surgery_1.3 appendix (book).docx

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Suzie, Patsu, Charlie Page 1of 10

I.3Appendix (Book)Schwartz, 9thed

July 2, 2013

BACTERIOLOGY

Bacteriology of the normal appendixis similarto thatof the normal colon.

Bacteria cultured in cases of appendicitis are thereforesimilar to those seen in other colonic infections such asdiverticulitis.

The principal organisms seen in the normal appendix, inacute appendicitis, and in perforated appendicitis are: Escherichia coli and Bacteroides fragilis However, a wide variety of both facultativeand

anaerobicbacteria and mycobacteriamay bepresent.

Appendicitis is a polymicrobial infection, with someseries reporting up to 14different organisms culturedin patients with perforation.

The routine use of intraperitoneal cultures in patientswith either perforated or nonperforated appendicitis isquestionable.

As discussed above, the flora is known and thereforebroad-spectrum antibioticsare indicated.

By the time culture results are available, the patientoften has recovered from the illness.

Additionally, the number of organisms cultured and theability of a specific lab to culture anaerobic organismsvary greatly.

Peritoneal cultureshould be reserved for patientswho are immunosuppressed, and for patients whodevelop an abscess after the treatment of appendicitis.

Antibiotic coverage is limited to: 2448 h in cases ofnonperforated appendicitis. For perforated appendicitis, 710 daysis

recommended.

Intravenous antibiotics are usually given until the whiteblood cell count is normal and the patient is afebrile for24 h.

CLINICAL MANIFESTATIONSSYMPTOMS

ABDOMINAL PAIN is the prime symptom of acuteappendicitis.

Initially,pain is diffuselycentered in the lowerepigastrium or umbilical area, is moderately severe,and is steady, sometimes with intermittent crampingsuperimposed.

After a period varying from 112 h, the painlocalizesto the right lower quadrant.

This classic pain sequence, although usual, is notinvariable.

In some patients, the pain of appendicitis begins in theright lower quadrant and remains there.

Variations in the anatomic location of theappendix = variations in the principal locus of thesomatic phase of the pain.

Anorexianearly always accompanies appendicitis. It isso constant that the diagnosis should be questioned ifthe patient is not anorectic.

Although vomiting occurs in 75 percent of patients,it is neither prominent nor prolonged.

Most patients give a history of obstipationbeginningprior to the onset of abdominal pain, and many feelthat defecation would relieve their abdominal pain.

However, diarrheaoccurs in some patients,particularly children, so that the pattern of bowel

function is of little differential diagnostic value. The sequence of symptom appearancehas great

differential diagnostic significance. In more than 95 percent of patients with acute

appendicitis: Anorexia is the first symptom, followed by abdominal pain, then, vomiting.

If vomiting precedes the onset of pain, the diagnosis ofappendicitis should be questioned.

SIGNS Physical findings are determined principally by:

anatomic positionof the inflamed appendix, whether the organ has already rupturedwhen

the patient is first examined.

Vital signs are minimally changed by uncomplicatedappendicitis. Temperature elevation is rarely more than 1C

(33.8F) Pulse rate is normal or slightly elevated.

Changes of greater magnitudeusually indicate thata complication has occurred or that another diagnosisshould be considered.

Patients with appendicitis usually prefer to lie supine,with the thighs, drawn up, because any motionincreases pain.

The classic right lower quadrant physical signsarepresent when the inflamed appendix lies in theanterior position.

Tenderness is often maximal at or near the McBurneypoint.

Direct rebound tenderness is usually present. Additionally, referred or indirect rebound tenderness is

present. This referred tendernessis felt maximally inthe right lower quadrant, indicating localizedperitoneal irritation.

The Rovsing signpain in the right lower quadrantwhen palpatory pressure is exerted in the left lowerquadrantalso indicates the site of peritoneal irritation.

Cutaneous hyperesthesia in the area supplied by thespinal nerves on the right at T10, T11, and T12

frequently accompanies acute appendicitis. Muscular resistanceto palpation of the abdominal

wallparallelsthe severity of the inflammatoryprocess. Anatomic variations in the position of the inflamed

appendix lead to deviations in the usual physicalfindings.

The psoas signindicates an irritative focus inproximity to that muscle. The test is performed byhavingpatients lay on their left side as the examinerslowly extends the right thigh, thus stretching theiliopsoas muscle. The test is positive if extensionproduces pain.

Similarly, a positive obturator signof hypogastric painon stretching the obturator internusindicates irritationin the pelvis. The test is performed by passive internalrotation of the flexed right thigh with the patientsupine.

LABORATORY FINDINGS

Mild leukocytosis, ranging from 10,00018,000/mm3, is usually present in patients withacute, uncomplicated appendicitis and is oftenaccompanied by a moderate polymorphonuclearpredominance.

However, white blood cell counts are variable.


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I.3 - Appendix (Book)Page 2of 10

It is unusual for the white blood cell count to begreater than18,000/mm3in uncomplicatedappendicitis.

White blood cell counts above this levelraise thepossibility of a perforated appendix.

Urinalysis is useful to rule out the urinary tract as thesource of infection.

Although several white or red blood cells can bepresent from ureteral or bladder irritation as a result ofan inflamed appendix, bacteriuriain catheterized

urine specimen is not seen with acute appendicitis.

IMAGING STUDIESPLAIN FILMS OF THE ABDOMEN

Although frequently obtained as part of the generalevaluation of a patient with an acute abdomen, arerarely helpful in diagnosing acute appendicitis.

However, plain radiographs can be of significant benefitin ruling out other pathology.

In patients with acute appendicitis, one often sees anabnormal bowel gas pattern, which is a nonspecificfinding.

