surgery ii 3.1a appendix - dr. haw

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Dr. Haw | September 1, 2014

Surgery II Surgery 3.1a Appendix3rd Year1stSe

Group 21 Gabor, Gaerlan, Galan, Galang K., Galang C., Gammad

OUTLINE

I. Acute Appendicitis

II. Acute Appendicitis in Special Populations

III. Meckel’s Diverticulum

IV. V. Appendiceal Tumors

Resources: Recording, PowerPoint, Schwartz and Sabiston (Dr. Haw got most of it

from Sabiston though)

I. ACUTE APENDICITITS

A. Epidemiology

Most commonly encountered acute surgical condition of the

abdomen.

o 1% of all operations is due to acute appendicitis

o 10/10000 patients every year

Appendicitis according to type:

o 15% -normal

o

20% - perforated

o 65% - acute

Appendicitis according to age:

o Most common during the 2nd to 4th decade of life

Mean age of 31.3 years

Median at 23 years

o

Less common among extremes of age

o But can occur at any time in your life up to the age of 90

But in the elderly, the appendiceal lumen is already

closed and scarred and so fecalith don’t obstruct it and

they rarely develop appendicitis.

Appendicitis according to gender:

o M:F ratio is 1.2:1

o Lifetime risk for Males: 8.6%

o

Lifetime risk for Females: 6.7%

Misdiagnosis

o Rate of misdiagnosis and rate of appendicle rupture is 15.3%

o Percentage of misdiagnosis is higher in females (22.9%) than

men (9.3%) respectively.

Appendectomy

o

Lifetime rate for appendectomy: 17%

o

Men: 12%

o Women: 25%

Negative Appendectomy

o The highest negative appendectomy rate among women of

reproductive age is 23.2%, highest in the 4th decade (40-49

years old)

This is why we often ask for a gynecologic clearance for

this age group. Rate of misdiagnosis is higher and it

could be a primarily gynecologic problem.

The highest negative appendectomy rate is reported for

women >80 years of age (this is for women overall)

Summary: the typical patient will be a male in his 20s or 30s

presenting with an acute abdomen but an appendectomy is more

often performed among women and the chances for a misdiagnosis

is higher especially among women in their 40s.

B. Etiology

Obstruction of the lumen of the appendix due to:

o

Fecalith is most common

40% of simple appendicitis

65% of gangrenous appendicitis

90% of perforated appendicitis

o

Hypertrophy of lymphoid tissue

More common in young patients because it degenerates

in teenage years

o

Inspissated barium from previous x-ray studies

o

Tumors

o Vegetable and fruit seeds

o

Intestinal parasites like ascariasis

Frequency of obstruction rises with the severity of the

inflammatory process.

C. Pathophysiology

The lumen of the appendix only has a luminal capacity of 0.1 mwhich is small in relation to its length

o This configuration may predispose to closed-loop

obstruction

o Fecalith and other debris lodge into the appendiceal lumen

and build up over time

o As little as 0.5mL of fluid distal to an obstruction raises

intraluminal pressure to 60cm H2O.

Obstruction contributes to bacterial overgrowth and despite

this, the appendix continues its function: mucus secretion

Both bacterial overgrowth and continuous mucus secretion lead

to intraluminal distention and increased wall pressure which

leads to:

o Stimulation of nerve endings of visceral afferent stretch

fibers production of vague, dull, diffuse visceral pain thatis sensed in the mid abdomen or lower epigastrium or

periumbilical region

o

Reflex nausea and vomiting

o Subsequent impairment of lymphatic (affected earlier) and

venous drainage leads to mucosal ischemia

But arterial inflow continues, resulting in engorgement and

vascular congestion

Later on there will be arterial compromise as well,

contributing to perforation

Peristalsis also stimulated by rather sudden distention so

that some cramping may be superimposed on the viscera

pain early in the course of appendicitis.

Inflammation later on involves the serosa of the appendix and

later the parietal peritoneumo This produces characteristic shift in pain to the right lowe

abdomen

The mucosa of the appendix is susceptible to impairment o

blood supply; thus, its integrity is compromised early in the

process, which allows bacterial invasion.

o Ellipsoidal infarcts: develop in the antimesenteric border

area with the poorest blood supply



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Figure 1. Factors leading to Perforation.. As distension, bacterial invasion,

compromise of the vascular supply, and infarction progress, perforation

occurs, usually on the antimesenteric border just beyond the point of

obstruction. This sequence is not inevitable, however, and some episodes of

acute appendicitis may resolve spontaneously.

