acute conditions of the abdomen

7/30/2019 Acute Conditions of the Abdomen

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9Acute Conditions of the Abdomen

David Vo and Samuel Eric WilsonUCI Medical Center, Orange, California

I. UNIQUE ASPECTS IN THE ELDERLY

The acute abdomen can be dened as abdominal pain that necessitates promptassessment, diagnosis, and early treatment, often operative. This emergency isincreasingly common in patients aged 65 and older. First, the elderly representone of the fastest growing segments of the population in North America. Second,not only are people living longer because of advances in medicine, nutrition, andsanitation, but they are also enjoying relatively good health and remaining active.Not unexpectedly, the primary care physician will be confronted with an increas-

ing number of elderly patients complaining of abdominal pain. Diagnosis of acuteconditions of the abdomen in the geriatric patient is a major challenge becauseof its protean manifestations and diverse causes. This chapter will review thediagnosis and treatment of conditions specic to acute conditions of the abdomenin the older patient.

Delay in diagnosis may contribute to the signicantly higher morbidity andmortality rates found in elderly patients with acute abdominal emergencies. Froman analysis of three large series of patients, Telfer et al. conrmed that a highermortality in older patients was associated with a lower diagnostic accuracy com-pared with that of younger patients (1). They also noted that the causes of acuteabdominal diseases differed in older patients compared with younger age groups.Recognition of the different causes would likely expedite diagnosis of abdominalemergencies in elderly patients (Table 1). Patients older than 50 years of agewith a chief complaint of abdominal pain most commonly had acute cholecystitis,whereas younger patients were more likely to have nonspecic abdominal painor appendicitis. In addition, bowel obstruction and pancreatitis were about fourtimes more common in older patients. Cancer, especially adenocarcinoma of the

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Table 1 Rates of Disease in 2406 Patients 50 Years Old and 6317Patients 50 Years Old Initially Seen with Acute Abdominal Pain fromthe OMGE a Series b

% younger than 50 % older than 50Disease (6317 total) (2406 total)

Nonspecic abdominal pain 39.5 15.7Appendicitis 32.0 15.2Cholecystitis 6.3 20.9Obstruction 2.5 12.3Pancreatitis 1.6 7.3Diverticular disease 0.1 5.5Cancer 0.1 4.1

Hernia 0.1 3.1Vascular 0.1 2.3

a World Organization of Gastroenterology (OMGE) Research Committee Multi-National Survey.

b From Ref. 1.

colon and rectum, mesenteric ischemia, and diverticular complications were moretypical in the geriatric patient. Vascular causes initially seen as an upper abdomi-nal pain syndrome included mesenteric arterial ischemia, embolus, myocardialinfarction, and symptomatic abdominal aortic aneurysm.

Additional factors complicate the diagnosis of acute conditions of the abdo-

men in the elderly patient. The history may be inadequate because of mentalconfusion or underlying dementia, and co-existing illnesses can be distractingvariables. Signs of peritonitis may be attenuated, with guarding being less pro-nounced because of a thinned abdominal musculature. Temperature elevation canbe dampened to the point of hypothermia, and the white blood cell count tendsto respond less vigorously. The use of nonsteroidal anti-inammatory drugs (e.g.,for arthritis) is more prevalent in the older patient and can mask abdominal pain.Seeking medical care may be delayed, leading to more advanced disease at pre-sentation. Social factors such as living alone or fear of being institutionalized,losing ones independence, attributing symptoms to constipation and indigestion,or nancial concerns may cause elderly people to avoid seeking medical attentionearly.

Elective surgery is generally well tolerated in the t geriatric patient withminimal increase in morbidity and mortality compared with younger patients.However, in an emergency situation, the risks increase dramatically for olderpatients, in part because of a decrease in physiological reserves, an impairedimmune response to infections, and a high incidence of chronic cardiopulmonary


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Acute Conditions of the Abdomen 143

diseases associated with advancing age. Early surgery for most geriatric abdomi-nal emergencies is the goal, but adequate time should be allowed for appropriatestudies and preoperative preparation. (See Chapters 5 and 6.) Diagnostic explor-atory laparoscopy has recently been suggested as having a potential role in theassessment of abdominal pain, thus abbreviating extensive preoperative studies(2). Important perioperative principles include optimization of associated medicalconditions, timely but judicious replacement of uids and electrolytes, aggressiverespiratory care to prevent atelectasis and pneumonia, and early mobilization toavoid deep venous thrombosis and pulmonary embolism. The simplest operationthat will do most to correct the immediate problem should be the goal whenperforming emergency abdominal surgery in the geriatric patient. One-stage de-nitive procedures should be attempted whenever safe and stomas avoided if

feasible.

II. ACUTE CHOLECYSTITIS

A. Clinical Relevance

Acute cholecystitis is one of the most common abdominal illnesses that requiresurgical intervention in elderly people. The incidence of cholelithiasis increaseswith age in North Americans, ranging from 25% to 40% for those in their 60sto more than 50% in those 70 years of age and older (3). Biliary tract diseaseshould be considered prominently in the differential diagnosis of acute upperabdominal pain in the geriatric population. In most cases, acute cholecystitis re-sults from obstruction of the cystic duct by an impacted gallstone. Steady and

persistent epigastric or right subcostal abdominal pain that may radiate to theback or to the tip of the right scapula is the most common complaint. Nausea,vomiting, fever, and chills may follow. A history of known gallstones, prior at-tacks of similar pain, or occasionally pancreatitis can be elicited in most cases.Physical ndings are most remarkable for right upper quadrant abdominal tender-ness with or without fever, jaundice, and a palpable right upper quadrant abdomi-nal mass in about a third of the cases. Laboratory studies will reveal an elevatedleukocyte count. Major complications are empyema, gangrene, and perforationof the gallbladder. A pericholecystic abscess should be suspected when the patientappears toxic with high fever and leukocyte count. Free perforation occurs infre-quently and manifests as sudden spreading of previous localized pain and tender-ness.

