-year-old man has computed tomography (CT)
evidence of complicated appendicitis with a contained
abscess in the right lower quadrant (RLQ). He is mildly
tachycardic, afebrile, and normotensive with local RLQ
tenderness but no peritonitis. What is the optimal
approach to this patient?
A. Immediate laparotomy
B. Laparoscopic exploration and abscess drainage
C. Percutaneous drainage, intravenous (IV) fluids,
bowel rest, and broad spectrum antibiotics
D. IV fluids, bowel rest, and broad spectrum antibiotics
Answer: E
Emergent surgery is often performed in patients with appendicitis, but studies have evaluated the performance of urgent
surgery (waiting < 12 hours) in a semi-elective setting after
administering antibiotics upon admission. The studies did
not reveal any significant difference in outcomes, except for a
slightly longer hospital stay in those undergoing urgent surgery. Currently, delaying surgery <12 hours is acceptable in
patients with short duration of symptoms (<48 hours) and in
nonperforated, non-gangrenous appendicitis. (See Schwartz
11th ed., p. 1335.)
Answer: C
Perforated appendicitis can be managed either operatively or
nonoperatively. Immediate surgery is necessary in patients
that appear septic, but this is usually associated with higher
complications, including abscesses and enterocutaneous
fistulae due to dense adhesions and inflammation. The management of long-duration, complicated appendicitis is often
staged. Patients are resuscitated and treated with IV antibiotics. Patients with long-standing perforation are better treated
with adequate percutaneous image-guided drainage. This
strategy is successful in 79% of patients who achieve complete
resolution, which occurs more often in lower-grade abscesses,
trans-gluteal drainage, and with CT- (vs. ultrasound-) guided
drainage. Operative intervention is performed in patients
who fail conservative management and in patients with free
intra-peritoneal perforation. (See Schwartz 11th ed., p. 1335.)
3. An 8-year-old boy presents to the emergency department complaining of generalized abdominal pain over
the past 24 hours. Laboratory tests reveal a leukocytosis
of 13,000 and he is tender in the right lower quadrant
(RLQ) on physical examination. He is taken to the operating room for laparoscopic appendectomy. Removal of
the appendix has been associated with a protective effect
to which of the following?
A. Crohn colitis
B. Ulcerative colitis
C. Clostridium difficile
D. Carcinoid
Answer: B
Previously considered a vestigial organ, the appendix is now
linked to the development and preservation of gut-associated
lymphoid tissue (GALT) and to the maintenance of intestinal
flora. It has been suggested that appendectomy is associated
with increased C. difficile infections and increased subsequent
cancer (colon, esophageal) as a result of microbial alteration,
although this is currently unproven. The protective effect of
an early appendectomy against development of ulcerative
colitis has been proposed to be mechanistically linked to the
release of dimeric forms of IgA from plasma B cells and the
Th2 response mediated by IL-13–producing natural killer T
cells. (See Schwartz 11th ed., p. 1331.)
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4. While reviewing pathology of a recent laparoscopic
appendectomy, you note that in addition to acute appendicitis, the patient had a 1.5-cm carcinoid tumor located
at the base of the appendix with mesenteric invasion.
The patient is otherwise healthy and recovering well
from surgery. What would you recommend?
A. No additional therapy is necessary.
B. Right hemicolectomy.
CHAPTER 30
C. Radical appendectomy.
D. Adjuvant chemotherapy.
The Appendix
5. A previously healthy 20-year-old man was brought to
the emergency room with a 10-hour history of fever,
anorexia, vomiting, and pain in the right lower abdomen. On examination, he has tenderness localized to
McBurney’s point. His laboratory data show leukocytosis of 13,000/mm3. On surgical exploration, you note a
normal-appearing appendix and cecum. The terminal
ileum appeared inflamed and edematous, concerning for
Crohn disease without stigmata of obstruction. What is
the most appropriate further course of action?
A. Abort the planned appendectomy.
B. Resect the inflamed terminal ileum.
C. Bypass the inflamed ileum by performing
ileo-colostomy.
D. Perform an appendectomy if the base is uninflamed.
Answer: B
Appendiceal carcinoid tumors are submucosal rubbery
masses that are detected incidentally on the appendix.