Figure 2. Plain abdomen where a fecaltih can appreciated in the RLQ.

D. Microbiology

Bacteria present in the appendix is similar to those found in the

colon

o Anaerobes are most prominent!

The principal organisms that are seen in the normal appendix, in

acute appendicitis, and in perforated appendicitis are

Escherichia coli and Bacteroides fragilis, with the latter present

in greatest amounts

2nd Gen Cephalosporin and Metronidazole = first line defense

o The antibiotic coverage should include coverage for gram

positive, gram negative, and anaerobes.

o Clindamycin is rarely used because it is a causative factor of

pseudomembranous colitis

Table 1. Common Organisms seen in Patients with Acute Appendicitis

Aerobic & Facultative Anaerobic

Gram Negative

Bacilli

Escherichia coli

Pseudomonas

aeruginosa

Klebsiella sp.

Bacteroides fragilis

Other Bacteroides sp.

Fusobacterium sp.

Gram Positive

Cocci

Streptococcus

anginosus

Other Streptococcus sp.

Enterococcus species

Peptostreptococcus sp.

Gram Positive

Bacilli

Clostridium sp.

E. Symptoms

Pain usually begins as epigastric pain or periumbilical area

followed by nausea with or without vomiting

Classic localized appendicitis usually shifts to RLQ in 8 hours,

o Classic history (pain shift) only happens in about 45% of

patients and often in young males

o This again is due to irritation of the parietal peritoneum

Nausea and vomiting usually occurs AFTER onset of pain.

o

N&V is the most common associated symptom occurring in70-80% of patients

o Vomiting present only in 75% of cases

o

Gastrointestinal symptoms that develop before the onset of

pain suggest a different etiology such as gastroenteritis

Anorexia is almost always present.

Anorexia nearly always accompanies appendicitis. So

constant in fact the diagnosis of appendicitis is questioned o

the patient is not anorectic.

ABDOMINAL PAIN ANOREXIA VOMITING sequence

observed in 95% of patients with acute appendicitis

Variations:

o Sometimes pain begins in the RLQ

o

Elderly patients are difficult to diagnose due to atypical

presentation, expanded differential diagnosis and

communication difficulty (use ancillary work up like CT scan)

o Very young patients usually present with perforation.

Newborns present with generalized peritonitis because

the omentum has not developed yet to localize the

infection

o

Constipation and diarrhea - not very helpful although

majority will complain of constipation

F. Signs / Physical Exam

General Survey & Vital Signs

o

Walk slowly, prefer to lie supine due to peritoneal irritation

o Temperature is normal or mild early on

o

Pulses may also be normal or slightly elevated Pain

o Need to ask the patient to point to the area of maximal

tenderness using only one finger. Area where the patient

points is usually in the area of the appendix.

o But remember that 10-15% of patients have an appendix

located in the pelvic area will have a positive recta

examination.

Tenderness

o RLQ tenderness (often maximal at or near the McBurney’s

point)

o Direct tenderness – elicited via palpation

o

Indirect tenderness – elicited via Rovsing’s sign

o Voluntary muscle guarding - early in the disease process.

o

Involuntary muscle guarding – due to peritoneal irritationand increased muscle spasm

Signs of Peritoneal Irritation

o Cough (Dunphy’s sign), walking, bouncing

o

Tenderness is maximal at McBurney’s point at the RLQ

o

Muscular resistance or Guarding in the right iliac fossa

o

Rebound tenderness when the examiner’s hand is quickly

relieved

o Indirect tenderness or Rovsing’s sign is pain in the right

lower quadrant when the left lower quadrant is palpated

o Psoas Sign and Obturator Sign

Perforation

Distention

BacterialInvasion

CompromisedVascularSupply

Infarction

(Ellipsoidal)



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Figure 3. Psoas Sign

o Irritative focus in proximity to psoas muscle

o

Patient lie in the left side as the examiner slowly extends the

patient’s right thigh, thus stretching the psoas muscle.

o

Positive when extension produces pain.