B. Immediate Diagnostic Approach

Acute cholecystitis should be strongly suspected if a tender, palpable gallbladderis present together with the preceding history. The rst diagnostic study is abdom-


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inal ultrasonography, which is highly sensitive in showing gallstones in morethan 95% of cases. Findings of gallstones, dilated and thickened gallbladder wall,pericholecystic uid, and an ultrasonographic Murphys sign are all suggestive of acute cholecystitis. If the ultrasonogram is equivocal, a technetium 99m-labeledderivative of iminodiacetic acid (e.g., HIDA) scan should be performed. Afterintravenous injection of the radionuclide, imaging of the bile ducts and gallblad-der normally appears within 15 to 30 minutes and of the small intestine within60 minutes. Failure to visualize the gallbladder while contrast appears in thecommon bile duct or duodenum indicates cystic duct obstruction.

Elderly patients differ in that they are initially seen with more advancedstages of biliary disease. Secondary complications such as jaundice caused bycommon bile duct (CBD) stones, cholangitis, empyema, gangrene, free perfora-

tion, and subphrenic or liver abscesses are all more common in the older agegroup (4). Clinical ndings may be deceptively benign despite severe underlyingpathological conditions, leading to a delay in diagnosis and poorer outcomes.Morrow et al. found that abdominal tenderness, peritoneal signs, temperatureelevation, and leukocytosis can be absent in about 26%, 50%, 38%, and 35% of elderly patients with acute cholecystitis, respectively (5). In addition, the inci-dence of CBD stones increases with age and occurs in about 20% of patients 65years and older with acute cholecystitis. CBD stones should be suspected in thosewith severe gallstone pancreatitis, a bilirubin value 3 mg/dL, a dilated CBDor stones seen in the CBD on ultrasonography.

Acute suppurative cholangitis is a serious complication of stones in theCBD. Right upper quadrant abdominal pain, jaundice, fever, and chills, knownas Charcots triad, may be absent in 30% of patients with cholangitis. Leukocyte

count and alkaline phosphatase levels are usually elevated. Mental confusion andhypotension in the presence of Charcots triad indicate sepsis from ascendingcholangitis (Reynolds pentad) and may be the initial presenting symptoms inthe older patient. Emergency decompression of the CBD and intravenous antibi-otics are required. Endoscopic retrograde cholangiopancreatography (ERCP)with sphincterotomy has been reported to be successful in removing CBD stonesover 90% of the time (6).

C. Therapeutic Intervention

Elective cholecystectomy should be strongly considered for symptomatic choleli-thiasis before the development of complications. Elective biliary surgery in theelderly patient, including laparoscopic cholecystectomy, is safer and associatedwith reduced postoperative morbidity and mortality compared with emergencysurgery. Most deaths from acute cholecystitis occur in patients older than 60 orthose with diabetes mellitus. Emergency cholecystectomy in the elderly has areported mortality rate of about 10%. The major causes of death postoperatively


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are due to sepsis and resultant multisystem organ failure, heart failure, pneumo-nia, and pulmonary embolus (7). Morrow et al. showed that medical therapyfailed for most elderly patients with acute cholecystitis (5). Resuscitation con-sisting of hydration, nasogastric decompression, and intravenous antibioticsshould be followed by prompt operation. Early cholecystectomy is the denitivetreatment for acute cholecystitis in the elderly and is associated with decreasedmorbidity and mortality compared with medical management followed by elec-tive cholecystectomy at a later date (8). In addition, early surgery will avoidoverlooked diagnoses from other causes such as perforated duodenal ulcer orappendicitis and recurrent attacks of cholecystitis during a waiting period. Giventhe increased incidence of CBD stones in the older patient, the routine use of intraoperative cholangiography is encouraged. If stones are discovered, they may

be removed intraoperatively or alternatively by ERCP with sphincterotomy post-operatively.An initial approach with laparoscopic cholecystectomy is safe and effective

in many young and elderly patients with acute cholecystitis. However, older pa-tients have greater risk for conversion to open cholecystectomy than youngerpatients and the rate can be as high as 50% (9). The operative duration, analgesicrequirement, recovery and hospitalization times, and postoperative complicationswere all increased in those requiring conversions to open surgery in the elderlygroup. A planned open cholecystectomy or early conversion from a laparoscopiccholecystectomy if severe adhesions are encountered should be considered incritically ill elderly patients (10).

When cholecystectomy is contraindicated because of the patients criticalcondition or it is deemed technically dangerous, cholecystostomy should be con-

sidered as an alternative. A drainage tube is placed in the dome of the gallbladderthrough a limited incision performed with the patient under general or local anes-thesia or by image-guided percutaneous cathether placement. It is important toensure there is no co-existing cholangitis. After resolution of the crisis, an electiveinterval cholecystectomy should be performed if stones are present versus simpleremoval of the drainage tube if no stones are detected by cholangiogram (11).

III. ACUTE APPENDICITIS


The diagnosis of acute appendicitis still rests primarily on clinical assessment.Acute appendicitis should not be disregarded as a possible cause of abdominalpain in patients older than 50 because appendicitis accounts for approximately15% of all abdominal emergencies in this older age group (1). Advancing ageis associated with increasing morbidity and mortality in patients with acute ap-pendicitis. Although the elderly group accounts for only 5% to 10% of all cases


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of appendicitis, about half of the fatalities from appendicitis occur in this agegroup (12). The mortality rate of 0.8% to 1.6% in the general population contrastssharply with that of approximately 10% and greater in those older than 70 (13,14). These deaths are primarily related to the septic complications arising fromperforated appendicitis. Prompt diagnosis followed by surgery, before the devel-opment of gangrene, perforation, or abscess formation, is crucial in reducing theincreased morbidity and mortality observed in the older patient.