Carcinoid tumors of the appendix are relatively indolent but
can develop nodal or hepatic metastases. Infrequently, these
can be associated with carcinoid syndrome if there are hepatic
metastases (2.9%). Upon incidental findings of a suspected
carcinoid, the surgeon must evaluate the nodal basin along
the ileocolic pedicle and also examine the liver for any signs
of metastases. For lesions that are <1 cm (95% of all lesions),
a negative margin appendectomy is adequate. For tumors
≥2 cm, a right hemicolectomy is recommended. For lesions
1 to 2 cm in size, there is no consensus on a completion colectomy. A right colectomy is often performed for mesenteric
invasion, enlarged nodes, or positive or unclear margins.
Measurement of serum chromogranin A is recommended.
A radical appendectomy is not a described operation and
adjuvant chemotherapy could be considered but only after
definitive surgical care. (See Schwartz 11th ed., p. 1338.)
Answer: D
Upon performing a laparoscopy or laparotomy for suspected
appendicitis, if one finds no evidence of appendicitis, a thorough exploration of the peritoneum must be performed to
rule out contributing pathology. A normal appendix is often
removed to reduce future diagnostic dilemma. Management
of incidentally found common conditions is summarized in
Table 30-1. (See Schwartz 11th ed., p. 1337 and Table 30-3.)
TABLE 30-1 Management of Intraoperative Findings Mimicking Appendicitis
Ovarian torsion Conservative management with detorsion and oophoropexy
Crohn terminal ileitis Appendectomy if base uninflamed
Meckel diverticulitis Segmental small bowel resection and primary anastomosis
Appendiceal mass Laparoscopic appendectomy/ ileocecectomy without capsular disruption or spillage and retrieval in a bag
6. During a laparoscopic appendectomy on a 59-year-old
woman with clinical presentation of acute appendicitis,
you find an enlarged cystic mass replacing the appendix
with a normal appendiceal stump. The mass is nonadherent to the rest of the structures, and the rest of the
abdominal cavity appears normal. What is the most
appropriate next step?
A. Perform a right hemicolectomy after obtaining con-
sent from the family
B. Close the abdomen and arrange a return visit for
reevaluation
C. Laparoscopically excise the abnormal appendix with-
out capsular disruption by dividing the appendix at
the normal stump and retrieve the specimen in a bag
D. Limited ileocecectomy
Answer: C
Low-grade appendiceal mucinous neoplasms (LAMN) are
nonmalignant neoplasms of the appendix that present in a
third of cases with appendicitis. It is important to carefully
assess for the presence of ascites, peritoneal disease, and scalloping of the liver surface on imaging upon initial evaluation.
A reliable diagnosis cannot be established using imaging
alone, and it is recommended that surgical excision without
capsular disruption is undertaken. The importance of careful handling of a LAMN and the avoidance of rupture cannot
be overemphasized because the intraperitoneal spread of epithelial cells with subsequent development of pseudomyxoma
peritonei is a dreaded consequence. In cases where a homogeneous cyst without nodularity or signs of dissemination is
encountered, laparoscopic excision is acceptable, provided
that a stapler is fired across the base of the cecum to avoid a
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positive margin. The specimen should be placed in a plastic
bag and carefully removed without disruption. (See Schwartz
11th ed., p. 1339.)
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7. A 30-year-old woman presented with pain in the right
lower abdomen, fever, nausea, and leukocytosis. With
a diagnosis of appendicitis, you took her to operating
room (OR) for laparoscopic appendectomy. During the
surgery, you noticed the appendix base is perforated and
appeared nonviable (Fig. 30-1). What is the most appropriate management?
A. Place a drain and close the abdomen
B. Place an endoloop around the site of perforation and
divide the appendix
C. Resect the appendix at the site of perforation and
suture the base
D. Perform appendectomy using a stapling device, with
staple line through the healthy cecum
Answer: D
In the case of a nonviable appendix base, a staple line through
the cecum that avoids the ileocecal valve might be sufficient,
unless significant inflammation is present. The appendix
is retrieved through the midline port in a specimen bag,
especially if an appendiceal lesion is suspected. If a periappendiceal phlegmon is encountered or if the operation is
being performed for perforated appendicitis, careful sweeping
of the bowel with a blunt dissector can release the appendix. It
is important to carefully separate adjacent bowel, which can
be friable in such settings. (See Schwartz 11th ed., p. 1336.)
CHAPTER 30
The Appendix
FIG. 30-1. Gangrenous appendicitis with
perforation is seen at laparoscopy.