The presence of a fecalith is rarely noted on plain films,but if present, is highly suggestive of the diagnosis.

GRADED COMPRESSION SONOGRAPHY Has been suggested as an accurate way to establish

the diagnosis of appendicitis. The technique is inexpensive, can be performed rapidly,

does not require contrast, and can be used in pregnantpatients.

Sonographically, the appendix is identified as a blind-ending, nonperistaltic bowel loop originating from thececum.

With maximal compression, the diameter of theappendix is measured in the anteroposterior dimension.

A scan is considered positive if a noncompressibleappendix 6 mm or greaterin the anteroposterior

direction is demonstrated. Thepresence of an appendicolith establishes the

diagnosis. The presence of thickening of the appendiceal wall and

periappendiceal fluid is highly suggestive. Sonographic demonstration of a normal appendix

excludes the diagnosis of acute appendicitis.

The study is considered inconclusive if the appendix isnot visualized and there is nopericecal fluid or mass.

When the diagnosis of acute appendicitis is excluded bysonography, a brief survey of the remainder of theabdominal cavity should be performed to establish analternative diagnosis.

In females of child-bearing age, the pelvic organs mustbe adequately visualized.

The sonographic diagnosis of acute appendicitis has areported sensitivity of 5596 percentand aspecificity of 8598 percent.

Some studies have reported that graded compressionsonography improved the diagnosis of appendicitis overclinical exam, specifically decreasing the percentage ofnegative explorations for appendectomies from 37down to 13percent.

Sonography also decreases the time before operation. Sonography identified appendicitis in 10 percent of

patients who were believed to have a low likelihood of

the disease on physical examination. The positive and negative predictive values of

ultrasonography have been reported as 91 or92percent, respectively.

However, in a recent prospective multicenter study,routine ultrasonography did not improve the diagnosticaccuracy or rates of negative appendectomy orperforation when compared to clinical assessment.

HIGH-RESOLUTION, HELICAL, COMPUTERTOMOGRAPHY

Also has been used to diagnose appendicitis. On CT scan, the inflamed appendix appears dilated and

the wall is thickened.

There is usually evidence of inflammation, with dirtyfat, thickened mesoappendix, and even an obviousphlegmon.

Fecaliths can be easily visualized, but their presence isnot necessarily pathognomonic of appendicitis.

An important suggestive abnormality is the arrowheadsign. This is caused by thickening of the cecum, whichfunnels contrast toward the orifice of the inflamedappendix.

CT scanning is also an excellent technique foridentifying other inflammatory processes masqueradingas appendicitis.

Several CT techniques have been used, includingfocused and nonfocused CT scans and enhanced andnonenhanced helical CT scanning.

Surprisingly, all these techniques have yielded similarrates of diagnostic accuracy, i.e., 9297 percentsensitivity, 8594 percent specificity, 9098 percentaccuracy, and 7595 percent positive and 9599percent negative predictive values.

A number of studies have documented improvement indiagnostic accuracy with the liberal use of CT scanningin the workup of suspected appendicitis.

Computed tomography lowered the rate of negativeappendectomies from 19 down to 12 percent in onestudy, and the incidence of negative appendectomies inwomen from 24 down to 5 percent in another.

The use of this imaging study altered the care of 24percent of patients studied and provided alternativediagnoses in half of the patients with normalappendices on CT scan.

Problems exist with routine CT scanning for suspectedappendicitis. CT scanning is expensive, exposes thepatients to significant radiation, and cannot be usedduring pregnancy.

Allergy contraindicates the application of intravenouscontrast in some patients, and others cannot toleratethe oral ingestion of luminal dye, particularly in the

presence of nausea and vomiting. Finally, not all studies have documented the utility of

CT scanning in all patients with right lower quadrantpain.

Studies comparing the effectiveness of ultrasound tohelical CT in establishing the diagnosis of appendicitishave demonstrated CT scanning superior.

In one study, 600 ultrasounds and 317 CT scansrevealed sensitivities of 80 and 97 percent, specificitiesof 93 and 94 percent, diagnostic accuracies of 89 and95 percent, positive predictive values of 91 and 92percent, and negative predictive values of 88 and 98percent, respectively.

In another study, ultrasound positively impacted themanagement of 19 percent of patients, as compared to73 percent of patients for CT.

Finally, in a third study, patients studied byultrasonography had a 17 percent negative appendixrate compared to a 2 percent negative appendix rate in

patients who underwent helical CT scanning. One issue that has not been resolved is which patients

are candidates for imaging studies. The concept that all patients with right lower quadrant

pain should undergo CT scanning has been stronglysupported by two reports by Rao and his colleagues atthe Massachusetts General Hospital.

In one, this group documented a fall in the negativeappendectomy rate from 20 down to 7 percent, and a

decline in the perforation rate from 22 down to 14percent, and establishing an alternative diagnosis in 50percent of patients.

In the second study, published in the New EnglandJournal of Medicine, they documented that CT scanningprevented 13 unnecessary appendectomies, saved 50inpatient hospital days, and lowered the per patientcost by $447.

In contrast, several studies failed to prove anadvantage of routine CT scanning, documenting thatsurgeon accuracy approached that of the imaging study


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and expressing concern that the imaging studies couldadversely delay appendectomy in affected patients.

The rational approach is the selective use of CTscanning. This has been documented by several

studies in which imaging was performed based on analgorithm or protocol.

The likelihood of appendicitis can be ascertained usingthe Alvarado scale.

This scoring system was designed to improve thediagnosis of appendicitis and was devised by giving

relative weight to specific clinical manifestation.

LAPAROSCOPY Can serve as both a diagnosticand therapeutic

maneuverfor patients with acute abdominal pain andsuspected acute appendicitis.