The clinical presentation of acute appendicitis is often thought to be atypical inthe older person, but some recent studies suggest that the clinical features of

appendicitis in the elderly are similar to those in the younger population (15, 16).Right lower quadrant abdominal pain and tenderness were the most commonndings. Associated nausea, vomiting, fever, chills, anorexia, and leukocytosiswith increased immature cells were not infrequent. Vague pain that moves fromthe periumbilical area to localize in the right lower quadrant, is exacerbated bymovement, and occurs with focal right lower quadrant tenderness, guarding, andrebound should all favor acute appendicitis. However, the elderly patient willusually not have all these classical ndings in a clear-cut fashion. In one series,only 20% of elderly patients with appendicitis had all the following ndings:nausea or vomiting, fever, right lower quadrant tenderness, and an elevated whiteblood cell count (WBC) or left shift of the WBC (high percentage of neutrophilsand band forms) (16). In addition, the symptoms and signs of appendicitis areoften similar to other disease processes that are more common in the older age

groups, leading to signicantly higher errors in diagnosis. Common misdiagnosesin the older patient include diverticulitis, bowel obstruction, carcinoma, acutecholecystitis, or even ruptured abdominal aortic aneurysm. Diagnostic studiesmay often obscure the diagnosis, such as elevated bilirubin levels suggestinghepatobiliary disease, and roentgenograms showing ileus, bowel obstruction, orincidental nephrolithiasis or cholelithiasis.

The elderly patient is more likely to have complications. Franz et al. foundthat 91% of their patients older than 50 had either perforated appendicitis or anassociated intra-abdominal abscess compared with only 25% in patients less than50 years old (17). Those older than 70 carried the greatest risk of having perfora-ted appendicitis associated with an intra-abdominal abscess. This is compatiblewith other studies, showing that the risk of gangrene and perforation are abouttwo to four times more likely in patients older than 50 (4, 18, 19). The symptomsand signs in older patients may alert the clinician to the severity of the underlyingpathological condition (Table 2). Franz et al. also found that prolonged durationof symptoms before presentation to the hospital correlated strongly with the inci-dence of complications and nal outcome (17). Those with simple appendicitis


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Table 2 Differences in Presentation of Acute Appendicitis in 366Patients 50 Years Old and 1970 Patients 50 Years Old from theOMGE a Series b

% of patients % of patientsClinical feature 50 yr old 50 yr old

Generalized pain 2.2 13.1Pain duration 24 hr 57.2 75.4Previous surgery 3.2 21.0Distention 6.2 23.8Generalized tenderness 2.1 14.2Rigidity 18.9 40.1Decreased bowel sounds 19.0 38.0

Mass 4.0 12.1a World Organization of Gastroenterology.b From Ref. 1.

complained of symptoms lasting less than 24 hours, whereas those who had pro-gressed to rupture or abscess experienced symptoms for more than 48 hours. Inaddition, Thorbjarnarson and Loehr postulated that anatomical changes in theappendix associated with aging could lead to earlier perforation (18). Thesechanges include narrowing of the appendiceal lumen, thinning of its mucosa, anda decrease in the number of lymphocytes, all of which result in a structurallyweakened appendix with decrease vascularity.


Given all these factors, early diagnosis within 24 hours of symptom onset andprompt appendectomy before development of gangrene and perforation are cru-cial in reducing the morbidity and mortality of acute appendicitis in the olderpatient. A computer tomographic scan of the abdomen may be obtained to look for focal fat stranding, small bowel thickening, or abscess in the right lowerquadrant. Diagnostic laparoscopy may be considered in very ill elderly patientswith an unclear diagnosis to exclude acute appendicitis and other life-threateningconditions (20). This could avoid untimely delays from extensive diagnostic stud-ies. If appendicitis is found, a laparoscopic appendectomy may be performed atthe same time. (The cecum should be examined intraoperatively and the pathol-ogy reviewed to ensure that a primary appendiceal malignancy was not the causeof acute appendicitis.) The role of the surgeon in the management of the acuteabdomen resulting from appendicitis in the elderly patient is to expedite diagnosisand proceed with appendectomy, while acknowledging a negative laparotomyrate in exchange for decreasing the rate of perforation and gangrene.


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IV. INTESTINAL OBSTRUCTION


Adhesions, malignant disease, and incarcerated hernias account for most intesti-nal obstruction in industrialized nations. The peak incidence for each occurs inthe eighth decade of life. Obstruction caused by postoperative adhesions has be-come the most common cause, but strangulated hernias and intra-abdominal ma-lignancies, particularly colorectal cancer, still account for 50% of all cases anddeaths. Colon cancer may present with large bowel obstruction manifesting asearly abdominal distention and constipation, followed by pain and vomiting atlater stages. However, small bowel obstruction (SBO) can be more prominent if the ileocecal valve is incontinent.


Diagnosis of SBO is made on the basis of colicky abdominal pain, nausea, vom-iting, diffuse abdominal tenderness, and distention. Although some controversyis acknowledged regarding the optimal timing of operation for small bowel ob-struction, it is agreed that urgent surgery is required if peritoneal signs are present,indicating strangulation. The accepted criteria for strangulation may not be accu-rate in elderly patients (21). Approximately one-third of elderly patients withstrangulation obstruction will display minimal symptoms or signs of ischemicbowel preoperatively. Leukocytosis and tachycardia are noted most consistently,whereas presence of an abdominal mass, change in the nature of pain from inter-mittent to constant, localized tenderness, fever, shock, and bloody diarrhea oc-

curred less reliably. The use of computed tomography (CT) scans of the abdomenmay increase the detection of strangulation obstruction. CT ndings of poor en-hancement of bowel wall, a serrated beak, ascites, and engorgement of mesentericveins are suggestive of strangulated obstructions (22).


It is recommended that elderly patients with complete SBO be operated on within24 hours because delay carries a high risk of increased morbidity and mortality(23). Mortality rates escalate from 3% for simple obstructions to 30% when thebowel becomes necrotic or perforated (24). The presence of a malignancy is asignicant risk factor for mortality in the elderly patient. The currently acceptedindications for selective conservative management of SBO include carcinomato-sis, Crohns disease, early postoperative obstruction, and partial SBO. In the ab-sence of these specic conditions, surgery should be performed expeditiously inelderly patients to avoid the sequelae of unrecognized strangulated obstruction.In addition, other studies have shown that a signicant increase in the complica-


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tion rate and mean length of hospital stay exists for those who received delayedoperation versus early operation within 48 hours. Wound infection is the mostcommon postoperative complication and has been shown to be related to thenumber of enterotomies made (21). Delayed wound closure should be consideredin patients operated on for SBO after having an enterotomy because of the sig-nicant increased risk of wound infection despite appropriate prophylactic antibi-otics.