8. A 26-year-old man presents with a 1-day history of right
lower abdominal pain and fever. He undergoes a laparoscopic converted to open appendectomy due to difficulty
in dissecting the appendiceal stump. Intraoperatively, he
is noted to have a perforated appendix base with minimal peritoneal contamination. The appendectomy is
completed by stapling the cecum at a healthy area. What
is the most appropriate postoperative antibiotic therapy?
A. Single dose cefazolin.
B. Cefazolin and metronidazole for 3 to 4 days.
C. Piperacillin/Tazobactam for 7 to 8 days.
D. Postoperative antibiotics are not needed.
9. A 24-year-old woman presents with pain in her abdomen, fever and tenderness in right lower quadrant for the
last 8 hours. A computed tomography (CT) scan reveals
uncomplicated appendicitis. She is concerned about an
appendectomy and is afraid of surgery. She asks for alternate treatment options. What are appropriate alternate
options for this otherwise healthy patient?
A. Counsel that surgery is the only option.
B. Prescribe oral fluoroquinolones with analgesics and
ask her to follow up after a week.
C. Admit and start intravenous (IV) antibiotics.
D. Reassure her that surgery is not emergent, and she
can reconsider it after a few weeks.
Answer: B
In patients with perforated appendicitis undergoing operative
intervention, preoperative antibiotics are necessary to cover
gram-negative bacteria and anaerobes. Monotherapy with
piperacillin/tazobactam or combination of cephalosporin
with metronidazole are reasonable choices. The duration of
postoperative antibiotics is generally <4 days once complete
source control has been achieved (STOP-IT trial). Patients
with incomplete drainage, persistent catheters, complications from surgery, and uncertain resolution of inflammation
might need a longer duration of antibiotics. (See Schwartz
11th ed., p. 1336.)
Answer: C
The preferred approach to manage patients with uncomplicated appendicitis is an appendectomy. Several recent randomized trials and cohort studies have examined the role
of nonoperative management of adult patients with appendicitis. A majority of the patients in the nonoperative arm
received IV antibiotics for a short course followed by a course
of a fluoroquinolone and metronidazole, or oral amoxicillin/clavulanic acid. Currently, conservative management can
be offered to informed patients using techniques of shared
decision-making, but it is not the standard modality of management of appendicitis, except in patients with significant
phobia of surgery (Fig. 30-2). (See Schwartz 11th ed., p. 1335.)
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CHAPTER 30
The Appendix
FIG. 30-2. Coronal view of CT shows
inflammatory changes involving the appendix
without evidence of abscess, consistent with
uncomplicated acute appendicitis.
10. A 32-year-old otherwise healthy male patient presents
with suspicious symptoms of appendicitis but the physical examination is inconclusive. Which statement about
imaging in this clinical situation is correct?
A. An ultrasound is preferred to computed tomography
(CT) scan due to its higher sensitivity and reduced
risk of radiation to patients.
B. A CT finding of enlarged appendiceal lumen and
double wall thickness (>6 mm) suggests inflammatory enteritis instead of appendicitis.
C. Low dose CT scans (2 mSv) have equivalent clinical
accuracy as high dose CT scans in the diagnosis of
appendicitis.
D. Graded compression ultrasound suggestive of eas-
ily compressible appendix < 5 mm in diameter is
pathognomonic of appendicitis.
Answer: C
Imaging is often utilized to confirm a diagnosis of appendicitis because a negative operation rate is acceptable in <10%
of male patients and <20% of female patients. A contrastenhanced CT scan has a sensitivity of 0.96 (95% confidence
interval [CI] 0.95–0.97) and specificity of 0.96 (95% CI 0.93–
0.97) in diagnosing acute appendicitis. Features on a CT scan
that suggest appendicitis include enlarged lumen and double
wall thickness (>6 mm), wall thickening (>2 mm), periappendiceal fat stranding, appendiceal wall thickening, and/or
an appendicolith. While there remains a concern of ionizing
radiation exposure with a CT scan, typical low-dose CT scans
result in exposure of 2 to 4 mSv, which is not significantly
higher than background radiation (3.1 mSv). Recent trials
have also suggested that although low-dose CT scans of 2 mSv
do not generate high-resolution images, using these lower
resolution images does not affect clinical outcomes. Ultrasonography has a sensitivity of 0.85 (95% CI 0.79–0.90) and a
specificity of 0.90 (95% CI 0.83–0.95). Graded compression
ultrasonography is used to identify the anteroposterior diameter of the appendix. An easily compressible appendix <5 mm
in diameter generally rules out appendicitis. (See Schwartz
11th ed., p. 1333.)