Laparoscopy is most useful in the evaluation of femaleswith lower abdominal complaintsbecauseappendectomy is performed on a normal appendix in asmany as 3040 percent of these patients.

Differentiating acute gynecologic pathology from acuteappendicitis can be effectively accomplished by usingthe laparoscope.

APPENDICEAL RUPTURE Immediate appendectomy has long been the

recommended treatment of acute appendicitis becauseof the risk of rupture.

The overall rate of perforated appendicitis is 25.8percent.

Children younger than age 5 years (45%)andpatients older than age 65 years (51%)have thehighest rate of perforation.

It has been suggested that delays in presentation areresponsible for the majority of perforated appendices.

There is no accurate way of determining when and if anappendix will rupture prior to resolution of theinflammatory process.

Although it has been suggested that observation and Antibiotic therapy alone may be an appropriate

treatment for acute appendicitis, nonoperativetreatment exposes the patient to the increasedmorbidity and mortality associated with a rupturedappendix.

Appendiceal rupture should be suspected in thepresence of fever greater than 39C (102F) and awhite blood cell count greater than 18,000/mm3.

In the majorityof cases, rupture is contained andpatients display localized rebound tenderness.

Generalized peritonitis will be present if the walling-offprocess is ineffective in containing the rupture.

In 26 percent of cases, an ill-defined mass will bedetected on physical examination.

This could represent a phlegmon or a periappendicealabscess.

Patients who present with a mass have a longerduration of symptoms, usually at least 57 days.

The ability to distinguish acute, uncomplicatedappendicitis from acute appendicitis with perforation onthe basis of clinical findings is often difficult, but it isimportant to make the distinction because theirtreatment differs.

CT scan may be beneficial in guiding therapy. Phlegmons and small abscessescan be treated

conservatively with intravenous antibiotics; welllocalized abscessescan be managed with

percutaneous drainage; complex abscessesshouldbe considered for surgical drainage.

If operative drainage is required, it should be

performed by using an extraperitoneal approach, withappendectomy reserved for cases in which theappendix is easily accessible.

Interval appendectomyperformed at least 6 weeksfollowing the acute event has classically beenrecommended for all patients treated eithernonoperatively or with simple drainage of an abscess.

DIFFERENTIAL DIAGNOSIS The differential diagnosis of acute appendicitisis

essentially the diagnosis of the acute abdomen. This is because clinical manifestations are not

specific for a given disease, but are specific fordisturbance of a physiologic function or functions.

Thus, an essentially identical clinical picture can resultfrom a wide variety of acute processes within or nearthe peritoneal cavity.

The accuracy of preoperative diagnosis should beapproximately 85 percent.

If it is consistently less, it is likely that someunnecessary operations are being performed, and amore rigorous preoperative differential diagnosis is inorder.

A diagnostic accuracy rate consistently greater than90 percentshould also cause concern, because thismay mean that some patients with atypical, but bonafide cases of, acute appendicitis are being observedwhen they should haveprompt surgical intervention.

The Haller group has shown, however, that this is notinvariably true. Before the groups study, the perforation rateat

the hospital in which the study took place was 26.7percent, and acute appendicitis was found in 80percentof the operations.

By a policy of intensive in-hospital observation whenthe diagnosis of appendicitis was unclear, the groupraised the rate of acute appendicitisfound atoperation to 94 percent, although the perforation

rate remained unchanged at 27.5 percent. There are a few conditions in which operation is

contraindicated. Other disease processes that are confused with

appendicitis are also surgical problems, or, if not, arenot made worse by surgical intervention.

A common error is to make a preoperative diagnosis ofacute appendicitis only to find some other condition (ornothing) at operation; much less frequently, acuteappendicitis is found after a preoperative diagnosis ofanother condition.

The most common erroneous preoperative diagnosesaccounting for more than 75 percentin descendingorder of frequency are:

1. acute mesenteric lymphadenitis,2. no organic pathologic conditions,3. acute pelvic inflammatory disease,4. twisted ovarian cyst or ruptured graafian

follicle,

5. acute gastroenteritis.The differential diagnosis of acute appendicitisdepends on FOUR MAJOR FACTORS:1. the anatomic location of the inflamed appendix2. the stage of the process (i.e., simple or ruptured)3. the patients age4. the patients sex

ACUTE MESENTERIC ADENITIS

Disease most often confused with acute appendicitis inchildren.

Almost invariably, an upper respiratory infectionispresent or has recently subsided.

The pain is usually diffuse and tenderness is not assharply as localized as in appendicitis.

Voluntary guarding is sometimes present, but truerigidity is rare.

Generalized lymphadenopathymay be noted. Laboratory procedures are of little help in arriving at

the correct diagnosis, although a relative


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lymphocytosis, when present, suggests mesentericadenitis.

Observation for several hours is in order if thediagnosis of mesenteric adenitis seems likely, because

it is a self-limited disease. However, if the differentiation remains in doubt,

immediate exploration is the safest course of action

GYNECOLOGIC DISORDERS

PELVIC INFLAMMATORY DISEASE

Infection usually is bilateral If confined to the right tube, may mimic acute

appendicitis Nausea and vomiting are present in patients with

appendicitis, but in only approximately 50%of thosewith pelvic inflammatory disease

Pain and tenderness are usually lower, and motion ofthe cervix is exquisitely painful.

Intracellular diplococcimay be demonstrable onsmear of the purulent vaginal discharge.

The ratio of cases of appendicitis to cases of pelvicinflammatory disease is low in femalesin the earlyphase of the menstrual cycle and high during the lutealphase.

The careful clinical use of these features has reducedthe incidence of negative findings on laparoscopy inyoung women to 15%.