Figure 4. Obturator Sign

o Pain upon stretching of the obturator internus muscle via

internal rotation of a flexed thigh

o Suggests inflammation near the muscle

Remember that your decision to operate will be based on your

Physical Exam. Patient with history and associated signs and

symptoms should be operated on.

G. Variability in Presentation

Table 2. Variations in the Presentation of Acute Appendicitis

Location of Appendix Location of Pain

Classic appendicitis presentation RLQ

Long appendix with tip at the LLQ LLQ

Retrocecal appendix Flank or back

Pelvic appendix Suprapubic area

Pelvic appendix with irritation of the

urinary bladder

Hypogastric area

Retroileal appendix with irritation of

spermatic artery and ureter

Testicular area

The visceral component is in the normal location

The somatic component is felt in that part of the abdomen

where the cecum has been arrested in rotation.

Remember that there is about a 10%-15% margin of error. A

disease that can commonly present as appendicitis is acute

mesenteric adenitis. In the event that you already opened up the

patient and see that the cause of RLQ is mesenteric adenitis, you

can still do an incidental appendectomy since appendicitis can

occur anytime during your lifetime.

It is also important to examine the male genitalia because there

has been incidences where they found an incarcerated inguinal

hernia, rule this out.

H. Laboratory Findings

Appendicitis is associated with an inflammatory response that is

strongly related to the severity of the disease. Laboratory

examinations are therefore an important part of the diagnosis.

WBC

o

Mild to moderate leukocytosis with a SHIFT TO THE LEFT is

the rule

Less than 4% will have normal leukocyte count (more

often seen in the elderly)o Acute uncomplicated appendicitis: mild leukocytosis

(10,000-18,000 cells/mm3) with PMN predominance

o Perforated appendix with or without abscess: >18,000

o

Complicated appendicitis: increased C-reactive protein

concentration

o Sepsis: WBC may be low due to sepsis but neutrophils will be

proportionately higher

o Appendicitis is very unlikely if the white blood cell count,

proportion of neutrophils, and CRP are normal

Urinalysis

o Important in differential diagnosis if with significant number

of RBC, WBC and bacteria to rule out UTI.

o Acute pyelonephritis, on the right side particularly, may

mimic a retroileal acute appendicitis

I. Clinical Scoring Systems

The Alvarado score

o The most widespread scoring system

o Especially useful for ruling out appendicitis and selecting

patients for further diagnostic workup.

The Appendicitis Inflammatory Response Score

o Resembles the Alvarado score but uses more graded

variables and includes CRP

o Studies have shown it to perform better than the Alvarado

score in accurately predicting appendicitis.

However, clinical scoring systems have not gained widespread

acceptance in making the diagnosis of appendicitis Remember that most of the time the diagnosis and treatment of

appendicitis will be based on your clinical findings!

J. Radiography

Plain abdomen

o Presence of fecalith and fecal loading in the cecum

o But are rarely useful for diagnosing acute appendicitis

o

Benefit is that it will help rule out other causes:

Pneumoperitonium - operate on the patient based on

ruptured viscous.

Segmental ileus - you will see small amount of dilated

small bowel called sentinel loop.

Obliteration of psoas shadow – psoas on the right is not

as clear as the left.

Chest X-Ray

o

Sometimes called to rule out referred pain from a right

lower lobe pneumonic process.

Barium enema in selected patients

o If appendix fill on barium enema then appendicitis can be

excluded.

o If appendix does not fill, no conclusion can be made.

o

Not indicated in the acute setting



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K. Graded Compression Ultrasonography

Technique is inexpensive, performed rapidly, does not require

contrast medium, and can be used in pregnant patients.

85% inflamed appendix, may rule out pelvic disease,

gynecological problems and enlarged mesenteric lymph nodes.

Appendix can be seen as a blind ending pouch originating from

the cecum. Results are considered positive if appendix measure

>6mm in the anterior posterior direction. Presence of an

appendicolith establishes diagnosis. In females of childbearing age, pelvic organs must be adequately

visualized either by transabdominal or endovaginal ultrasound

to exclude gynecologic pathology as a cause of acute abdominal

pain. Has a sensitivity of 55-96% and specificity of 85-98%

Disadvantages:

o Results are user dependent and false positives have been

reported

o False positives include periappendicits from surrounding

inflammation, dilated fallopian tube, inspissated stool which

can mimic appendicitis.

o Obese patients, the appendix may not be compressible

because of overlying fat.

