1. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 1
1 ACUTE ABDOMINAL PAIN
David I. Soybel, M.D., F.A.C.S., Romano Delcore, M.D., F.A.C.S.
The term acute abdominal pain generally refers to previously undi- pointing.6 For this reason, the use of standardized history and phys-
agnosed pain that arises suddenly and is of less than 7 days’ (usual- ical forms, with or without the aid of diagnostic computer pro-
ly less than 48 hours’) duration.1 It may be caused by a great variety grams, has been recommended.7-10 A large-scale study that includ-
of intraperitoneal disorders, many of which call for surgical treat- ed 16,737 patients with acute abdominal pain demonstrated that
ment, as well as by a range of extraperitoneal disorders,2 which typ- integration of computer-aided diagnosis into management yielded a
ically do not call for surgical treatment [see Clinical Evaluation,Ten- 20% improvement in diagnostic accuracy.7 The study also docu-
tative Differential Diagnosis, below]. Abdominal pain that persists mented statistically significant reductions in inappropriate admis-
for 6 hours or longer is usually caused by disorders of surgical sig- sions, negative laparotomies, serious management errors (e.g., fail-
nificance.3 The primary goals in the management of patients with ure to operate on patients who require surgery), and length of
acute abdominal pain are (1) to establish a differential diagnosis hospital stay, as well as statistically significant increases in the num-
and a plan for confirming the diagnosis through appropriate imag- ber of patients who were immediately discharged home without ad-
ing studies, (2) to determine whether operative intervention is nec- verse effects and the promptness with which those requiring surgery
essary, and (3) to prepare the patient for operation in a manner that underwent operation. Although many factors may have contributed
minimizes perioperative morbidity and mortality. to the observed benefits of computer-aided decision-making, it is
In many cases, these goals are easily accomplished. On occasion, clear that the use of structured and standardized means of collect-
however, the evaluation of patients with acute abdominal pain can ing clinical and laboratory data was crucial. An example of such a
be one of the most difficult challenges in clinical surgery. It is essen- structured data sheet is the pain chart developed by the World Or-
tial to keep in mind that most (at least two thirds) of the patients ganization of Gastroenterology (OMGE) [see Figure 1]. Because
who present with acute abdominal pain have disorders for which this pain chart is not exhaustive and does not cover all potential sit-
surgical intervention is not required.2,4,5 In addition, most clinicians uations, individual surgeons may want to add to it; however, they
depend on recognition of specific patterns and sequences of symp- would be well advised not to omit any of the symptoms and signs
toms and signs to determine the need for further testing and to on the OMGE data sheet from their routine examination of pa-
make decisions regarding the timing of operation; however, at least tients with acute abdominal pain.11
one third of patients with acute abdominal pain exhibit atypical fea- The patient’s own words often provide important clues to the
tures that render pattern recognition unreliable.2,5 Finally, it is not correct diagnosis.The examiner should refrain from suggesting spe-
clear that individual clinicians always or even usually agree on pre- cific symptoms, except as a last resort. Any questions that must be
senting symptoms and physical signs. In one study of abdominal asked should be open-ended—for example, “What happens when
pain in children, agreement between individual observers was you eat?” rather than “Does eating make the pain worse?” Leading
reached 50% of the time for the physical sign of rebound tender- questions should be avoided. When a leading question must be
ness; however, for five other signs (abdominal distention, abdominal asked, it should be posed first as a negative question (i.e., one that
tenderness to percussion, abdominal tenderness to palpation, ab- calls for an answer in the negative) because a negative answer to a
dominal guarding, and bowel sounds), interobserver agreement was question is more likely to be honest and accurate. For example, if
not reached in more than one third of patients.These findings high- peritoneal inflammation is suspected, the question asked should be
light the difficulties inherent in evaluation and management of “Does coughing make the pain better?” rather than “Does cough-
acute abdominal pain. In addition, they emphasize the importance ing make the pain worse?”
of integrating care among different providers to minimize loss of in- The mode of onset of abdominal pain may help the examiner de-
formation and maximize continuity of care. termine the severity of the underlying disease. Pain that has a sud-
den onset suggests an intra-abdominal catastrophe, such as a rup-
tured abdominal aortic aneurysm (AAA), a perforated viscus, or a
Clinical Evaluation ruptured ectopic pregnancy; a near loss of consciousness or stamina
associated with sudden-onset pain should heighten the level of con-
HISTORY
cern for such a catastrophe. Rapidly progressive pain that becomes
A careful and methodical intensely focused in a well-defined area within a period of a few
clinical history should be minutes to an hour or two suggests a condition such as acute chole-
obtained. Key features of cystitis or pancreatitis. Pain that has a gradual onset over several
the history include the di- hours, usually beginning as slight or vague discomfort and slowly
mensions of pain (i.e., mode of onset, duration, frequency, charac- progressing to steady and more localized pain, suggests a subacute
ter, location, chronology, radiation, and intensity), as well as the process and is characteristic of processes that lead to peritoneal in-
presence or absence of any aggravating or alleviating factors and as- flammation. Numerous disorders may be associated with this mode
sociated symptoms. Often, such a history is more valuable than any of onset, including acute appendicitis, diverticulitis, pelvic inflam-
single laboratory or x-ray finding and determines the course of sub- matory disease (PID), and intestinal obstruction.
sequent evaluation and management. Pain can be either intermittent or continuous. Intermittent or
Unfortunately, when the ability of clinicians to take an organized cramping pain (colic) is pain that occurs for a short period (a few
and accurate history has been studied, the results have been disap- minutes), followed by longer periods (a few minutes to one-half

2. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 2
Patient presents with acute abdominal pain
Assessment of Obtain clinical history
Acute Abdominal Pain
Assess mode of onset, duration, frequency, character, location,
chronology, radiation, and intensity of pain.
Look for aggravating or alleviating factors and associated symptoms.
Use structured data sheets if possible.