RUPTURED GRAAFIAN FOLLICLE

Ovulation commonly results in the spillage of sufficientamounts of blood and follicular fluid to produce brief,mild lower abdominal pain.

If the amount of fluid is unusually copious and is fromthe right ovary, appendicitis may be simulated. Painand tenderness are rather diffuse.

Leukocytosis and fever are minimal or absent. Becausethis pain occurs at the midpoint of the menstrual cycle,it is often called MITTELSCHMERZ.

TWISTED OVARIAN CYST

Serous cysts of the ovary are common and generallyremain asymptomatic

When right-sided cystsrupture or undergo torsion,the manifestations are similar to those of appendicitis.

Patients develop right lower quadrant pain, tenderness,rebound, fever, and leukocytosis.

If the mass is palpable on physical examination, thediagnosis can be made easily.

Both transvaginal ultrasonographyand CTscanningcan be diagnostic if a mass is not palpable.

Torsion requires emergent operative treatment. If the torsion is complete or longstanding, the pedicle

undergoes thrombosis, and the ovary and tube becomegangrenous and require resection.

Leakage of ovarian cysts resolves spontaneously,however, and is best treated nonoperatively.

RUPTURED ECTOPIC PREGNANCY

Blastocysts may implant in the fallopian tube (usuallythe ampullary portion) and in the ovary.

Rupture of right tubal or ovarian pregnancies can mimicappendicitis.

Patients may give a history of abnormal menses,either missing one or two periods or noting only slightvaginal bleeding.

Right lower quadrant or pelvic painmay be the firstsymptom.

The diagnosis of ruptured ectopic pregnancy should berelatively easy.

The presence of a pelvic massand elevated levels ofchorionic gonadotropinare characteristic. Althoughthe leukocyte count rises slightly (to approximately14,000 cells/mm3), the hematocrit level falls as aconsequence of the intra-abdominal hemorrhage.

Vaginal examination reveals cervical motionandadnexal tenderness

More definitive diagnosis can be established byculdocentesis.

Presence of blood and particularly decidual tissueispathognomonic.

Treatment is emergency surgery.GASTROENTERITIS

Acute gastroenteritis is common but usually can beeasily distinguished from acute appendicitis.Gastroenteritis is characterized by profuse diarrhea,nausea, and vomiting.

Hyperperistaltic abdominal cramps precede the waterystools.

The abdomen is relaxed between cramps, and there areno localizing signs.

OTHER INTESTINAL MANIFESTATIONS

MECKELS DIVERTICULITIS

gives rise to a clinical picture similar to that of acuteappendicitis

located within the distal 2 ftof the ileum Associated with the same complications as appendicitis

and requires the same treatmentprompt surgicalintervention.

Resection of the segment of ileum bearing thediverticulum with end-to-end anastomosis can nearly

always be done through a McBurney incision,extended if necessary, or laparoscopically.

CROHNS ENTERITIS

The manifestations of acute regional enteritisfever,right lower quadrant pain and tenderness, andleukocytosisoften simulate acute appendicitis.

The presence of diarrhea and the absence of anorexia,nausea, and vomiting favor a diagnosis of enteritis, butthis is not sufficient to exclude acute appendicitis.

In an appreciable percentage of patients with chronicregional enteritis, the diagnosis is first made at thetime of operation for presumed acute appendicitis.

In cases of an acutely inflamed distal ileum with nocecal involvement and a normal appendix,appendectomyis indicated.

Progression to chronic Crohn's ileitis is uncommon.COLONIC LESIONS

Diverticulitis or perforating carcinoma of the cecum, orof that portion of the sigmoid that lies in the right side,may be impossible to distinguish from appendicitis.

These entities should be considered in older patients. CT scanning is often helpful in making a diagnosis in

older patients with right lower quadrant pain andatypical clinical presentations.

Epiploic appendagitisprobably results from infarctionof the colonic appendage(s) secondary to torsion.

Symptoms may be minimal, or there may becontinuous abdominal pain in an area corresponding tothe contour of the colon, lasting several days.

Pain shift is unusual, and there is no diagnosticsequence of symptoms.

The patient does not look ill, nausea and vomiting areunusual, and appetite generally is unaffected.

Localized tenderness over the site is usual and often isassociated with rebound without rigidity.

In 25%of reported cases, pain persists or recurs untilthe infarcted epiploic appendage is removed.

ACUTE APPENDICITIS IN YOUNG

Diagnosis of acute appendicitis is more difficult inyoung children than in the adult.

The inability of young children to give an accuratehistory, diagnostic delays by both parents andphysicians, and the frequency of GI upset in childrenare all contributing factors.

In children the physical examination findings ofmaximal tenderness in the right lower quadrant, theinability to walk or walking with a limp, and pain withpercussion, coughing, and hopping were found to havethe highest sensitivity for appendicitis.


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43%of patients were found to have perforatedappendicitis at laparotomy.

The increased risk of appendiceal rupturemay berelated to the delayin presentation seen in this patient

population The mean duration of symptoms before arrival in the

emergency department has been reported to beincreased in HIV-infected patients, with >60%ofpatients reporting the duration of symptoms to belonger than 24 hours.

In early series, significant hospital delay also may havecontributed to high rates of rupture. However, withincreased understanding of abdominal pain in HIV-infected patients, hospital delay has become lessprevalent.

A low CD4count is also associated with an increasedincidence of appendiceal rupture. In one large series,

patients with nonruptured appendices had CD4 countsof 158.75 47 cells/mm3compared with 94.5 32cells/mm3in patients with appendiceal rupture.

The differential diagnosis of right lower quadrant pain isexpanded in HIV-infected patients compared with thegeneral population.