CHAPTER 31
Diaphragm
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Liver
1. With regard to hepatic anatomy, the falciform ligament
divides the _______ from the _______:
A. caudate lobe, quadrate lobe
B. right lobe, left lobe
C. left medial section, left lateral section
D. left medial section, right lobe
Right triangular
ligament
Answer: C
The falciform ligament divides the left lateral section from
the left medial section. The plane between the gallbladder
fossa and the inferior vena cava (IVC)—referred to as Cantlie
line—divides the right and left lobes. The falciform ligament,
along with the round, triangular, and coronary ligaments
may be divided in a bloodless plane during liver resection
(Figs. 31-1 through 31-3). (See Schwartz 11th ed., Figs. 31-1
through 31-3, p. 1347.)
Left triangular
ligament
Falciform
ligament
Round
ligament
FIG. 31-1. Hepatic ligaments
suspending the liver to the diaphragm
and anterior abdominal wall.
FIG. 31-2. In situ liver hilar anatomy
with hepatoduodenal and gastrohepatic
ligaments. Foramen of Winslow is depicted.
Liver in situ
Foramen of
Winslow
Gastrohepatic
ligament
Open hepatoduodenal ligament
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Right lobe Left lobe
II
CHAPTER 31
Liver
FIG. 31-3. Couinaud’s liver
segments (I through VIII) numbered
in a clockwise manner. The left lobe
includes segments II to IV, the right
lobe includes segments V to VIII, and
the caudate lobe is segment I. IVC =
inferior vena cava.
IVa
VIII
VII
IVb
V
VI
Right lobe Left lobe
V
VI
VII
IVCCaudate lobe
III
IVb
III
I
II
2. The most common variant of normal hepatic artery
anatomy is:
A. Replaced left hepatic artery from the left gastric
ar ter y.
B. Completely replaced common hepatic artery from
the superior mesenteric artery.
C. Replaced right and left hepatic arteries.
D. Replaced right hepatic artery from the superior mes-
enteric artery.
Answer: D
Understanding the anatomic variants of the hepatic arterial supply is important to avoid complications during liver
surgery. The standard arterial anatomy is as follows: the common hepatic artery arises from the celiac trunk, and then
divides into the gastroduodenal and proper hepatic artery. In a
standard configuration, the proper hepatic artery gives rise to
the right gastric artery, but this is variable. The proper hepatic
artery then divides into the right and left hepatic artery. However, this standard arterial configuration only occurs in 76%
of patients. The most common variants include: replaced
or accessory right hepatic artery from the superior mesenteric artery (10%–15%), replaced left hepatic artery from the
left gastric artery (3%–10%), replaced right and left hepatic
arteries (1%–2%), and the completely replaced common
hepatic artery from the superior mesenteric artery (1%–2%)
(Figs. 31-4 and 31-5). (See Schwartz 11th ed., Figs. 31-4 and
31-5, p. 1349.)
LHA
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265
RHA
Hepatic artery
proper
Right gastric
artery
Common hepatic artery
Gastroduodenal artery
FIG. 31-4. Arterial anatomy of the upper abdomen and liver, including the celiac trunk and
hepatic artery branches. a. = artery; LHA = left hepatic artery; RHA = right hepatic artery.
Left gastric
artery
Celiac trunk
Splenic artery
CHAPTER 31
Liver
Replaced right hepatic
artery from SMA (10%–15%)
Replaced right and replaced left
hepatic arteries (1%–2%)
FIG. 31-5. Common hepatic artery anatomic variants. SMA = superior mesenteric artery.
3. Which of the following correctly pairs the segments of
the liver and their associated systemic venous drainage?
A. Segments I, II, III: right hepatic vein
B. Segment IV: right hepatic vein
C. Segment I: IVC
D. Segments V, VI, VII, VIII: left hepatic vein
Replaced left hepatic artery
from left gastric artery (3%–10%)
Completely replaced common
hepatic artery from SMA (1%–2%)
Answer: C
There are three hepatic veins (right, middle, and left) that
serve as the outflow for the hepatic circulation and drain
into the suprahepatic inferior vena cava (IVC). The right
hepatic vein drains segments V–VIII; the middle hepatic
vein drains segment IV, as well as segments V and VIII; and
the left hepatic vein drains segments II and III. The caudate
lobe (segment I) drains directly into the IVC (Fig. 31-6). (See
Schwartz 11th ed., Fig. 31-8, p. 1350.)