Generate working diagnosis Perform basic investigative studies
Proceed with subsequent management on the basis Laboratory: complete blood count, hematocrit, electrolytes, creatinine,
of the working diagnosis. blood urea nitrogen, glucose, liver function tests, amylase, lipase,
Reevaluate patient repeatedly. If patient does not urinalysis, pregnancy test, ECG (if patient is elderly or has
respond to treatment as expected, reassess working atherosclerosis).
diagnosis and return to differential diagnosis. Imaging: Perform US or CT as indicated by results of examination and
basic laboratory studies.
Patient has acute surgical abdomen Patient has subacute surgical abdomen
Operate immediately. Treat surgically when diagnosis is confirmed.
Conditions necessitating immediate laparotomy
include ruptured abdominal aortic or visceral
aneurysm, ruptured ectopic pregnancy,
spontaneous hepatic or splenic rupture, major
blunt or penetrating abdominal trauma, and
hemoperitoneum from various causes. Patient requires urgent laparotomy Patient should be hospitalized
or laparoscopy and observed
Severe hemodynamic instability is the essential
indication. Conditions necessitating urgent Observe patient carefully, and
laparotomy include perforated reevaluate condition periodically.
hollow viscus, appendicitis, Meckel Consider additional investigative
diverticulitis, strangulated hernia, studies (e.g., CT, US, diagnostic
mesenteric ischemia, and ectopic peritoneal lavage, radionuclide
pregnancy (unruptured). imaging, angiography, MRI, and
Laparoscopy is recommended for GI endoscopy).
acute appendicitis and perforated Diagnostic laparoscopy is
ulcers (provided that surgeon has recommended if pain persists after
sufficient experience and a period of observation.
competence with the technique).
Patient requires early laparotomy Patient is candidate for elective Diagnosis is uncertain,
or laparoscopy laparotomy or laparoscopy or patient has suspected
nonsurgical abdomen
Early laparotomy or laparoscopy is Elective laparotomy or laparoscopy
reserved for patients whose conditions is reserved for patients who are Reevaluate patient as
are unlikely to become life threatening highly likely to respond to appropriate
if operation is delayed for 24–48 conservative medical management (see facing page).
hr (e.g., those with uncomplicated or whose conditions are highly
intestinal obstruction, uncomplicated unlikely to become life threatening
acute cholecystitis, uncomplicated during prolonged evaluation (e.g.,
acute diverticulitis, or nonstrangulated those with IBD, peptic ulcer disease,
incarcerated hernia). pancreatitis, or endometriosis).

3. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 3
Generate tentative differential diagnosis
Remember that the majority of patients will turn out to have nonsurgical
diagnoses.
Take into account effects of age and gender on diagnostic possibilities.
Perform physical examination
Evaluate general appearance and ability to answer questions; estimate
degree of obvious pain; note position in bed; identify area of maximal
pain; look for extra-abdominal causes of pain and signs of systemic illness.
Perform systematic abdominal examination: (1) inspection,
(2) auscultation, (3) percussion, (4) palpation.
Perform rectal, genital, and pelvic examinations.
Patient has abdominal pain of uncertain origin Patient has nonsurgical condition or chronic
relapsing condition that does not necessitate
Observe patient to determine whether operation operative intervention
is indicated.
Nonsurgical conditions causing acute
abdominal pain include both extraperitoneal
[see Table 2] and intraperitoneal disorders.
Patient should be hospitalized Patient can be evaluated in
and observed outpatient setting Patient should be hospitalized and observed
Provide narcotic analgesia as Provide narcotic analgesia as appropriate.
appropriate.
Observe patient carefully, and reevaluate
Observe patient carefully, and condition periodically.
reevaluate condition periodically.
Consider additional investigative Consider additional investigative studies.
studies. CT and US may be
especially useful.
Diagnosis is uncertain Diagnosis is
or patient has nonsurgical
suspected
surgical abdomen Refer patient for
medical management.
Reevaluate patient
Patient has suspected surgical Diagnosis is uncertain, or patient as appropriate
abdomen has suspected nonsurgical (see above, left, and
abdomen facing page).
Reevaluate patient as appropriate
(see facing page). Reevaluate patient as appropriate
(see above, right, and facing page).

4. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 4
ABDOMINAL PAIN CHART
NAME REG. NUMBER
MALE FEMALE AGE FORM FILLED BY
MODE OF ARRIVAL DATE TIME
Site of Pain Aggravating Factors Progression of Pain
movement better
At Onset
coughing same
PAIN
respiration worse
food
Duration
At Present other
none Type
intermittent
Relieving Factors
steady
lying still
colicky
vomiting
Radiation
antacids Severity
food moderate
other severe
none
Nausea Bowels Previous Similar Pain
yes no normal yes no
constipation
Vomiting Previous Abdominal Surgery
diarrhea
yes no yes no
blood
HISTORY
Anorexia mucus Drugs for Abdominal Pain
yes no yes no
Micturition
Indigestion normal Female-LMP
yes no frequency pregnant
dysuria vaginal discharge
Jaundice
dark dizzy/faint
yes no
hematuria
Temp. Pulse Location of Tenderness Initial Diagnosis & Plan
BP
Mood Rebound
normal yes no
upset Results
Guarding
anxious amylase
yes no
blood count (WBC)
Color
Rigidity urine
normal
yes no x-ray
pale
flushed Mass
yes no
EXAMINATION
jaundiced
cyanotic Murphy’s Sign Present
other
Intestinal Movement yes no
normal Bowel Sounds
poor/nil normal Diagnosis & Plan after Investigation
peristalsis absent
Scars increased
yes no Rectal-Vaginal Tenderness
Distention left
yes no right (time )
general
mass Discharge Diagnosis
none
History and examination of other systems on separate case notes.