Opportunistic infections should be considered as apossible cause of right lower quadrant pain.

Such opportunistic infections include cytomegalovirus(CMV) infection, Kaposi's sarcoma, tuberculosis,lymphoma, and other causes of infectious colitis.

CMV infection causes a vasculitis of blood vessels in thesubmucosa of the gut, which leads to thrombosis.

Mucosal ischemia develops, leading to ulceration,gangrene of the bowel wall, and perforation.

Spontaneous peritonitis may be caused by opportunisticpathogens, including CMV, Mycobacterium avium-intracellularecomplex, Mycobacterium tuberculosis,Cryptococcus neoformans, and Strongyloides.

Kaposi's sarcoma and non-Hodgkin's lymphoma maypresent with pain and a right lower quadrant mass.

Viral and bacterial colitisoccur with a higherfrequency in HIV-infected patients than in the generalpopulation.

Colitis should always be considered in HIV-infectedpatients presenting with right lower quadrant pain

Neutropenic enterocolitis (typhlitis)should also beconsidered in the differential diagnosis of right lowerquadrant pain in HIV-infected patients.

In the HIV-infected patient with classic signs andsymptoms of appendicitisimmediate appendectomyis indicated.

In those patients with diarrhea as a prominentsymptom, colonoscopymay be warranted.

In patients with equivocal findings, CT scanis usuallyhelpful.

The majority of pathologic findings identified in HIV-infected patients who undergo appendectomy forpresumed appendicitis are typical.

The negative appendectomy rate is 5 to 10%.However, in up to 25%of patients AIDS-relatedentities are found in the operative specimens, includingCMV, Kaposi's sarcoma, and M. avium-intracellularecomplex.

More recent series report 0% mortality in this group ofpatients.

Morbidity rates for HIV-infected patients withnonperforated appendicitis are similar to those seen inthe general population.

Postoperative morbidity rates appear to be higher inHIV-infected patients with perforated appendicitis.

The length of hospital stay for HIV-infected patientsundergoing appendectomy is twice that for the generalpopulation.

No series has been reported to date that addresses therole of laparoscopic appendectomy in the HIV-infectedpopulation.

TREATMENT Once the decision to operate for presumed acute

appendicitis has been made, the patient should beprepared for the operating room.

Adequate hydrationshould be ensured, electrolyteabnormalities should be corrected, and pre-existingcardiac, pulmonary, and renal conditions should beaddressed.

A large meta-analysis has demonstrated the efficacy ofpreoperative antibioticsin lowering the infectious

complications in appendicitis. Most surgeons routinely administer antibiotics to all

patients with suspected appendicitis. If simple acute appendicitisis encountered, there is

no benefit in extending antibiotic coverage beyond 24hours.

If perforated or gangrenousappendicitis is found,antibiotics are continued until the patient is afebrile andhas a normal white blood cell count.

For intra-abdominal infectionsof GI tract origin thatare of mild to moderate severity, the Surgical InfectionSociety has recommended single-agent therapy withcefoxitin, cefotetan, or ticarcillin-clavulanic acid.

For more severe infections, single-agent therapy withcarbapenems or combination therapy with a third-generation cephalosporin, monobactam, oraminoglycoside plus anaerobic coverage withclindamycin or metronidazole is indicated.

The recommendations are similar for childrenOPEN APPENDECTOMY

For open appendectomy most surgeons use either aMcBurney (oblique) or Rocky-Davis (transverse)right lower quadrant muscle-splitting incision inpatients with suspected appendicitis.

The incision should be centered over either the point ofmaximal tenderness or a palpable mass.

If an abscess is suspected, a laterally placed incisionis imperative to allow retroperitoneal drainage and toavoid generalized contamination of the peritonealcavity.

If the diagnosis is in doubt, a lower midline incisionis recommended to allow a more extensive examinationof the peritoneal cavity.

This is especially relevant in older patients with possiblemalignancy or diverticulitis.

Several techniques can be used to locate the appendix. Because the cecumusually is visible within the

incision, the convergence of the taeniae can be followedto the base of the appendix.

A sweeping lateral to medialmotion can aid indelivering the appendiceal tip into the operative field.

Occasionally, limited mobilization of the cecum isneeded to aid in adequate visualization.

Once identified, the appendix is mobilized by dividingthe mesoappendix, with care taken to ligate theappendiceal artery securely.

The appendiceal stump can be managed by simpleligation or by ligation and inversion with either apurse-stringor Z stitch.

As long as the stump is clearly viable and the base ofthe cecum is not involved with the inflammatoryprocess, the stump can be safely ligated with anonabsorbable suture.

The mucosa is frequently obliterated to avoid thedevelopment of mucocele.

The peritoneal cavity is irrigated and the wound closedin layers. If perforation or gangrene is found in adults,the skin and subcutaneous tissue should be left openand allowed to heal by secondary intent or closed in 4to 5 daysas a delayed primary closure.

In children, who generally have little subcutaneous fat,primary wound closurehas not led to an increasedincidence of wound infection.

If appendicitis is not found, a methodical search mustbe made for an alternative diagnosis.

The cecum and mesentery should first be inspected.


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Next, the small bowel should be examined in aretrograde fashion beginning at the ileocecal valve andextending at least 2 ft. In females, special attentionshould be paid to the pelvic organs.

An attempt also should be made to examine the upperabdominal contents.

Peritoneal fluid should be sent for Gram's staining andculture.

If purulent fluid is encountered, it is imperative that thesource be identified.

A medial extension of the incision (Fowler-Weir),with division of the anterior and posterior rectussheath, is acceptable if further evaluation of the lowerabdomen is indicated.