Figure 5: Ultrasound showing acute appendicitis. 85% of ultrasounds done

in the RLQ will diagnose acute appendicitis. Can appreciate the lumen of the

appendix, thickened walls, and appendicolith.

Figure 6: Another ultrasound done in the longitudinal view showing similar

findings as figure 4.

Figure 7: Older generation CT scan, but can still see a markedly thickened

appendix.

L. High Resolution CT scan

Lower rates of negative appendectomy from 19% - 12%

Decreased negative appendectomies in women from 24% to 5%

Altered the care of 24%

Provided alternative diagnosis in 50%

Excellent technique for identifying other inflammatory processes

masquerading as acute appendicitis.

Appendix can perforate as early as 18 hours from onset of

symptoms.

Study done Massachusetts General Hospital where CT was done

for all patients with abdominal pain. Results showed:

o Reduced negative appendectomy from 20 to 7%

o Reduced perforation from 22% to 14%

In U.S. routinely done by ER Physicians before referred to

surgeons

Disadvantages:

o

Expensive

o Exposes the patient to significant radiation

o

Cannot be used during pregnancy

o Allergy to dye is a contraindication and some patients

cannot take oral ingestion of luminal dye due to nausea andvomiting.

Figure 8: High resolution CT scan showing dilated appendix >5cm, thickened

walls, evidence of inflammation, “dirty fat”, thickened mesoappendix,

phlegmon, fecaliths, and arrowhead sign. (Arrowhead sign is caused by

thickening of the cecum which funnels contrast agent toward the orifice of

the inflamed appendix)



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Figure 9. CT scan showing a cecal mass masquerading as an acute process.

Can also be a tuberculoma or other inflammatory conditions.

From Schwartz

The rational approach is the selective use of CT scanning. The

likelihood of appendicitis can be ascertained with the use of the

Alvarado Scale. This helps improve the diagnosis of appendicitis, by

giving weight to specific clinical manifestations.

See the appendix for Alvarado Scale and its scoring system

M. Differential Diagnosis

Essentially as diverse as that of the acute abdomen

The differential diagnosis depends upon 4 major factors:

o The anatomic location of the inflamed appendix

o

Stage of the process (e.g. simple or ruptured)

o Age of the patient

o Patient’s sex

75% includes:

o

Mesenteric adenitis

o No organic pathology seen

o

PID (pelvic inflammatory disease)

o IBD (Inflammatory bowel disorder)

Crohn’s disease – most common site is at the terminal

ileum , if you open up the patient and you see terminal

ileitis. If there’s no obstruction, do not biopsy it due to

propensity to fistulize. If the appendix is normal then

perform an incidental appendectomy. If the cecum is

involved, leave the appendix behind.

o Twisted Ovarian Cyst, Mittelschmerz

Mittelschmerz occurs in females in midcycle, pain is

caused by the irritation of the blood from the ruptured

Graafian follicle

o

Acute gastroenteritis

o Typhoid Ileitis

Other differentials:

o

PUD

o

Males: Testicular torsion, epididymitiso UTI, hernias (incarcerated)

o Meckel’s diverticulitis

o Diverticulitis

o

Ureteral colic

N. Interval Appendectomy

Done 6 to 8 weeks after the presentation of symptoms

Lower morbidity and mortality than immediate appendectomy

Greater expenses and longer hospitalization time

Failure rate is 9-15%

Major argument: 50% of patients undergoing initial conservative

treatment never develop surgical manifestations.

Non-operative option may still be applicable to those with

recurrence of appendicitis

Supporting evidences:

o 40% needed appendectomy at an earlier mean time (4.3

weeks)

o Rate of late failure: 20%

o

Continue to have recurrence: 14%

o Persistent peri-appendiceal abscess: 90%

o

Pathologic findings of acute appendicitis: 50%o Neoplasm?

Not done anymore, but in earlier times when there is a

periappendiceal abscess they treat with massive antibiotics then

after a month or two they perform an interval appendectomy

O. Rupture of the Appendix

Infection contained - soft tender mass, if you have a very

competent omentum it will cover the rupture and will have

periappendiceal abscess or if localized deep peritonitis.

o Involuntary guarding

o Rebound tenderness more marked

o Elevated temperature, tachycardia

Fails to localize - diffuse peritonitis

o

Patients

o Tenderness and guarding becomes generalized

o Temperature spikes

o

Tachycardia >100 beats per minute

From Schwartz

Immediate appendectomy has been long recommended treatment

for acute appendicitis because of the presumed risk of rupture.