D. Specic Causes of Intestinal Obstruction

1. Postoperative Adhesions

Postoperative adhesions are the leading cause of small intestinal obstruction, ac-counting for more than 40% of all cases and 60% to 70% of those involving thesmall bowel (25). Intestinal obstruction caused by adhesion is likely to increaseas the numbers of major elective abdominal operations in the geriatric populationincreases. Laparoscopy does not seem to eliminate the risk of adhesions andobstruction. A high risk of recurrence is present after operative relief for obstruc-tions caused by adhesions. Some patients who have had repeated operations forSBO may develop a frozen abdomen, in which adhesions are so dense thatthe bowel becomes xed and is unable to achieve the degree of torsion necessaryfor strangulation. In these patients, a trial of nasogastric or small bowel decom-pression is warranted.

2. Strangulated Hernias

Elderly patients account for most of those presenting with obstruction caused bystrangulated hernias, with the peak age occurring in the seventh and eighth de-cades. Abdominal wall hernias usually present little diagnostic challenge, buthernias are often neglected by the patient who views it as a nuisance and by theprimary care physician who may erroneously consider the patient too frail toundergo an operation. The surgeon may also overlook the diagnosis of incarcer-ated hernia in an elderly patient by failing to examine the inguinal orices. Elec-tive hernia repair is well tolerated in the geriatric group, whereas emergencyrepair for incarceration is associated with excessive morbidity and mortality thatcan climb as high as 55% and 15%, respectively (26). Factors associated withincrease risk of groin hernia incarceration include advanced age, femoral morethan inguinal location, and recent appearance of the mass.

The obturator hernia is a rare and usually overlooked cause of intestinalobstruction in the older patient. There is a 7:1 ratio of women versus men af-fected. The classical patient is an elderly emaciated woman with chronic medicalillnesses presenting with recurrent abdominal pain or partial intestinal obstructionand no history of previous abdominal operations. Most are residents of nursing


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homes or chronic care hospitals. A palpable groin mass is absent in most cases.Any patient with the aforementioned prole who is suspected of having a bowelobstruction should undergo a prompt CT scan to diagnose internal herniation.However, diagnosis continues to be delayed in these debilitated patients and oftenis made only at laparotomy, where bowel resection is required in about 75% of cases (27). This reects the high morbidity and mortality rates of 65% and 25%,respectively.

3. Volvulus

Several other causes of intestinal obstruction are unique to the geriatric patient,including sigmoid and colonic volvulus. Sigmoid volvulus often occurs in elderlypersons residing in institutions who have multiple co-existing diseases. Patients

usually have abdominal pain, distention, and constipation, and it is correctly diag-nosed only in about 60% of patients. A history of recurrent minor attacks maybe present. Features suggestive of subclinical volvulus are recurrent abdominalpains, distention, and constipation relieved by a dramatic passage of atus. Plainabdominal reoentgenograms characteristically display a dilated sigmoid loop witha birds beak narrowing. Conservative treatment with endoscopic decompres-sion and rectal tube placement is indicated in the absence of peritoneal signs.Endoscopic treatment has a high success rate but is associated with frequent re-currences. Endoscopic decompression should be followed by elective sigmoidresection during the same hospital stay in otherwise healthy patients because therisk of recurrence is high with nonoperative treatment, and emergency surgeryhas a 30% mortality rate versus 5.6% for elective resection (28). Resection of redundant colon and creation of an end colostomy should be considered in pa-tients with sigmoid volvulus who are bedridden or incontinent of stool and wouldnot benet from maintenance of bowel continuity.

4. Colonic Pseudo-Obstruction

Colonic pseudo-obstruction, also known as Ogilvies syndrome, occurs generallyin elderly, bedridden patients with chronic disease who are receiving polyphar-macy. Gangrene, infarction, and perforation may ensue as colon diameter in-creases and particularly if cecal distention reaches greater than 12 cm. Mortalityapproaches nearly 50% when perforation and gangrene occur. Colonoscopic de-compression is the treatment of choice. If this fails, surgical decompression maytake the form of cecostomy or may require exteriorization or resection of thecolon if infarction has occurred (29).

5. Gallstone Ileus

Gallstone ileus is characterized by mechanical SBO caused by the passage of alarge biliary calculus from the gallbladder to the duodenum through a stula.


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The insidious clinical presentation and the lack of specic signs of biliary diseaseare responsible for the delayed preoperative diagnosis that leads to an overallmortality rate of 15%. Signs of Riglers triad: small bowel obstruction, ectopicgallstones, and air in the biliary tree are virtually diagnostic. Plain lms, ultraso-nography, or CT scan may help establish the diagnosis by detecting the obstruc-tion. Operative intervention consists of simple enterolithotomy that is associatedwith an operative mortality of 12% and a recurrence of less than 5% (30). Othersmay advocate a one-stage procedure consisting of removal of the impacted gall-stone, stula repair, and cholecystectomy for low-risk patients despite a slightlyhigher operative mortality of about 17% (31).

V. ACUTE MESENTERIC INFARCTIONA. Clinical Relevance

The rst description of acute intestinal infarction was reported by Antonio Beni-vene from Florence in the latter fteenth century. Today, the exact incidence of intestinal ischemia is difcult to assess, but some studies estimate it to be 0.1%of all patients referred to a hospital and 1% of all patients initially seen with anacute condition of the abdomen. In the 1930s to 1960s, the reported mortalityrates varied from 70% to 90%; this has changed little from recent rates of 45%to 90%. Reasons contributing to these high mortality rates may be late diagnosisleading to intestinal infarction and gangrene, continued unrecognized bowel isch-emia even after correction of the underlying cause, and an increasing incidenceof patients with nonocclusive mesenteric ischemia. The pathophysiological

changes of intestinal ischemia range from reversible alterations to transmuralhemorrhagic necrosis of all or part of the small intestine and right half of thecolon. Segmental ischemic colitis of the sigmoid colon represents another variantof mesenteric ischemia.