Figure 1 Shown on facing page is a data sheet modified from the abdominal pain chart developed by the
OMGE.10

5. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 5
hour) of complete remission during which there is no pain at all. In- tensity of the pain and the patient’s reaction to it because there ap-
termittent pain is characteristic of obstruction of a hollow viscus pear to be significant individual differences with respect to tolerance
and results from vigorous peristalsis in the wall of the viscus proxi- of and reaction to pain. Pain that is intense enough to awaken the
mal to the site of obstruction.This pain is perceived as deep in the patient from sleep usually indicates a significant underlying organic
abdomen and is poorly localized.The patient is restless, may writhe cause. Past episodes of pain and factors that aggravate or relieve the
about incessantly in an effort to find a comfortable position, and of- pain often provide useful diagnostic clues. For example, pain caused
ten presses on the abdominal wall in an attempt to alleviate the by peritonitis tends to be exacerbated by motion, deep breathing,
pain. Whereas the intermittent pain associated with intestinal ob- coughing, or sneezing, and patients with peritonitis tend to lie qui-
struction (typically described as gripping and mounting) is usually etly in bed and avoid any movement.The typical pain of acute pan-
severe but bearable, the pain associated with obstruction of small creatitis is exacerbated by lying down and relieved by sitting up.
conduits (e.g., the biliary tract, the ureters, and the uterine tubes) Pain that is relieved by eating or taking antacids suggests duodenal
often becomes unbearable. Obstruction of the gallbladder or the ulcer disease, whereas diffuse abdominal pain that appears 30 min-
bile ducts gives rise to a type of pain often referred to as biliary col- utes to 1 hour after meals suggests intestinal angina.
ic; however, this term is a misnomer, in that biliary pain is usually Associated gastrointestinal symptoms (e.g., nausea, vomiting,
constant because of the lack of a strong muscular coat in the biliary anorexia, diarrhea, and constipation) often accompany abdominal
tree and the absence of regular peristalsis. pain; however, these symptoms are nonspecific and therefore may
Continuous or constant pain is pain that is present for hours or not be of great value in the differential diagnosis.Vomiting in partic-
days without any period of complete relief; it is more common than ular is common: when sufficiently stimulated by pain impulses trav-
intermittent pain. Continuous pain is usually indicative of a process eling via secondary visceral afferent fibers, the medullary vomiting
that will lead, or has already led, to peritoneal inflammation or is- centers activate efferent fibers and cause reflex vomiting. Once again,
chemia. It may be of steady intensity throughout, or it may be asso- the chronology of events is important, in that pain often precedes
ciated with intermittent pain. For example, the typical colicky pain vomiting in patients with conditions necessitating operation, where-
associated with simple intestinal obstruction changes when strangu- as the opposite is usually the case in patients with medical (i.e., non-
lation occurs, becoming continuous pain that persists between surgical) conditions.5,12 This is particularly true for adult patients
episodes or waves of cramping pain. with acute appendicitis, in whom pain almost always precedes vom-
Certain types of pain are generally held to be typical of certain iting by several hours. In children, vomiting is commonly observed
pathologic states. For example, the pain of a perforated ulcer is often closer to the onset of the pain, though it is rarely the initial symptom.
described as burning, that of a dissecting aneurysm as tearing, and Similarly, constipation may result from a reflex paralytic ileus
that of bowel obstruction as gripping. One may imagine that the first when sufficiently stimulated visceral afferent fibers activate effer-
type of pain is explained by the efflux of acid, the second by the sud- ent sympathetic fibers (splanchnic nerves) to reduce intestinal
den expansion of the retroperitoneum, and the third by the churning peristalsis. Diarrhea is characteristic of gastroenteritis but may
of hyperperistalsis. Colorful as these images may be, in most cases, also accompany incomplete intestinal or colonic obstruction.
the pain begins in a nondescript way. It is only by carefully following More significant is a history of obstipation, because if it can be
the patient’s description of the evolution and time course of the pain definitely established that a patient with acute abdominal pain has
that such images may be formed with confidence. not passed gas or stool for 24 to 48 hours, it is certain that some
For several reasons—atypical pain patterns, dual innervation by degree of intestinal obstruction is present. Other associated symp-
visceral and somatic afferents, normal variations in organ position, toms that should be noted include jaundice, melena, hema-
and widely diverse underlying pathologic states—the location of ab- tochezia, hematemesis, and hematuria.These symptoms are much
dominal pain is only a rough guide to diagnosis. It is nevertheless more specific than the ones just discussed and can be extremely
true that in most disorders, the pain tends to occur in characteristic valuable in the differential diagnosis. Most conditions that cause
locations, such as the right upper quadrant (cholecystitis), the right acute abdominal pain of surgical significance are associated with
lower quadrant (appendicitis), the epigastrium (pancreatitis), or the some degree of fever if they are allowed to continue long enough.
left lower quadrant (sigmoid diverticulitis) [see Figure 2]. It is impor- Fever suggests an inflammatory process; however, it is usually low
tant to determine the location of the pain at onset because this may grade and often absent altogether, particularly in elderly and im-
differ from the location at the time of presentation (so-called shifting munocompromised patients.The combination of a high fever with
pain). In fact, the chronological sequence of events in the patient’s chills and rigors indicates bacteremia, and concomitant changes
history is often more important for diagnosis than the location of the in mental status (e.g., agitation, disorientation, and lethargy) sug-
pain alone. For example, the classic pain of appendicitis begins in the gest impending septic shock.
periumbilical region and settles in the right lower quadrant. A similar A history of trauma (even if the patient considers the traumatic
shift in location can occur when escaping gastroduodenal contents event trivial) should be actively sought in all cases of unexplained
from a perforated ulcer pool in the right lower quadrant. acute abdominal pain; such a history may not be readily volun-
It is also important to take into account radiation or referral of teered (as is often the case with trauma resulting from domestic vio-
the pain, which tends to occur in characteristic patterns [see Figure lence).The history may be particularly relevant in a patient taking
3]. For example, biliary pain is referred to the right subscapular anticoagulants and presenting with acute onset of abdominal pain
area, and the boring pain of pancreatitis typically radiates straight accompanied by tenderness but no clear signs of inflammation.