Rates of perforation is 25.8%

o Children under 5 years old and >65years have the highest rates of

perforation.

Recent studies suggest that in selected patients, observation and

antibiotic therapy alone may be an appropriate treatment for acute

appendicitis.

Rupture occurs most frequently distal to the point of luminal

obstruction along the antimesenteric border of the appendix.

In 2-6% of cases and ill-defined mass is detected on PE which could

represent a phlegmon which consists of matted loops of bowel

adherent to the adjacent inflamed appendix or periappendiceal

abscess. Patients with this presentation will have experienced

symptoms for a longer duration, at least 5-7 days.

Phlegmon and small abscess can be treated conservatively with IV

antibiotics; well localized abscesses can be managed with

percutaneous drainage; complex abscess should be considered for

surgical drainage.

P. Complications

Occur in 5% of unperforated appendicitis cases, and 30% o

perforated appendicitis cases

Complications include:o

Wound infection (Surgical Site Infection) – most common

side effect

o

Intraabdominal abscess – due to break in technique

o Fecal fistula – usually secondary to a slip in the tie of the

appendiceal stub

o

Pyephlebitis – portal pyemia, does not occur anymore due

to antibiotics

o

Intestinal obstruction – occurs later on

o

Prolonged ileus

o

Pulmonary embolism



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Q.

Prognosis

Mortality rate: 0.2/100,000 appendectomies,

o 1% with rupture in general

o

5% with rupture in the elderly

Mortality is mostly seen in the extremes of ages

Principal Factor: Perforation, Age

o Morbidity parallels mortality rates

o It is significantly higher with ruptured appendicitis or old

age!

Death due to uncontrolled sepsis:

o Peritonitis

o Intra-abdominal abscess

o Gram negative septicemia

Figure 10. Laparoscopic appendectomy. Appendix is congested and

slightly enlarged or inflamed.

Figure 11. Open appendectomy. If the appendiceal stub slips off, a fecal

fistula may form and if it spreads, patient may present with peritonitis.

I. APPENDICITIS IN SPECIAL POPULATIONS

A. Appendicitis in the Young

More serious – 50-80% in pre-school children

o Higher rate of and rapid progression to rupture

o Mortality rate as high as 5%

o Later diagnosis – inability of young children to give an

accurate history and frequency of GI upsets in children

o

In one series 40% already seen by physician <1 year old

o

Rupture frequently diffuse because of a less developed

omentum – almost 100%

<5 years old

o negative appendectomy rate – 25%

o perforation rate – 45%

5-12 years old

o

negative appendectomy rate - <10%

o perforation rate – 20%

PE findings:

o Maximal tenderness in the RLQ, the inability to walk or

walking with a limp, and pain with percussion, coughing, and

hopping were found to have the highest sensitivity for

appendicitis.

o

Abdominal distension most consistent

Incidence of major complications after appendectomy in

children is correlated with appendiceal rupture

Management:o We have to operate, you cannot afford not to.

o For perforated appendicitis – generally includes immediate

appendectomy and irrigation of the peritoneal cavity. IV

antibiotics usually are given until the WBC count is norma

and the patient is afebrile for 24 hours.

o

For non-perforated appendicitis – antibiotic coverage is

limited to 24 to 48 hours.

o Laparoscopic appendectomy has been shown to be safe and

effective for the treatment of appendicitis in children.

B. Appendicitis in the Elderly

Similar but less pronounced symptomatology (since perception

of pain becomes lesser as we age)

o

30% have rupture during surgery

o Delay in diagnosis because of atypical presentation,

expanded differential diagnosis and communication

difficulty

Usually presents with lower abdominal pain, and localized RLQ

tenderness is present in only 80-90% of patients. Periumbilica

pain migrating to the RLQ is reported infrequently.

Increased comorbidities and increased rate of perforation (50

70%); postoperative morbidity, mortality and hospital length o

stay

Management: benefit more from laparoscopic approach –

reduction in complications

C.