Arterial causes of acute mesenteric ischemia include superior mesentericartery (SMA) embolus or thrombosis and nonocclusive mesenteric ischemia.SMA embolus accounts for 40% to 50% of cases and is usually caused by emboli-zation of a left atrial or ventricular mural thrombus after a period of cardiacdysrhythmia or infarction. A history of peripheral artery embolism and synchro-nous arterial emboli should be sought. SMA thrombosis contributes to 25% of cases. The acute thrombosis is usually due to progressive atherosclerotic stenosisat the origin of the SMA, until eventually complete occlusion occurs. Symptomsof chronic mesenteric ischemia can be ascertained in 20% to 50% of patients.Coronary artery, cerebrovascular, and peripheral vascular diseases are inevitablypresent. An aortogram will reveal occlusion of the superior mesenteric arterynear its origin and usually a concomitant obstructive lesion of the celiac axis.

A venous cause represents the least common cause of acute mesenteric


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ischemia and is primarily due to mesenteric venous thrombosis. It is usually asso-ciated with a hypercoagulable state, abdominal trauma, portal hypertension, pan-creatitis, viscus perforation, intra-abdominal sepsis, and cancer. Diagnosis ismade with CT or MRI scan.

Nonocclusive mesenteric ischemia (NOMI) is a more common cause of acute mensenteric ischemia than previously recognized, although the true inci-dence remains unknown. Earlier studies suggested that it accounted for 20% to30% of acute mesenteric ischemia cases. In a recent series, Newman et al. docu-mented an increased incidence of 47%, and when SBO was excluded as a cause,this gure rose to 58% (32). This incidence compares similarly to that reportedby Ottinger and Austen of 50% (33). Furthermore, patients diagnosed with NOMIcarried the highest mortality rate compared with the other causes. NOMI is caused

by prolonged splanchnic vasoconstriction occurring usually in the clinical settingof tissue hypoperfusion, decreased cardiac output, and hypotension. Precipitatingfactors include atrial brillation, myocardial infarction, congestive heart failure,aortic insufciency, hypovolemia, sepsis, and cardiopulmonary bypass. Digoxintoxicity, vasopressors, and cocaine use may cause mesenteric vasoconstriction.Patients on high-ow hemodialysis have also developed this syndrome. Diagnosisis made on the basis of clinical suspicion and angiographic ndings that con-sist of patent mesenteric vessels with segmental vascular spasms mimickingchain of sausages in the origins of multiple branches of the SMA, pinchingoff of the intestinal branches, spasm of the arcades, and impaired lling of intramural vessels. It is important to realize that intestinal ischemia may not mani-fest until hours or days after the precipitating event, and vasospasm may persisteven after the initial cause is corrected (34).


The clinical characteristics of intestinal ischemia consist of acute onset of severeabdominal pain that is out of proportion to ndings on physical examination, aforceful episode of bowel evacuation, and bloody diarrhea. Decompensation mayoccur acutely over hours or insidiously over days. Risk factors associated withacute intestinal ischemia include age 50 years, atherosclerotic cardiac and pe-ripheral vascular diseases, history of intestinal angina, hypertension, critically illpostoperative patients, and the presence of multiple comorbidities. Newman etal. found that a high proportion of mesenteric infarction developed in patientswho were already hospitalized and being treated for a different illness (32). Thiswas particularly evidenced by patients with a prolonged intensive care course,those being treated with digoxin or vasopressors, and postoperative cardiovascu-lar patients. Intestinal ischemia may manifest in these critically ill patients assystemic sepsis or multiple organ failure. A nonspecic abdominal examinationis not uncommon early in course of ischemia. Unexplained abdominal distention,


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gastrointestinal bleeding, or mental confusion may be the only early signs of acute intestinal ischemia in the elderly patient. Increasing abdominal tenderness,rebound, guarding, distention, bloody diarrhea, and shock are highly suspiciousfor infarcted bowel. In addition, laboratory studies may reveal leukocytosis witha left shift, hemoconcentration, elevated alkaline phosphatase, metabolic acidosiswith an increased base decit, increased serum lactate level, hyperamylasemia,and hyperphosphatemia. Of these tests only an elevated serum lactate level maybe a predictor of mortality. As with clinical ndings, plain lms of the abdomenare generally unremarkable in early ischemia. However, later in the course of the disease dilated and gasless loops of small intestine containing air-uid levels,thumb printing of the bowel wall, intramural or portal venous gas, and freeintraperitoneal air or uid can be seen (35).

Early diagnosis of acute mesenteric ischemia is usually not apparent on thebasis of clinical and biochemical assessments alone. The history is often incom-plete as a result of the debilitated nature of these patients, and abdominal painand tenderness may be absent in approximately 25% to 30% of cases. By thetime ndings become evident there has already been severe progression to nonvi-ability of the involved bowel. CT of the abdomen and selective mesenteric angi-ography may assist in establishing a diagnosis earlier in the course of the disease,but so far these diagnostic studies have had little impact on the overall mortality.The main usefulness of CT lies in its ability to exclude other abdominal pathologi-cal conditions in a fast and noninvasive manner. Although CT is sensitive forthe evaluation of intestinal ischemia, the ndings are not specic (22). Bowelwall thickening is the most common CT nding that reects submucosal edemaand hemorrhage. Luminal dilation may be seen and reects ileus in the ischemic

segments. Fluid-lled bowel loops containing minimal intraluminal gas are dueto exudation of blood and uid into the lumen. The mesenteric fat may haveincreased attenuation because of edema. Intramural gas or pneumatosis intesti-nalis is observed in only 4% to 16% of proven bowel ischemia and is causedby dissection of luminal gas into the bowel wall across the compromised mucosa.Mesenteric or portal venous gas is even more infrequent and represents escapeof intramural gas into the mesenteric venous system. Obviously, free intraperito-neal air and uid indicate perforation and peritonitis. CT is the study of choicefor evaluating mesenteric venous thrombosis and may also detect SMA throm-bosis.


An aggressive roentgenological and surgical approach to mesenteric ischemiaproposed by Boley et al. has been reported to reduce mortality to 50% to 60%if delay is less than 12 hours (36). The premises are based on a high clinicalsuspicion in any atherosclerotic elderly patient with vague abdominal pain and


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early use of angiography. Initial treatment consists of resuscitation, restora-tion and monitoring of cardiac output with a pulmonary artery catheter, and dis-continuation of digitalis or vasopressors. Broad-spectrum antibiotics arewarranted as a result of intraluminal bacterial translocation across the ischemicwall. A mesenteric angiogram should be obtained expeditiously if the CT is unre-markable or shows signs of ischemia. Aggressive and early use of angiographywill result in a large number of negative studies, but it is the most precise methodfor diagnosing both occlusive and nonocclusive intestinal ischemia (36). Me-senteric arterial vasospasm is often present and may continue for several dayseven after correction of the underlying cause. If mesenteric vasoconstriction ispresent on the angiogram, papaverine infusion through an SMA catheter may betried.