If upper abdominal pathology is encountered, the rightlower quadrant incision is closed and an appropriateupper midline incision is made

LAPAROSCOPIC APPENDECTOMY Semm- first reported successful laparoscopic

appendectomy several years before the firstlaparoscopic cholecystectomy. However

Did not come into widespread use until after thesuccess of laparoscopic cholecystectomy due to the fact

that appendectomy is already a form of minimal-accesssurgery.

Performed under general anesthesia. A nasogastric tube and a urinary catheter are placed

before obtaining a pneumoperitoneum The surgeon usually stands to the patient's left and one

assistant is required to operate the camera.

Usually requires the use of three ports. Four portsmay occasionally be necessary to mobilize a retrocecalappendix. 1STtrocar (10 mm)-placed in the umbilicus 2ndtrocar- placed in the suprapubic position or left

lower quadrant. The suprapubic trocar is either,depending on whether or not a linear stapler will be

used. 3rd trocar (5 mm)- variable and usually is either in

the left lower quadrant, epigastrium, or right upperquadrant. Placement is based on location of theappendix and surgeon preference.

Initially, the abdomen is thoroughly explored to excludeother pathology.

Appendix is identified by following the anterior taeniaeto its base.

Dissection at the base of the appendix enables thesurgeon to create a window between the mesenteryand the base of the appendix.

A.A window is created in the mesoappendix close to the baseof the appendix B.The linear stapler is used to divide the

appendix at its base. C. Finally, the mesoappendix can be easilydivided using the linear stapler

The mesentery and base of the appendix are thensecured and divided separately.

When the mesoappendix is inflamed, it is oftenbest to divide the appendix firstwith a linear staplerand then to divide the mesoappendix immediately

adjacent to the appendix with clips, electrocautery,Harmonic Scalpel, or staples.

The base of the appendix is not inverted. The appendixis removed from the abdominal cavity through a trocar

site or within a retrieval bag. The base of the appendix and the mesoappendix should

be evaluated for hemostasis, right lower quadrantshould be irrigated and Trocars are removed underdirect vision.

Wound infections were approximately half as likely afterlaparoscopic appendectomy as after openappendectomy. However, the rate of intra-abdominalabscess was three times higher after laparoscopicappendectomy than after open appendectomy.

PRINCIPAL PROPOSED BENEFITOFLAPAROSCOPICAPPENDECTOMY

Decreased postoperative pain- significantly lesspain after laparoscopic appendectomy on the 1stpostoperative day.

Shorter length of hospital stay- less afterlaparoscopic appendectomy. It appears that a moreimportant determinant of length of stay afterappendectomy is the pathology found at operation

specifically, whether a patient has perforated ornonperforated appendicitis.

Shorter period before return to normalactivity,return to work, and return to sports.

There appears to be little benefit to laparoscopicappendectomy over open appendectomy in thin malesbetween the ages of 15 and 45 years. In these

patients, the diagnosis usually is straightforward. Laparoscopic appendectomy may be beneficial in obese

patients, in whom it may be difficult to gain adequateaccess through a small right lower quadrant incision. Inall obese patients in whom the procedure wascompleted laparoscopically the incisions closedprimarily, whereas the wounds closed primarily in only

58% of obese patients who underwent openappendectomy.

There was no difference in rates of wound infectionwhile intra-abdominal abscess rates were not reported.

Diagnostic laparoscopy- advocated as a potentialtool to decrease the number of negative

appendectomies performed. Morbidity associated with laparoscopy and general

anesthesia is acceptable only if pathology requiringsurgical treatment is present and is amenable totreatment using laparoscopic techniques.

The availability of diagnostic laparoscopy may actuallylower the threshold for exploration and thus adversely

impact the negative appendectomy rate.

Fertile women with presumed appendicitis constitutethe group of patients most likely to benefit fromdiagnostic laparoscopy. Up to one third of thesepatients do not have appendicitis atexplorationreduced # of unnecessary appendectomy.

In most of the patients without appendicitis,gynecologic pathology is identified.

It has not been resolved whether laparoscopicappendectomy is more effective in treating acuteappendicitis than the time-proven method of openappendectomy.

It does appear that laparoscopic appendectomy iseffective in the management of acute appendicitis.

Laparoscopic appendectomy should be considered partof the surgical armamentarium available to treat acuteappendicitis.

NATURAL ORIFICE TRANSLUMINAL ENDOSCOPICSURGERY

A new surgical procedure using flexible endoscopes inthe abdominal cavity.

Access is gained by way of organs that are reachedthrough a natural, already-existing external orifice.

The hoped-for advantages associated with this methodinclude the reduction of postoperative wound pain,


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shorter convalescence, avoidance of wound infectionand abdominal-wall hernias, and the absence of scars.

Much work remains to determine if NOTES provides anyadditional advantages over the laparoscopic approach

to appendectomy.

ANTIBIOTICS AS DEFINITIVE THERAPY A study analyzing time to surgery and perforation

demonstrated that risk of rupture is minimal within 36hours of symptom onset. Beyond this point, there is

about a 5% risk of rupture in each ensuing 12-hourperiod. However, in many patients the disease will havean indolent course.

For patients assigned to antibiotic therapy, if symptomsdid not improve within the first 24 hours, anappendectomy was performed.

When patients are treated with antibiotics alone it ispossible that diagnoses of significant pathology such ascarcinoid or carcinoma may be delayed. Because nolaboratory test or clinical investigation can reliablydistinguish patients whose appendicitis is potentiallyamenable to conservative treatment, surgery stillremains the gold standard of care for patients withacute appendicitis.

INTERVAL APPENDECTOMY Treatment of appendicitis associated with apalpable

or radiographically documented mass (abscess orphlegmon)is conservative therapy with intervalappendectomy 6 to 10 weeks later.