Appendicitis during Pregnancy 1 in 2000

Most common surgical emergency in pregnancy

o

Appendicitis in pregnancy should be suspected when a

pregnant woman complains of abdominal pain of new

onset. The most consistent sign is pain in the right side of

the abdomen

Should be operated on as in non-pregnant

Displacement laterally during third trimester

Omentum also displaced cephalad

A higher rate of negative appendectomy is seen in the 2 n

trimester, and the lowest rate is in the 3rd trimester

o Difficulty attributed to the diversity of clinical presentation

secondary to the anatomic changes in the location of the

appendix during pregnancy and increased abdominal laxity.

Diagnosis is Clinical

o When diagnosis is in doubt, abdominal ultrasound may be

beneficial

o

Graded Compression Sonography

Accurate way to establish the diagnosis of appendicitis

Safe for children and pregnant women

Blind-ending nonperistaltic bowel loop originating from

the cecum

Noncompressible appendix >6mm (AP dimension)

Presence of appendicolith

Thickening of appendiceal wall



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Figure 12. (Left) Graded Compression Sonography of appendix; (Right) Acute

appendicitis in pregnancy

Management

o Incision will now be different. Usually, the appendix is more

lateral because it is being pushed by the uterus, and goes

higher in the abdomen as the baby grows.

o But you still have to ask where the point of maximal

tenderness is.

II. MECKEL’S DIVERTICULUM

A.

Introduction

When you do your appendectomy, examine the distal 2/5ths of

your small intestine because 2% will have Meckel’s diverticulum

Most prevalent congenital anomaly of the GIT

REMEMBER THE RULE OF 2’S!

o 2% prevalence rate

o

2:1 Female:Male ratio

o Located 2 ft. from the ileocecal valve

o

Symptoms: <2 years of age

The most common cause of bleeding in 2 year olds is Meckel’s

diverticulum, due to the presence of gastric mucosa in the

diverticulum. Small intestines cannot tolerate the acidic content

and it leads to bleeding

60% contains heterotopic mucosa, of which 60% consists of

gastric mucosa

o

Next most common is the presence of pancreatic acini

o Others:

Brunner’s glands

Pancreatic islets

Colonic mucosa

Endometriosis

Hepatobiliary tissue

in Meckel’s diverticulum, only the mucosa is involved versus

Crohn’s disease wherein all layers are involved given that it’s

intramural

B. Pathophysiology

Normally, at the 8th week of gestation the omphalomesenteric(vitelline) duct normally undergoes obliteration

Meckel’s diverticulum arises from the failure of vitelline duct

obliteration

Other abnormalities include:

o Omphalomesenteric fistula

o Enterocyst

o Fibrous band connecting the intestine to the umbilicus

o

Mesodiverticular band- remnant of left vitelline artery

Bleeding – secondary to heterotropic gastric mucosa located

within the diverticulum; the intestines cannot tolerate the high

acidity of the gastric mucosa

Obstruction can result from either of the following:

o

Volvulus of the intestine around the fibrous band attaching

the diverticulum to the umbilicus

o

Entrapment of intestine by a mesodiverticular band

o Intussusception with the diverticulum acting as a lead point

o

Stricture secondary to chronic diverticulitis

Figure 13. Picture of a resected Meckel’s diverticulum

C. Clinical Presentation

Usually presents asymptomatically

Lifetime incidence of complications is 4-6% and this does no

change with age

o

Very low complication rate. Not routinely removed becausethere may be more complications if you remove it electively.

Can present with:

o Bleeding – most common presentation in children. Rare

among those 30 y.o and older

o Intestinal obstruction – most common presentation in adults

o Diverticulitis – indistinguishable from acute appendicitis

D. Diagnosis

Majority are incidental findings on radiographic imaging

endoscopy, or at the time of surgery

It is rarely diagnosed pre-operatively, unless there is bleeding

CT Scan – has low sensitivity

EnterocolysiS – 75% accuracy, not applicable in acutepresentation

Radionuclide Scans – positive only when ectopic gastric mucosa

is capable of uptake of tracer, 90% accurate in pediatric patients

but less than 50% accurate in adults

Angiography – used to localize the bleeding

Figure 14. Radionuclide scan diagnosing Meckel’s diverticulum. It has

affinity for gastric cells. You can see absorption of the radionuclide material

(green arrow), which is a Meckel’s diverticulum.