Persistent peritoneal signs usually occur in the presence of infarcted boweland are an indication to proceed with an explorative laparotomy. Goals wouldbe to restore intestinal arterial ow, resect irreparably damaged bowel, or both.In some cases, revascularization should precede resection of questionable viablebowel segments because surprising recovery may occur after restoration of bloodow. Techniques for assessment of bowel viability include clinical criteria, Dopp-ler ultrasonography, and uorescein injection. Questionable segments of viablebowel can be left intact and reassessed at second exploration planned within 12to 24 hours. Transarterial embolectomy can be performed for SMA embolus, andheparin may be instituted for prophylaxis against further emboli. SMA thrombo-sis may be revascularized by bypass or transaortic SMA endarterectomy. If gan-grenous bowel is present as a result of NOMI, the surgeon may favor performinga delayed anastomosis with stoma until perfusion is adequate to maintain an anas-

tomosis (37). Thrombolytic therapy has yet proven to have a signicant role inthis disease.

Recognition of chronic visceral ischemia may permit elective revasculari-zation before the development of acute mesenteric infarction. Atherosclerotic nar-rowing of the mesenteric arteries accounts for about 95% of cases, and usuallyinvolvement of at least two major arteries is required to produce symptoms.Symptomatic patients usually have dull and gnawing periumbilcial or epigastricabdominal pain. Intestinal angina begins between 15 and 30 minutes after mealsand may persist for several hours. As the occlusion worsens, the angina will bebrought on by smaller amounts of food until the patient develops a fear of eat-ing. This eventually leads to weight loss. The ratio of women to men is 3:1. Ahistory of coronary artery, cerebrovascular, and peripheral vascular diseases isnot uncommon, and an epigastric bruit may be heard on examination. Diagnosisdepends on a high index of suspicion in any elderly patient with postpran-dial abdominal pain, food aversion, and weight loss (38). This should promptan arteriogram followed by surgical revascularization if results are conrm-atory.


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VI. COLORECTAL CANCER


Intra-abdominal cancer should be a consideration in every elderly patient withabdominal pain, particularly if the pain is nonspecic, associated with weightloss, and the diagnosis is not immediately obvious. Colorectal cancer accountsfor most intra-abdominal cancers in North America, with the incidence estimatedto be about 150,000 cases per year. It is the second leading cause of cancer deathsin Western countries. Adenocarcinomas account for 95% of the malignant tumorsin the colon and rectum. The geriatric patient is primarily affected, with approxi-mately two-thirds to three-quarters of the incident cases occurring in those 65years of age or older. The age-adjusted colorectal cancer incidence rate for per-

sons 65 years and older is 20 times greater than the rate for those younger. About40% of these patients will initially be seen with advanced disease. Other knownrisk factors include a low-ber, high-fat diet, hereditary polyposis syndromes,long-standing inammatory bowel disease, adenomatous polyps, previous colo-rectal cancer, and a family history of colorectal cancer.

The pathogenesis of colorectal carcinoma represents a multistep processwith a mean doubling time of 130 days. This translates to about 10 years of silentgrowth before a cancer reaches signicant size to produce symptoms. During thisasymptomatic period, screening is necessary to detect early curable lesions. Stud-ies have suggested a reduced mortality from colorectal cancer by screeningasymptomatic individuals over the age of 50 (39, 40). Patients with additionalrisk factors as previously mentioned should undergo earlier and more frequentscreening examinations. Detection of cancers at earlier stages and removal of

premalignant adenomatous polyps explain the basis for mortality reduction (41).Fecal occult blood tests or exible sigmoidoscopy are currently recommendedfor the screening of asymptomatic elderly persons. Fecal occult blood testing hasbeen shown to be effective in detecting cancers at earlier and more curable stagesthan unscreened groups, and mortality has been shown to be reduced in screenedversus control populations. Screening sigmoidoscopy is also thought to reducecolorectal cancer mortality. If the fecal blood test is positive or adenomatouspolyps are found on sigmoidoscopy, full colonoscopy is indicated. Nonspecicabdominal pain in the elderly patient should prompt an appropriate evaluation,such as barium enema, colonoscopy, or CT of the abdomen, to exclude cancer.


Colorectal cancer commonly presents in an insidious manner with an averagedelay between onset of symptoms and denitive treatment of 7 to 9 months.Any complaints of change in bowel function should raise suspicion for colorectalcarcinoma. The elderly patient may be experiencing multiple chronic illnesses,


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156 Vo and Wilson

which may cause the patient to attribute some disturbance of bowel function tothese disorders. Symptoms and signs that are clues to the diagnosis of colorectalcancer include iron deciency anemia, lower gastrointestinal bleeding, vague ab-dominal pain, tenesmus, mucous diarrhea, unexplained weight loss, fatigability,presence of an abdominal mass, and abdominal distention. Clinical ndings usu-ally correlate with the tumors anatomical location. Right-sided lesions tend togrow as large polypoid fungating masses that produce minimal obstructivechanges resulting from the uid content of feces and large diameter of bowelwall in this location. Patients complain of fatigue and weakness because of irondeciency anemia from occult blood loss in the stool, vague right lower abdomi-nal discomfort, and, not infrequently, a palpable mass. Bowel obstruction causedby cecal carcinoma is uncommon, but it should be suspected in any elderly patient

with distal small bowel obstruction because of its associated poor survival (42).In contrast, left-sided colon cancers grow in an annular fashion, producing anapkin-ring constriction. Alterations of bowel function are common and areattributed to the smaller caliber of the left colon and semisolid nature of feces.Gradual occlusion of the bowel occurs and is manifested by alternating constipa-tion and diarrhea, narrowing of stools, and occasionally mild mucous bleedingmixed with stool. Cancer in the rectum produces bright red blood usually inassociation with defecation and tenesmus. Even in the presence of hemorrhoids,cancer must be excluded in the elderly patient with rectal bleeding.