through to the back. Obstruction of the small intestine and the Hematoma within the rectus muscle sheath can easily be mistaken
proximal colon is referred to the umbilicus, and obstruction distal for appendicitis or other lower abdominal illnesses; hematoma else-
to the splenic flexure is often referred to the suprapubic area. Spasm where can produce symptoms of obstruction or acute bleeding into
in the ureter often radiates to the suprapubic area and into the the peritoneum and the retroperitoneum. In female patients, it is es-
groin.The more severe the pain is, the more likely it is to be associ- sential to obtain a detailed gynecologic history that includes the
ated with referral to other areas. timing of symptoms within the menstrual cycle, the date of the last
The intensity or severity of the pain is related to the magnitude of menses, previous and current use of contraception, any abnormal
the underlying insult. It is important to distinguish between the in- vaginal bleeding or discharge, an obstetric history, and any risk fac-

6. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 6
a b
EPIGASTRIC REGION
Peptic Ulcer
Gastritis
Pancreatitis
Duodenitis
Gastroenteritis
Early Appendicitis
Mesenteric Adenitis
UMBILICAL REGION
Mesenteric Thrombosis
Early Appendicitis
Intestinal Obstruction
Gastroenteritis
Inflammatory Bowel
Pancreatitis
Disease
Hernia
Mesenteric Adenitis
Mesenteric Thrombosis
Intestinal Obstruction
DIFFUSE
Inflammatory Bowel Disease
Peritonitis
Aneurysm
Early Appendicitis
Pancreatitis
HYPOGASTRIC REGION
Leukemia
Cystitis
Sickle Cell Crisis
Diverticulitis
Gastroenteritis
Appendicitis
Mesenteric Adenitis
Prostatism
Mesenteric Thrombosis
Salpingitis
Intestinal Obstruction
Hernia
Inflammatory Bowel
Ovarian Cyst/Torsion
Disease
Endometriosis
Aneurysm
Ectopic Pregnancy
Metabolic Causes
Nephrolithiasis
Toxic Causes
Intestinal Obstruction
Inflammatory Bowel Disease
Abdominal Wall Hematoma
c
RIGHT UPPER QUADRANT LEFT UPPER QUADRANT
Cholecystitis Gastritis
Choledocholithiasis Pancreatitis
Hepatitis Splenic Enlargement
Hepatic Abscess Splenic Rupture
Hepatomegaly from Splenic Infarction
Congestive Heart Failure Splenic Aneurysm
Peptic Ulcer Pyelonephritis
Pancreatitis Nephrolithiasis
Retrocecal Appendicitis Herpes Zoster
Pyelonephritis Myocardial Ischemia
Nephrolithiasis Pneumonia
Herpes Zoster Empyema
Myocardial Ischemia Diverticulitis
Pericarditis Intestinal Obstruction
Pneumonia Inflammatory Bowel Disease
Empyema
Gastritis LEFT LOWER QUADRANT
Duodenitis Diverticulitis
Intestinal Obstruction Intestinal Obstruction
Inflammatory Bowel Disease Inflammatory Bowel Disease
Appendicitis
RIGHT LOWER QUADRANT Leaking Aneurysm
Appendicitis Abdominal Wall Hematoma
Intestinal Obstruction Ectopic Pregnancy
Inflammatory Bowel Disease Mittelschmerz
Mesenteric Adenitis Ovarian Cyst/Torsion
Diverticulitis Salpingitis
Cholecystitis Endometriosis
Perforated Ulcer Ureteral Calculi
Leaking Aneurysm Pyelonephritis
Abdominal Wall Hematoma Nephrolithiasis
Ectopic Pregnancy Seminal Vesiculitis
Ovarian Cyst/Torsion Psoas Abscess
Salpingitis Hernia
Mittelschmerz
Endometriosis
Ureteral Calculi Figure 2 In most disorders that give rise to acute abdominal pain, the pain tends to occur
Pyelonephritis in specific locations. (a) Diffuse pain suggests a certain set of diagnostic possibilities. (b)
Nephrolithiasis Differing groups of disorders give rise to abdominal pain in the epigastric, umbilical, and
Seminal Vesiculitis
hypogastric regions. (c) Disorders that give rise to acute abdominal pain may be grouped
Psoas Abscess
Hernia according to the quadrant of the abdomen in which pain tends to occur.

7. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 7
Esophagus Perforated Duodenal Ulcer
(Diaphragmatic Irritation)
Stomach
Liver and Biliary Colic
Gallbladder
Pylorus
Colon Acute Pancreatitis and
Renal Colic
Left and Right
Kidneys
Uterine and Rectal Pain
Ureter
Figure 3 Pain of abdominal origin tends to be referred in characteristic patterns.80 The more severe the pain is, the
more likely it is to be referred. Shown are anterior (left) and posterior (right) areas of referred pain.