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E. Treatment

Diverticulectomy with removal of associated bands

Segmental resection of ileum that includes both the

diverticulum and the adjacent ileal peptic ulcer for:

o Bleeding

o

Diverticulum contains tumor

o Inflamed or perforated base

Treatment in asymptomatic cases is controversial

o

This condition usually has a low complication rate and morecomplications may arise if you operate on this.

o If you do an appendectomy and you have an incidental

finding of Meckel ’ s, you may leave it alone and just note it

for future procedures

An indication for surgery is obstruction.

III.

APPENDICEAL TUMORS

Appendiceal malignancies are extremely rare

o Diagnosed in 0.9 to 1.4% of appendectomy specimens

o

0.12 cases/1,000,000 people

Rarely diagnosed pre-operatively

o Fewer than 50% are diagnosed at operation

Carcinoid – most common (>50%) appendiceal malignancyo Mucinous adenocarcinoma – 38%

o

Adenocarcinoma – 26%

o Carcinoid – 17%

o Goblet cell CA – 15%

o Signet Ring CA – 4%

Survival

o Carcinoid – 83% 5 year survival

o

Signet Ring – 18% 5 year survival

A. Carcinoid

Small, firm, yellow-brown tumor

Most common appendiceal malignancy

o 45% of GI carcinoids

o

Appendix is the most common site of GI carcinoid, followedby the small bowel and then the rectum

Biologic malignancy in 2.9%

o

Rare cases of malignant carcinoid syndrome

Symptoms are rare although the tumor can occasionally obstruct

the appendiceal lumen like a fecalith and result in acute

appendicitis

o

¾ occur in the distal third or tip of the appendix

Management:

Figure 15. Management of Appendiceal Carcinoid

B. Adenocarcinoma

Colonic type in contrast to malignant mucocele

X-ray may show extracecal mass

Usually not diagnosed preoperatively

Prognosis is about the same as in cecal cancer

Common mode of presentation is acute appendicitis, but may

also present with ascites or a palpable mass.

Treatment: Right hemicolectomy

High rate of synchronous and metachronous neoplasms

3 histologic subtypes:

o Mucinous adenoCA

o Colonic adenoCA

o Adenocarcinoid

C. Mucocele

A benign, obstructive, cystic dilatation by intralumina

accumulation of mucoid material

May be caused by one of four processes:

o Retention Cyst

o Mucosal Hyperplasia

o Cystadenoma

o

Cystadenocarcinoma Presentation

o

Nonspecific, and often an incidental finding

o RLQ discomfort or mass

o X-ray shows filling defect in cecum with absent appendix

An intact mucocele presents no risk

o

But if the mucocele has ruptured and epithelial cells have

escaped into the peritoneal cavity open laparotomy is

recommended. Laparotomy allows for thorough abdominal

exploration to rule out the presence of mucoid fluid

accumulations.

o If you rupture the mucocele which can be a grade I

mucinous papillary adenocarcinoma, you could have

pseudomyxoma peritonei

Pseudomyxoma peritonei – a rare condition in which diffuse

collections of gelatinous fluid are associated with mucinous implants

on peritoneal surfaces and omentum, more common in females

than in males. Majority originate from the appendix. Patients

present with abdominal pain, distension or a mass.

Management:

o

Appendectomy plus wide resection of the mesoappendix

and lymph nodes

o

Cytology of intraperitoneal mucous

o Inspect base of appendix

o

Right hemicolectomy if positive margin at the base of the

appendix or positive periappendiceal lymph nodes (when

appendix is involved)o For ruptured appendiceal neoplasms, initial laparotomy

with subsequent referral to a specialized center fo

consideration of re-exploration and hyperthermic

intraperitoineal chemotherapy.



Surgery II 3.1a

of 9

D. Lymphoma

The GI tract is the most frequently involved extranodal site for

Non-Hodgkin’s lymphoma

Primary lymphoma of the appendix accounts for 1-3% of GI

lymphomas

Presentation: Acute Appendicitis

CT scan: Appendiceal diameter >2.5cm or surrounding soft tissue

thickening

Management

o Localized to appendix: Appendectomy

o Extends beyond the appendix onto the cecum or mesentery:

Right Hemicolectomy

o A post-operative staging workup is indicated before

initiating adjuvant therapy. Adjuvant therapy is not indicated

for lymphoma confined to the appendix.

surgery ii 3.1a appendix - dr. haw

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