Additional evaluation should include a complete blood count, liver en-zymes, carcinoembryonic antigen level, and chest lm. Colonoscopy aides inobtaining a pathological diagnosis, and CT will help evaluate for lymphadenopa-thy and metastatic disease. Endorectal ultrasonographic scanning should be ob-

tained for local staging of rectal carcinomas.


The only possible curative treatment for colorectal cancer is surgical resection.Various studies have shown that elective surgical resection is well tolerated inelderly patients (43, 44). This involves en bloc removal of the tumor with 10-cmproximal and 2-cm distal margins, along with complete resection of the involvedlymphatic nodal basin. Resection of limited and accessible hepatic metastaseshas been shown to improve survival with minimal adverse effects. Cryosurgeryand intraoperative ultrasonography show promise in this eld. Solitary pulmonarymetastases should also be considered for resection (45). Surgery is also indicatedfor palliation of large tumors that may obstruct, perforate, or bleed.

Colorectal cancers that present with obstruction or peritonitis caused byperforation require emergency surgery. Prognosis is poorest for this group of patients, with mortality rates ranging from 16% to 48%. Presence of multiplecomorbidities increases the mortality. Long-term survival is decreased even after


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successful radical resection in the emergency versus elective groups. In addition,tumors tend to be more advanced and metastases more common in the emergencygroup (46). The minimal operation, such as bypass or diversion, should bestrongly considered for the critically ill elderly patient with multiple cormorbidi-ties presenting with an emergency complication. A staged resection can be at-tempted after recovery from the acute stress under optimized conditions (47).

VII. PEPTIC ULCER DISEASE


The incidence and prevalence of peptic ulcer disease (PUD) have declined over

the past several decades and may be related to the introduction of histamine H 2-receptor antagonists and proton pump inhibitors in the 1970s. This has correlatedwith a decline in elective surgical intervention for PUD. However, the numberof emergency operations for complicated ulcer disease has remained relativelyunchanged. In addition, the incidence and mortality of complicated PUD (i.e.,hemorrhage and perforation) have been steadily rising in the elderly population,which constitutes most of those requiring emergency surgery for PUD. This trendis especially prominent in elderly women (4851). The increased prevalence of nonsteroidal anti-inammatory drug (NSAIDs) use among older people is be-lieved to be a major incriminating factor. NSAIDs damage the gastric mucosathrough the inhibition of prostaglandin synthesis and cytoprotective factors. Theuse of NSAIDs increases the risk of bleeding, perforation, and death from pepticulcers (5255).


Perforation of a peptic ulcer classically manifests as severe acute epigastric painwith radiation to one or both shoulders. The patient bends forward in agony andappears in distress. A lull period may follow as the initial chemical peritonitisbecomes diluted from increased peritoneal secretions. The pain may shift to theright lower abdominal quadrant as the irritating uid drains down the right para-colic gutter, but a generalized peritonitis is most common. Examination will re-veal a thready pulse, labored respirations, diffuse abdominal tenderness, rigidity,and distention. Free air that appears on an acute abdominal radiographic seriesshould conrm the diagnosis (56). However, this dramatic presentation is oftensubdued in the elderly patient (57, 58). It is not infrequent for perforation orbleeding to occur without any prior history or symptoms of PUD. Typical ulcerpain is less likely to be present in elderly patients, and the analgesic propertiesof NSAIDs may mask the severity of pain. Peritoneal signs may be lacking, andmental confusion can be the initial presentation. Distinguishing ndings between


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158 Vo and Wilson

Table 3 Clinical Differences Between Perforated Peptic Ulcer andColonic Perforation a

Favors perforated Favors colonicFeature peptic ulcer perforation

Age (yr) 50 60Location of pain at onset Upper half Lower half Duration of pain (h) 12 24Severity Dramatic Less severeBowel habit Normal AbnormalPrevious indigestion Present Absent

a From Ref. 1.

peptic ulcer perforation and colonic perforation are displayed in Table 3. Acutemyocardial infarction should be excluded in elderly patients with substernal orhigh epigastric pain. Abdominal radiographs may not show subdiaphragmaticfree air in 25% of cases. Upper gastrointestinal endoscopy or barium series canaid in the diagnosis.


The morbidity and mortality of complicated PUD are high, especially in elderlypatients taking anti-inammatory drugs and with multiple medical problems.

Morbidity occurs in about 65% of patients and consists of pneumonia, cardiacdysrhythmia, wound infection, urinary tract infection, and sepsis. Overall mortal-ity for emergency peptic ulcer surgery consisting of perforations, hemorrhage,and penetration is about 30% (59). Sepsis and multiple organ failure are theleading causes of death. Boey et al. found that a treatment delay of more than24 hours, concurrent medical diseases, and preoperative shock all increased themortality in patients with perforated peptic ulcers. The presence of one, two, orthree of these factors was associated with a mortality of 10%, 46%, and 100%,respectively (60). Svanes et al. also found that a delay of more than 24 hoursincreased mortality, morbidity, and length of hospital stay (61). Elderly patientsshould undergo the simplest surgical treatment consisting of explorative laparot-omy or laparoscopy and suture closure of the perforation. The rate of recurrencewith this is low (59).

Elderly patients with peptic ulcer bleeding are more likely to rebleed, re-quire an operation, and die compared with their younger counterparts, especiallyif they require more than 5 units of blood transfusion (62, 63). (See also Chapter19.) The risk of rebleeding is higher, about 70%, for patients admitted in shock.


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Resuscitation needs to be performed adequately but cautiously because elderlypatients will not tolerate hypotension as well and are at risk for cardiac failurewith overhydration. Treatment requires communication between the surgery teamand gastrointestinal endoscopist for initial attempts at hemostasis. Endoscopicstigmata of a visible vessel or sentinel clot in the ulcer base indicates a high risk of rebleeding. The surgical procedure depends on the condition of the patient,age, location of the ulcer, and the treatment preference and training of the individ-ual surgeon. These can include simple closure with or without omental patch,vagotomy and drainage, pyloroplasty or gastrojejunostomy, or resection. Endo-scopically or radiographically documented peptic ulcer should be followed untilhealing occurs. Cancer or Zollinger-Ellison syndrome should be suspected if heal-ing has not occurred within 8 weeks.