tors for ectopic pregnancy (e.g., PID, use of an intrauterine device, North American emergency rooms, it is important to consider
or previous ectopic or tubal surgery). endemic diseases, including tuberculosis,14,15 parasitic diseases,16-
A complete history of previous medical conditions must be ob- 18 bezoars from unusual dietary habits,19,20 and unusual malig-
tained because associated diseases of the cardiac, pulmonary, and nancies.21,22
renal systems may give rise to acute abdominal symptoms and may The value of detailed epidemiologic knowledge notwithstanding,
also significantly affect the morbidity and mortality associated with it is worthwhile to keep in mind the truism that common things are
surgical intervention. Weight changes, past illnesses, recent travel, common. Regarding which things are common, the most extensive
environmental exposure to toxins or infectious agents, and medica- information currently available comes from the ongoing survey be-
tions used should also be investigated. A history of previous abdom- gun in 1977 by the Research Committee of the OMGE. As of the
inal operations should be obtained but should not be relied on too last progress report on this survey, which was published in 1988,23
heavily in the absence of operative reports. A careful family history more than 200 physicians at 26 centers in 17 countries had accu-
is important for detection of hereditary disorders that may cause mulated data on 10,320 patients with acute abdominal pain [see
acute abdominal pain. A detailed social history should also be ob- Table 3].The most common diagnosis in these patients was nonspe-
tained that includes any history of tobacco, alcohol, or illicit drug cific abdominal pain (NSAP)—that is, the retrospective diagnosis of
use, as well as a sexual history. exclusion in which no cause for the pain can be identified.24,25 Non-
specific abdominal pain accounted for 34% of all patients seen; the
TENTATIVE DIFFERENTIAL
four most common diagnoses accounted for more than 75%.The
DIAGNOSIS
most common surgical diagnosis in the OMGE survey was acute
Once the history has appendicitis, followed by acute cholecystitis, small bowel obstruc-
been obtained, the examin- tion, and gynecologic disorders. Relatively few patients had perfo-
er should generate a tenta- rated peptic ulcer, a finding that confirms the current downward
tive differential diagnosis trend in the incidence of this condition. Cancer was found to be a
and carry out the physical significant cause of acute abdominal pain.There was little variation
examination in search of in the geographic distribution of surgical causes of acute abdominal
specific signs or findings that either rule out or confirm the diag- pain (i.e., conditions necessitating operation) among developed
nostic possibilities. Given the diversity of conditions that can countries. In patients who required operation, the most common
cause acute abdominal pain [see Tables 1 and 2], there is no substi- causes were acute appendicitis (42.6%), acute cholecystitis (14.7%),
tute for general awareness of the most common causes of acute small bowel obstruction (6.2%), perforated peptic ulcer (3.7%),
abdominal pain and the influence of age, gender, and geography and acute pancreatitis (4.5%).23 The OMGE survey’s finding that
on the likelihood of any of these potential causes. Although acute NSAP was the most common diagnosis in patients with acute ab-
abdominal pain is the most common surgical emergency and dominal pain has been confirmed by several srudies12,13,25; the find-
most non–trauma-related surgical admissions (and 1% of all hos- ing that acute appendicitis, cholecystitis, and intestinal obstruction
pital admissions) are accounted for by patients complaining of were the three most common diagnoses in patients with acute ab-
abdominal pain, little information is available regarding the clini- dominal pain who require operation has also been amply confirmed
cal spectrum of disease in these patients.13 Nevertheless, detailed [see Table 3].1,12,13
epidemiologic information can be an invaluable asset in the diag- The data described so far provide a comprehensive picture of
nosis and treatment of acute abdominal pain. Now that patients the most likely diagnoses for patients with acute abdominal pain in
from different parts of the world are increasingly being seen in many centers around the world; however, this picture does not take

8. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 8
Table 1 Intraperitoneal Causes of Acute Abdominal Pain81
Inflammatory Pancreatic abscess Torsion or degeneration of fibroid
Peritoneal Hepatic abscess Ectopic pregnancy
Chemical and nonbacterial peritonitis Splenic abscess
Hemoperitoneum
Perforated peptic ulcer/biliary tree, Mesenteric
Ruptured hepatic neoplasm
pancreatitis, ruptured ovarian cyst, Lymphadenitis (bacterial, viral)
mittelschmerz Spontaneous splenic rupture
Epiploic appendagitis
Bacterial peritonitis Ruptured mesentery
Pelvic
Primary peritonitis Ruptured uterus
Pelvic inflammatory disease (salpingitis)
Pneumococcal, streptococcal, Ruptured graafian follicle
tuberculous Tubo-ovarian abscess
Ruptured ectopic pregnancy
Spontaneous bacterial peritonitis Endometritis
Ruptured aortic or visceral aneurysm
Perforated hollow viscus Mechanical (obstruction, acute distention) Ischemic
Esophagus, stomach, duodenum, small Hollow visceral
intestine, bile duct, gallbladder, colon, Mesenteric thrombosis
urinary bladder Intestinal obstruction Hepatic infarction (toxemia, purpura)
Hollow visceral Adhesions, hernias, neoplasms, volvulus Splenic infarction
Appendicitis Intussusception, gallstone ileus, foreign Omental ischemia
bodies
Cholecystitis Strangulated hernia
Bezoars, parasites
Peptic ulcer
Biliary obstruction Neoplastic
Gastroenteritis
Calculi, neoplasms, choledochal cyst, Primary or metastatic intraperitoneal
Gastritis hemobilia neoplasms
Duodenitis Solid visceral Traumatic
Inflammatory bowel disease Acute splenomegaly Blunt trauma
Meckel diverticulitis Acute hepatomegaly (congestive heart Penetrating trauma
Colitis (bacterial, amebic) failure, Budd-Chiari syndrome)
Iatrogenic trauma
Diverticulitis Mesenteric
Domestic violence
Solid visceral Omental torsion
Pancreatitis Pelvic Miscellaneous
Hepatitis Ovarian cyst Endometriosis
PHYSICAL EXAMINATION
into account the effect of age on the relative likelihood of the vari-
ous potential diagnoses. It is well known that the disease spectrum In the physical examina-
of acute abdominal pain is different in different age groups, espe- tion of a patient, as in the
cially in the very old4,26,27 and the very young.28-30 In the OMGE taking of the history, there is
survey, well over 90% of cases of acute abdominal pain in children no substitute for organiza-
were diagnosed as acute appendicitis (32%) or NSAP (62%).28 tion and patience; the
Similar age-related differences in the spectrum of disease have amount of information that
been confirmed by other studies,16 as have various gender-related can be obtained is directly
differences. proportional to the gentleness and thoroughness of the examiner.