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IVC
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IVC and 3 HVs
CHAPTER 31
Liver
Posterior
segment
structures
Right HV
Anterior
segment
structures
Right lobe
Middle
hepatic
v.
Lateral
segment
structures
Left HV
Left lobe
Middle HV
Medial
segment
structures
Falciform
ligament
Hepatic a.
Portal v.
Gallbladder
FIG. 31-6. Confluence of the three hepatic veins (HVs) and the inferior vena cava (IVC). Note that the middle and left HVs drain
into a common trunk before entering the IVC. a. = artery; v. = vein. (Adapted with permission from Cameron JL: Atlas of Surgery.
Vol. I, Gallbladder and Biliary Tract, the Liver, Portasystemic Shunts, the Pancreas. Toronto: BC Decker; 1990.)
4. There is considerable variability in hepatic duct confluence anatomy, in 60%–70% of cases what is the normal
anatomy?
A. Hepatic ducts follow arterial branching inside the
liver.
B. The right anterior hepatic duct enters the liver above
the hilar plate and the posterior duct enters segment
V, lateral to the portal vein.
C. The left hepatic duct has a short extrahepatic course,
coursing with the left portal vein.
D. Hepatic ducts follow hepatic vein branching inside
the liver.
Answer: A
In general, the hepatic ducts follow the arterial branching
pattern inside the liver. The right anterior hepatic duct usually enters the liver above the hilar plate, whereas the right
posterior duct dives behind the right portal vein and can be
found on the surface of the caudate process before entering
the liver. The left hepatic duct typically has a longer extrahepatic course before giving off segmental branches behind
the left portal vein at the base of the umbilical fissure.
There is a nonstandard hepatic duct confluence with accessory or aberrant ducts (Fig. 31-7). (See Schwartz 11th ed.,
Fig. 31-9, p. 1351.)
267
ra
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A: Normal bifurcation 57%
B: Trifurcation of 3 ducts 12%
C: R anterior (C1, 16%) or R posterior
(C2, 4%) duct draining into CHD
D: R posterior (D1, 5%) or R anterior
duct (D2, 1%) draining into the left
hepatic duct
E: Absence of hepatic duct
confluence 3%
C1
5%
I
16%
IV
lh
lh
rp
rp
lh
III
ra
II
rp
rp
A57% B12%
ra
rp
C20%
ra
rp
D6%
D1
ra
rp
E3%
2%
E1
ra
rp
ra
lh
lh
CHAPTER 31
4%
C2
ra
Liver
lh
1%
D2
1%
E2
III
IV
II
I
F: Drainage of R posterior duct into
cystic duct 2%
FIG. 31-7. Main variations of hepatic duct confluence. As described by Couinaud in 1957, the bifurcation of
the hepatic ducts has a variable pattern in approximately 40% of cases. CHD = common hepatic duct; lh = left
hepatic; R = right; ra = right anterior; rp = right posterior. (Reproduced with permission from Blumgart LH, Fong Y:
Surgery of the Liver and Biliary Tract, 3rd ed, Vol. I. London: Elsevier; 2000.)
5. In a fasting state, how does the liver generate glucose?
A. Early and persistent breakdown of glycogen storage
B. Early glycogen breakdown through glycogenolysis
and later gluconeogenesis from lactate, amino acids,
and glycerol
C. Immediate gluconeogenesis from noncarbohy-
drate precursors including lactate, amino acids, and
glycerol
D. Protein catabolism through amino acid deamination
ra
rp
lh
F2%
Answer: B
The liver maintains glucose concentrations in a normal
range over both short and long periods by performing several important roles in carbohydrate metabolism. In the fasting state, the liver ensures a sufficient supply of glucose to
the central nervous system. The liver can produce glucose
by breaking down glycogen through glycogenolysis and by
de novo synthesis of glucose through gluconeogenesis from
noncarbohydrate precursors such as lactate, amino acids, and
glycerol. In the postprandial state, excess circulating glucose
is removed by glycogen synthesis or glycolysis and lipogenesis. (See Schwartz 11th ed., p. 1351.)
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