VIII. COMPLICATED DIVERTICULAR DISEASE


Most colonic diverticula are acquired and considered false because they con-sist of only herniated mucosa and submucosa. A low-ber diet is believed to playa causative role. The prevalence of colonic diverticula in Western countries issignicantly higher and increases with age. Only about 10% to 20% of personswith documented colonic diverticulosis will have symptomatic disease develop(i.e., acute diverticulitis or hemorrhage) (64). Complicated diverticular diseaseoccurs primarily in the middle-aged and elderly populations, with about three-quarters of all patients hospitalized for acute diverticulitis being older than 60.

Acute diverticulitis is the most common complication and occurs when a di-vertculum becomes inamed and perforates. The sigmoid colon is invariably in-volved in more than 90% of all cases. Contained perforation may result in abscessformation, stulization, small bowel obstruction from adhesions, and large bowelobstruction from brotic luminal narrowing after repeated episodes. Free perfora-tion may lead to generalized peritonitis.


Acute diverticulitis resembles acute appendicitis in pathophysiology and presen-tation except the pain is situated in the left lower quadrant. The attack occurssuddenly, and the pain can be steady or colicky in nature. The location of thepain may be variable because of the redundancy of the sigmoid colon and occa-sionally can be felt in the suprapubic area, right lower quadrant, or throughoutthe lower abdomen. When located in the right lower quadrant, it can easily bemistaken for acute appendicitis. Passage of atus or stool may alleviate the pain.Alteration in bowel habits, nausea, and vomiting are not uncommon. Urinary


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160 Vo and Wilson

symptoms may occur when adjacent bladder irritation is present. Physical nd-ings consist of low-grade fever, mild abdominal distention, left lower quadranttenderness and or mass, and leukocytosis. Caution must be taken to not underesti-mate the extent of disease in the elderly because their symptoms may be insidiousand attenuated (65). Plain abdominal lms may show nonspecic ndings of ileus or obstruction, free air in the bladder indicating a colovesical stula, or apneumoperitoneum suggesting free perforation of a diverticulum. Abdominal CTscan with water-soluble contrast enema is the initial study of choice and affordsthe option of percutaneous drainage of any abscesses identied. Barium enemaand lower endoscopy should be avoided during the acute attack because of possi-ble leakage of barium into the peritoneal cavity and the risk of perforation fromhigh pressure.


Most patients with acute diverticulitis will have their disease resolve with medicaltreatment consisting of bowel rest, hydration, and antibiotics. Oral feeding isslowly advanced as the inammation subsides and a stool-bulking agent started.The patient should be evaluated with colonoscopy or barium enema several weeksafter resolution of the initial attack. The risk of another attack is 25%, usuallyoccurring within the rst 5 years, for those whose disease resolves with medicaltherapy (66).

Approximately 25% of patients hospitalized with acute diverticulitis willrequire surgical treatment. Surgery is indicated for cases refractory to medicaltreatment, recurrent diverticulitis that is associated with increased rate of compli-

cations, and age younger than 50. Patients experiencing their rst episode of acute diverticulitis before the age of 50 are at high risk for recurrent diverticulardisease requiring urgent operation and thus should undergo elective resectionafter resolution of their initial episode (67). Recurrent diverticulitis after resectionis infrequent, occurring in 3% to 7% of cases. In cases of free perforation withperitonitis, abscess formation, obstruction, or stula formation, surgery is manda-tory. The operative mortality rate is about 5% in recent reports.

The type of operation is determined mainly by the surgeons experienceand preference. Efforts should be made to convert an emergency operation intoan urgent or elective one. The use of intravenous antibiotics and CT-guided percu-taneous catheter drainage of well-localized paracolic abscesses have played alarge role in promoting successful one-stage operative procedures when perito-neal contamination is slight and contained and the patient is in good health (68).This consists of resection of diseased colon with anastomosis during the sameoperation. In the emergency setting, especially with elderly patients, a two-stageprocedure is preferable (69). This consists of primary resection with the proximalend of colon brought out as temporary colostomy and the distal end closed into


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a Hartmanns pouch or exteriorized as a mucous stula. Reanastomosis is per-formed at a second operation after the infection subsides. Three-stage proceduresare not performed commonly today but may retain a role in colonic obstructionresulting from diverticulitis.

IX. CONCLUSION

Improving the outcome of acute abdominal disease in the elderly patient requiresaction on three fronts. Patients must be educated to seek medical attention early inthe course of symptoms. The primary care physician should evaluate nonspecicabdominal complaints in the elderly and seek surgical referral for elective condi-tions before development of complications necessitates urgent operation. Last,the surgeon must recognize the variable presentations and higher morbidity andmortality associated with advanced age and therefore not delay treatment whileawaiting a denitive diagnosis.

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3. Crump C. The incidence of gallstones and gallbladder disease. Surg Gynecol Obstet1981; 53:447455.

4. Reiss R, Deutsch AA. Emergency abdominal procedures in patients over 70. J Ger-ontology 1985; 40:154158.

5. Morrow DJ, Thompson J, Wilson SE. Acute cholecystitis in the elderly. Arch Surg1978; 113:11491152.

6. Chock E, Wolfe BM, Matolo NM. Acute suppurative cholangitis. Surg Clin NorthAm 1981; 61:885892.

7. Harness JK, Strodel WE, Talsma SE. Symptomatic bilieary tract disease in the el-derly patient. Am Surgeon 1986; 52:442445.

8. Edlund G, Ljungdahl M. Acute cholecystitis in the elderly. Am J Surg 1990; 59(3):414416.

9. Magnuson TH, Ratner LE, Zenilman ME, Bender JS. Laparoscopic cholecystec-tomy: applicability in the geriatric population. Am Surgeon 1997; 63:9196.

10. Le CM, Fan ST, Liu CL, Lai EC, Wong J. Early decision for conversion of laparos-copic to open cholecystectomy for treatment of acute cholecystitis. Am J Surg 1997;173:513517.

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