This variation in the disease spectrum is readily apparent when The physical examination begins with a brief but thorough evalua-
the 10,320 patients from the OMGE survey are segregated by age tion of the patient’s general appearance and ability to answer ques-
[see Table 4]. In patients 50 years of age or older,27 cholecystitis was tions.The degree of obvious pain should be estimated.The patient’s
more common than either NSAP or acute appendicitis; small position in bed should be noted. A patient who lies motionless with
bowel obstruction, diverticular disease, and pancreatitis were all flexed hips and knees is more likely to have generalized peritonitis. A
approximately five times more common than in patients younger restless patient who writhes about in bed is more likely to have col-
than 50 years. Hernias were also a much more common problem icky pain.
in older patients. In the entire group of patients, only one of every The area of maximal pain should be identified before the physi-
10 instances of intestinal obstruction was attributable to a hernia, cal examination is begun.The examiner can easily do this by simply
whereas in patients 50 years of age or older, one of every three in- asking the patient to cough and then to point with two fingers to the
stances was caused by an undiagnosed hernia. Cancer was 40 area where pain seems to be focused. This allows the examiner to
times more likely to be the cause of acute abdominal pain in pa- avoid the area in the early stages of the examination and to confirm
tients 50 years of age or older; vascular diseases (including my- it at a later stage without causing the patient unnecessary discom-
ocardial infarction, mesenteric ischemia, and ruptured AAA) were fort in the meantime.
25 times more common in patients 50 years of age or older and The physical examination should be directed, in the sense that it
100 times more common in patients older than 70 years.What is should address critical findings that would confirm or exclude the
more, outcome was clearly related to age: mortality was signifi- likeliest disorders in the differential diagnosis. In this context, how-
cantly higher in patients older than 70 years (5%) than in those ever, it should be complete. Some processes that can cause abdom-
younger than 50 years (< 1%). Whereas the peak incidence of inal pain occur within the chest (e.g., pneumonia, ischemic heart
acute abdominal pain occurred in patients in their teens and disease or arrhythmia, esophageal muscular disorders); thus, aus-
20s,28 the great majority of deaths occurred in patients older than cultation of the lungs and the heart is integral to the examination.
70 years.27 Pelvic examination should be performed in women, and examina-

9. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 9
tion of the rectum and the groin should be performed in all patients. proach is crucial: an examiner who methodically follows a set pat-
It should not be assumed that advanced imaging technology (e.g., tern of abdominal examination every time will be rewarded more
CT, MRI, or ultrasonography [US]) will provide the diagnosis most frequently than one who improvises haphazardly with each patient.
quickly or with the highest level of confidence.The sensitivity and The first step in the abdominal examination is careful inspection
specificity (not to mention the cost-effectiveness) of any laboratory of the anterior and posterior abdominal walls, the flanks, the per-
or imaging study are grounded in the intelligent gathering and cate- ineum, and the genitalia for previous surgical scars (possible adhe-
gorization of signs and symptoms.31,32 sions), hernias (incarceration or strangulation), distention (intestinal
Before attention is directed to the patient’s abdomen, signs of obstruction), obvious masses (distended gallbladder, abscesses, or
systemic illness should be sought. Systemic signs of shock (e.g., di- tumors), ecchymosis or abrasions (trauma), striae (pregnancy or as-
aphoresis, pallor, hypothermia, tachypnea, tachycardia with or- cites), an everted umbilicus (increased intra-abdominal pressure),
thostasis, and frank hypotension) usually accompany a rapidly pro- visible pulsations (aneurysm), visible peristalsis (obstruction), limi-
gressive or advanced intra-abdominal condition and, in the absence tation of movement of the abdominal wall with ventilatory move-
of extra-abdominal causes, are indications for immediate laparoto- ments (peritonitis), or engorged veins (portal hypertension).
my.The absence of any alteration in vital signs, however, does not The next recommended step in the abdominal examination is
necessarily exclude a serious intra-abdominal process. auscultation. Although it is important to note the presence (or ab-
Examination of the abdomen begins with the patient resting in a sence) of bowel sounds and their quality, auscultation is probably
comfortable supine position. A right-handed examiner should stand the least rewarding aspect of the physical examination. Severe intra-
on the patient’s right side, and the patient’s abdomen should be lev- abdominal conditions, even intra-abdominal catastrophes, may oc-
el with the elbow at rest. In some cases, to make sure that the exam- cur in patients with normal bowel sounds, and patients with silent
ination is unhurried and the patient’s anxiety is allayed, the examin- abdomens may have no significant intra-abdominal pathology at all.
er may find it useful to sit at the bedside.The examination should In general, however, the absence of bowel sounds indicates a para-
include inspection, auscultation, percussion, and palpation of all ar- lytic ileus; hyperactive or hypoactive bowel sounds often are varia-
eas of the abdomen, the flanks, and the groin (including all hernia tions of normal activity; and high-pitched bowel sounds with
orifices) in addition to rectal and genital examinations (and, in fe- splashes, tinkles (echoing as in a large cavern), or rushes (pro-
male patients, a full gynecologic examination). A systematic ap- longed, loud gurgles) indicate mechanical bowel obstruction.