Successful and produces much lower morbidity andmortality rates than immediate appendectomy butassociated with greater expense and longerhospitalization time (8 to 13 days vs. 3 to 5 days).

STAGES OF TREATMENT

Initial treatment- consists of IV antibiotics and bowelrest. Although this therapy is generally effective, there

is a 9 to 15% failure rate, with operative interventionrequired at 3 to 5 days after presentation.Percutaneous or operative drainage of abscesses is notconsidered a failure of conservative therapy.

2ndstage of treatment- interval appendectomycarried out. The major argument against interval

appendectomy is that approximately 50% of patientstreated conservatively never develop manifestations ofappendicitis, and those who do generally can be treatednonoperatively.

In addition, pathologic examination of the resectedappendix shows normal findings in 20 to 50% of cases.

Overall, the rate of late failure as a consequence ofacute disease averages 20%.

An additional 14% of patients either continue to have,or redevelop, right lower quadrant pain. Although theappendix may occasionally be pathologically normal,persistent periappendiceal abscesses and adhesions arefound in 80% of patients.

Almost 50% have histologic evidence of inflammation inthe organ itself. Several neoplasms also have beendetected in the resected appendices, even in those ofchildren.

Appendectomy may be required as early as 3 weeksafter conservative therapy. Two thirds of the cases ofrecurrent appendicitis occur within 2 years, and this isthe outside limit.

Interval appendectomy is associated with a morbidityrate of 3% and a hospitalization time of 1 to 3 days.

PROGNOSIS

The mortality from appendicitis in the United States hassteadily decreased from a rate of 9.9 per 100,000 in1939 to 0.2 per 100,000 today.

Factors responsible- advances in anesthesia,antibiotics, IV fluids, and blood products.

Principal factors influencing mortality- whetherrupture occurs before surgical treatment and the age ofthe patient.

The overall mortality rate in acute appendicitis withrupture is approximately 1%.

The mortality rate of appendicitis with rupture in theelderly is approximately 5%a fivefold increase fromthe overall rate.

Death - usually attributable to uncontrolled sepsis,peritonitis, intra-abdominal abscesses, or gram-negative septicemia and pulmonary embolism continuesto account for some deaths.

Morbidity rates- parallel mortality rates and aresignificantly increased by rupture of the appendix and,to a lesser extent, by old age.

Serious early complications- are septic and includeabscess and wound infection.

Wound infection- common but is nearly alwaysconfined to the subcutaneous tissues and respondspromptly to wound drainage, which is accomplished by

reopening the skin incision. It predisposes the patientto wound dehiscence. The type of incision is relevant,complete dehiscence rarely occurs in a McBurneyincision

The sites of predilection for abscesses: Appendiceal fossa Pouch of Douglas Subhepatic space Between loops of intestine - site abscesses are

usually multiple. Transrectal drainage is preferred for an abscess that

bulges into the rectum. Fecal fistula- annoying but not particularly

dangerous, complication of appendectomy that maybe caused by sloughing of the portion of the cecuminside a constricting purse-string suture; by slippingof the ligature off a tied, but not inverted,appendiceal stump; or by necrosis from an abscessencroaching on the cecum.

Intestinal obstruction- initially paralytic butsometimes progressing to mechanical obstruction

may occur with slowly resolving peritonitis withloculated abscesses and exuberant adhesionformation. Late complications are quite uncommon.

Adhesive band intestinal obstruction afterappendectomy does but much less frequently thanafter pelvic surgical therapy.

Inguinal hernia is three times higher in patients whohave had an appendectomy.

Incisional hernia is like wound dehiscence in thatinfection predisposes to it, it rarely occurs in aMcBurney incision, and it is not uncommon in alower right paramedian incision.

CHRONIC APPENDICITIS

Characteristically, the pain lasts longer and is lessintense than that of acute appendicitis but is in thesame location.

There is a much lower incidence of vomiting, butanorexia and occasionally nausea, pain with motion,

and malaise are characteristic. Leukocyte counts are predictably normal and CT scans

are generally nondiagnostic. At operation, surgeons can establish the diagnosis with

94% specificity and 78% sensitivity. There is anexcellent correlation between clinical symptomatology,intraoperative findings, and histologic abnormalities.

Laparoscopy can be used effectively in themanagement of this clinical entity. Appendectomy is

curative. Symptoms resolve postoperatively in 82 to93% of patients. Many of those whose symptoms arenot cured or recur are ultimately diagnosed withCrohn's disease.

APPENDICEAL PARASITES Causes appendicitisAscaris lumbricoides- most common cause. Wide spectrum of helminths have been implicated:

Enterobius vermicularis Strongyloides stercoralis, Echinococcusgranulosis


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The live parasites occlude the appendiceal lumen,causing obstruction.

The presence of parasites in the appendix at operationmakes ligation and stapling of the appendix technically

difficult. Once appendectomy has been performed and the

patient has recovered, therapy with helminthicide isnecessary to clear the remainder of the GI tract.

Amebiasis- can cause appendicitis. Invasion of themucosa by trophozoites of Entamoeba histolytica incites

a marked inflammatory process. Appendicealinvolvement is a component of more generalizedintestinal amebiasis. Appendectomy must be followedby appropriate antiamebic therapy (metronidazole).

INCIDENTAL APPENDECTOMY Decisions regarding the efficacy of incidental

appendectomy should be based on the epidemiology ofappendicitis.

Males were more likely to develop appendicitis thanfemales.