Table 2 Extraperitoneal Causes of Acute Abdominal Pain
Genitourinary Endocrine Hematologic
Pyelonephritis Diabetic ketoacidosis Sickle cell crisis
Perinephric abscess Hyperparathyroidism (hypercalcemia) Acute leukemia
Renal infarct Acute adrenal insufficiency (Addisonian Acute hemolytic states
Nephrolithiasis crisis) Coagulopathies
Ureteral obstruction (lithiasis, tumor) Hyperthyroidism or hypothyroidism Pernicious anemia
Acute cystitis Musculoskeletal Other dyscrasias
Prostatitis Rectus sheath hematoma Vascular
Seminal vesiculitis Arthritis /diskitis of thoracolumbar spine Vasculitis
Epididymitis
Neurogenic Periarteritis
Orchitis
Testicular torsion Herpes zoster Toxins
Dysmenorrhea Tabes dorsalis Bacterial toxins (tetanus, staphylococcus)
Threatened abortion Nerve root compression Insect venom (black widow spider)
Spinal cord tumors Animal venom
Pulmonary Osteomyelitis of the spine Heavy metals (lead, arsenic, mercury)
Pneumonia
Abdominal epilepsy Poisonous mushrooms
Empyema
Abdominal migraine Drugs
Pulmonary embolus
Multiple sclerosis Withdrawal from narcotics
Pulmonary infarction
Pneumothorax Inflammatory Retroperitoneal
Schönlein-Henoch purpura Retroperitoneal hemorrhage (spontaneous
Cardiac adrenal hemorrhage)
Systemic lupus erythematosus
Myocardial ischemia Psoas abscess
Polyarteritis nodosa
Myocardial infarction
Dermatomyositis Psychogenic
Acute rheumatic fever
Scleroderma Hypochondriasis
Acute pericarditis
Infectious Somatization disorders
Metabolic
Bacterial Factitious
Acute intermittent porphyria
Parasitic (malaria) Munchausen syndrome
Familial Mediterranean fever
Viral (measles, mumps, infectious Malingering
Hypolipoproteinemia mononucleosis)
Hemochromatosis Rickettsial (Rocky Mountain spotted
Hereditary angioneurotic edema fever)

10. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 10
Table 3 Frequency of Specific Diagnoses in Patients with Acute Abdominal Pain
Frequency in Individual Studies (% of Patients)
Diagnosis
OMGE23 Wilson82 Irvin13 Brewer 12 de Dombal 1 Hawthorn 83
(N = 10,320) (N = 1,196) (N = 1,190) (N = 1,000) (N = 552) (N = 496)
Nonspecific abdominal pain 34.0 45.6 34.9 41.3 50.5 36.0
Acute appendicitis 28.1 15.6 16.8 4.3 26.3 14.9
Acute cholecystitis 9.7 5.8 5.1 2.5 7.6 5.9
Small bowel obstruction 4.1 2.6 14.8 2.5 3.6 8.6
Acute gynecologic disease 4.0 4.0 1.1 8.5 — —
Acute pancreatitis 2.9 1.3 2.4 — 2.9 2.1
Urologic disorders 2.9 4.7 5.9 11.4 — 12.8
Perforated peptic ulcer 2.5 2.3 2.5 2.0 3.1 —
Cancer 1.5 — 3.0 — — —
Diverticular disease 1.5 1.1 3.9 — 2.0 3.0
Dyspepsia 1.4 7.6 1.4 1.4 — —
Gastroenteritis — — 0.3 6.9 — 5.1
Inflammatory bowel disease — — 0.8 — — 2.1
Mesenteric adenitis — 3.6 — — — 1.5
Gastritis — 2.1 — 1.4 — —
Constipation — 2.4 — 2.3 — —
Amebic hepatic abscess 1.2 — 1.9 — — —
Miscellaneous 6.3 1.3 5.2 15.5 4.0 8.0
The third step is percussion to search for any areas of dullness, flu- (i.e., taut and rigid) throughout the respiratory cycle (so-called
id collections, sections of gas-filled bowel, or pockets of free air under boardlike abdomen).True involuntary guarding is indicative of lo-
the abdominal wall.Tympany may be present in patients with bowel calized or generalized peritonitis. It must be remembered that mus-
obstruction or hollow viscus perforation. Percussion can be useful as
a way of estimating organ size and of determining the presence of as-
cites (signaled by a fluid wave or shifting dullness). Gentle percussion Table 4 Frequency of Specific Diagnoses in
over the four quadrants of the abdomen can also be used to elicit a Younger and Older Patients with Acute Abdominal
sign of peritoneal irritation, and patients tolerate this maneuver rea- Pain in the OMGE Study23,27
sonably well. Pain associated with mild levels of percussion is a good
indicator of peritonitis if the maneuver is performed in the same way Frequency (% of Patients)
each time. In general, however, maneuvers associated with palpation Diagnosis
are best for determining whether peritonitis is present. Age < 50 Yr Age ≥ 50 Yr
The last step, palpation, is the most informative aspect of the (N = 6,317) (N = 2,406)
physical examination. Palpation of the abdomen must be done very
Nonspecific abdominal pain 39.5 15.7
gently to avoid causing additional pain early in the examination. It
should begin as far as possible from the area of maximal pain and Appendicitis 32.0 15.2
then should gradually advance toward this area, which should be the
Cholecystitis 6.3 20.9
last to be palpated. The examiner should place the entire hand on
the patient’s abdomen with the fingers together and extended, ap- Obstruction 2.5 12.3
plying pressure with the pulps (not the tips) of the fingers by flexing
Pancreatitis 1.6 7.3
the wrists and the metacarpophalangeal joints. It is essential to de-
termine whether true involuntary muscle guarding (muscle spasm) Diverticular disease < 0.1 5.5
is present.This determination is made by means of gentle palpation
Cancer < 0.1 4.1
over the abdominal wall while the patient takes a long, deep breath.