Although incidental appendectomy is generally neitherclinically nor economically appropriate, there are somespecial patient groups in whom it should be performed

during laparotomy or laparoscopy for other indications. These include children about to undergo chemotherapy,

the disabled who cannot describe symptoms or reactnormally to abdominal pain, patients with Crohn'sdisease in whom the cecum is free of macroscopicdisease, and individuals who are about to travel toremote places where there is no access to medical orsurgical care.98

Appendectomy is routinely carried out duringperformance of Ladd's procedure for malrotation,because displacement of the cecum into the left upperquadrant would complicate the diagnosis of subsequentappendicitis.

TUMORS Appendiceal malignancies are extremely rare. Primary appendiceal cancer is diagnosed in 0.9 to 1.4%

of appendectomy specimens. These tumors are only rarely suspected preoperatively.

Fewer than 50% of cases are diagnosed at operation.

Most series report that carcinoid is the most commonappendiceal malignancy, representing >50% of theprimary lesions of the appendix.

A review from the National Cancer Institute'sSurveillance, Epidemiology, and End Results (SEER)program found the age-adjusted incidence ofappendiceal malignancies to be 0.12 cases per

1,000,000 people per year.

Data from the SEER program: mucinous adenocarcinoma- most frequent

histologic diagnosis (38% of totalreported cases) adenocarcinoma- (26%) carcinoid- (17%)goblet cell carcinoma(15%)signet-ring cell carcinoma- (4%)

Five-year survival for appendiceal malignancies variesby tumor type.

Patients with carcinoid tumors have the best 5-yearsurvival (83%), whereas those with signet-ring cellcancers have the lowest (18%).

CARCINOID

Firm, yellow, bulbar mass in the appendix should raisethe suspicion of an appendiceal carcinoid.

The appendix is the most common site of GI carcinoid,followed by the small bowel and then the rectum.

Carcinoid syndrome is rarely associated withappendiceal carcinoid unless widespread metastasesare present, which occur in 2.9% of cases.

Symptoms attributable directly to the carcinoid arerare, although the tumor can occasionally obstruct theappendiceal lumen much like a fecalith and result inacute appendicitis.

The majority of carcinoids are located in the tip of theappendix. They usually present with localized disease(64%).

Tumors


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P 10 f 10

mucus, and careful inspection of the base of theappendix.

Right hemicolectomy or preferably cecectomy-reserved for patients with a positive margin at the

base of the appendix or positive periappendiceallymph nodes.

Recently, a more aggressive approach to rupturedappendiceal neoplasms has been advocated. Thisapproach includes a thorough but minimallyaggressive approach at initial laparotomy with

subsequent referral to a specialized center forconsideration of re-exploration and hyperthermicintraperitoneal chemotherapy.

PSEUDOMYXOMA PERITONEI A rare condition in which diffuse collections of

gelatinous fluid are associated with mucinous implants

on peritoneal surfaces and omentum. Pseudomyxoma is two to three times more common in

females than in males. Recent immunocytologic and molecular studies suggest

that the appendix is the site of origin for theoverwhelming majority of cases of pseudomyxoma.

Pseudomyxoma is invariably caused by neoplasticmucus-secreting cells within the peritoneum that maybe difficult to classify as malignant because they maybe sparse, widely scattered, and have a low-gradecytologic appearance.

Clinical presentation abdominal pain, distention, or a mass. Primary pseudomyxoma usually does not cause

abdominal organ dysfunction. However, ureteralobstruction and obstruction of venous return can beseen

Pseudomyxoma is a disease that progresses slowly andin which recurrences may take years to develop orbecome symptomatic.

Lymph node metastasis and distant metastasis areuncommon.

CT scanning is the preferred imaging modality. At surgery a variable volume of mucinous ascites is

found together with tumor deposits involving the righthemidiaphragm, right retrohepatic space, left paracolicgutter, ligament of Treitz, and the ovaries in women.

Peritoneal surfaces of the bowel are usually free oftumor. Thorough surgical debulking is the mainstay oftreatment.

All gross disease and the omentum should be removed.If not done previously, appendectomy is routinelyperformed.

Hysterectomy with bilateral salpingo-oophorectomy isperformed in women.

Survival is better in patients who undergo R0 or R1resection than in patients who undergo R2 resection(visible gross disease remaining)

Adjuvant intraperitoneal hyperthermicchemotherapy- advocated as a standard adjunct to

radical cytoreductive surgery because 5-year survival ofmucinous appendiceal neoplasms is only 30%.

Cytoreductive surgery with intraperitonealhyperthermica long, tedious procedure withoperative times of 300 to 1020 minutes reported. In addition, morbidity (38%) and mortality (6%) are

high. It is associated with a 5-year survival of

between 53 and 78%. Survival is associated withinitial patient performance status.

Any recurrence should be investigated completely. Recurrences are usually treated by additional

surgery. It is important to note that surgery forrecurrent disease is usually difficult and is associatedwith an increased incidence of unintentionalenterotomies, anastomotic leaks, and fistulas.

LYMPHOMA Extremely uncommon The GI tract is the most frequently involved extranodal

site for non- Hodgkin's lymphoma but other types of

appendiceal lymphoma, such as Burkitt's, as well asleukemia, have also been reported.

Primary lymphoma of the appendix accounts for 1 to3% of GI lymphomas.

Appendiceal lymphoma usually presents as acuteappendicitis and is rarely suspected preoperatively.

Findings on CT scan of an appendiceal diameter 2.5cm or surrounding soft tissue thickening should promptsuspicion of an appendiceal lymphoma.

Appendectomy- The management of when confinedto the appendix

Right hemicolectomy- indicated if tumor extendsbeyond the appendix onto the cecum or mesentery. Apostoperative staging work-up is indicated beforeinitiating adjuvant therapy. Adjuvant therapy is notindicated for lymphoma confined to the appendix.

surgery_1.3 appendix (book).docx

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