If guarding is voluntary, the underlying muscle immediately relaxes Hernia < 0.1 3.1
under the gentle pressure of the palpating hand. If, however, the pa-
Vascular disease < 0.1 2.3
tient has true involuntary guarding, the muscle remains in spasm

11. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 11
Table 5 Common Abdominal Signs and Findings Noted on Physical Examination6
Sign or Finding Description Associated Clinical Condition(s)
Aaron sign Referred pain or feeling of distress in epigastrium or precordial re- Acute appendicitis
gion on continued firm pressure over the McBurney point
Ballance sign Presence of dull percussion note in both flanks, constant on left side Ruptured spleen
but shifting with change of position on right side
Bassler sign Sharp pain elicited by pinching appendix between thumb of examin- Chronic appendicitis
er and iliacus muscle
Beevor sign Upward movement of umbilicus Paralysis of lower portions of rectus abdominis muscles
Blumberg sign Transient abdominal wall rebound tenderness Peritoneal inflammation
Carnett sign Disappearance of abdominal tenderness when anterior abdominal Abdominal pain of intra-abdominal origin
muscles are contracted
Chandelier sign Intense lower abdominal and pelvic pain on manipulation of cervix Pelvic inflammatory disease
Charcot sign Intermittent right upper quadrant abdominal pain, jaundice, and Choledocholithiasis
fever
Chaussier sign Severe epigastric pain in gravid female Prodrome of eclampsia
Claybrook sign Transmission of breath and heart sounds through abdominal wall Ruptured abdominal viscus
Courvoisier sign Palpable, nontender gallbladder in presence of clinical jaundice Periampullary neoplasm
Cruveilhier sign Varicose veins radiating from umbilicus (caput medusae) Portal hypertension
Cullen sign Periumbilical darkening of skin from blood Hemoperitoneum (especially in ruptured ectopic pregnancy)
Cutaneous Increased abdominal wall sensation to light touch Parietal peritoneal inflammation secondary to inflammatory
hyperesthesia intra-abdominal pathology
Dance sign Slight retraction in area of right iliac fossa Intussusception
Danforth sign Shoulder pain on inspiration Hemoperitoneum (especially in ruptured ectopic pregnancy)
Direct abdominal wall — Localized inflammation of abdominal wall, peritoneum, or an
tenderness intra-abdominal viscus
Fothergill sign Abdominal wall mass that does not cross midline and remains palpa- Rectus muscle hematoma
ble when rectus muscle is tense
(continued)
cle rigidity is relative: for example, muscle guarding may be less pro- the patient in the left lateral decubitus position and extending the
nounced or absent in debilitated and elderly patients who have poor right leg. In settings where appendicitis is suspected, pain on exten-
abdominal musculature. In addition, the evaluation of muscle sion of the right leg indicates that the psoas is irritated and thus that
guarding is dependent on the patient’s cooperation. the inflamed appendix is in a retrocecal position.The obturator sign
Palpation is also useful for determining the extent and severity of is elicited by raising the flexed right leg and rotating the thigh inter-
the patient’s tenderness. Diffuse tenderness indicates generalized nally. In settings where appendicitis is suspected, pain on rotation of
peritoneal inflammation. Mild diffuse tenderness without guarding the right thigh indicates that the obturator is irritated and thus that
usually indicates gastroenteritis or some other inflammatory intesti- the inflamed appendix is in a pelvic position. The Kehr sign is
nal process without peritoneal inflammation. Localized tenderness elicited when the patient is placed in the Trendelenburg position.
suggests an early stage of disease with limited peritoneal inflamma- Pain in the shoulder indicates irritation of the diaphragm by a nox-
tion. Rebound tenderness is elicited by applying gentle but deep ious fluid (e.g., gastric contents from a perforated ulcer, pus from a
pressure to the region of interest and then letting go abruptly. As a ruptured appendix, or free blood from a fallopian tube pregnancy).
means of distraction, the examiner may use the stethoscope to ap- Another useful maneuver is the Carnett test, in which the patient
ply the pressure.The main difficulties associated with palpation are elevates his or her head off the bed, thus tensing the abdominal
that the deep pressure may increase anxiety and that the surprise of muscles. When the pain is caused by abdominal wall conditions
the sudden withdrawal may elicit pain where peritoneal irritation is (e.g., rectal sheath hematoma), tenderness to palpation persists, but
not the cause. when the pain is caused by intraperitoneal conditions, tenderness to
Careful palpation can elicit several specific signs [see Table 5], palpation decreases or disappears (the Carnett sign).
such as the Rovsing sign (pain in the right lower quadrant when the Rectal, genital, and (in women) pelvic examinations are essential
left lower quadrant is palpated deeply), which is associated with to the evaluation of all patients with acute abdominal pain.The rec-
acute appendicitis, and the Murphy sign (arrest of inspiration when tal examination should include evaluation of sphincter tone, tender-
the right upper quadrant is deeply palpated), which is associated ness (localized versus diffuse), and prostate size and tenderness, as
with acute cholecystitis.These signs are indicative of localized peri- well as a search for the presence of hemorrhoids, masses, fecal im-
toneal inflammation. Similarly, specific maneuvers can elicit signs paction, foreign bodies, and gross or occult blood.The genital ex-
of localized peritoneal irritation.The psoas sign is elicited by placing amination should search for adenopathy, masses, discoloration,

12. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 12
Table 5—(continued)
Sign or Finding Description Associated Clinical Condition(s)
Grey Turner sign Local areas of discoloration around umbilicus and flanks Acute hemorrhagic pancreatitis
Iliopsoas sign Elevation and extension of leg against pressure of examiner’s hand Appendicitis (retrocecal) or an inflammatory mass in contact
causes pain with psoas
Left shoulder pain when patient is supine or in the Trendelenburg po-
Kehr sign sition (pain may occur spontaneously or after application of pres- Hemoperitoneum (especially ruptured spleen)
sure to left subcostal region)
Kustner sign Palpable mass anterior to uterus Dermoid cyst of ovary
Mannkopf sign Acceleration of pulse when a painful point is pressed on by examiner Absent in factitious abdominal pain
McClintock sign Heart rate > 100 beats/min 1 hr post partum Postpartum hemorrhage
Murphy sign Palpation of right upper abdominal quadrant during deep inspiration Acute cholecystitis
results in right upper quadrant abdominal pain
Obturator sign Flexion of right thigh at right angles to trunk and external rotation of Appendicitis (pelvic appendix); pelvic abscess; an inflammato-
same leg in supine position result in hypogastric pain ry mass in contact with muscle
Alteration in intensity of transmitted sound in intra-abdominal cavity
Puddle sign secondary to percussion when patient is positioned on all fours and Free peritoneal fluid
stethoscope is gradually moved toward flank opposite percussion
Ransohoff sign Yellow pigmentation in umbilical region Ruptured common bile duct
Rovsing sign Pain referred to the McBurney point on application of pressure to de- Acute appendicitis
scending colon
Subcutaneous
crepitance Palpable crepitus in abdominal wall Subcutaneous emphysema or gas gangrene
Increased abdominal muscle tone on exceedingly gentle palpation Early appendicitis; nephrolithiasis; ureterolithiasis; ovarian
Summer sign of right or left iliac fossa torsion
Ten Horn sign Pain caused by gentle traction on right spermatic cord Acute appendicitis
Right-sided tympany and left-sided dullness in supine position as a
Toma sign result of peritoneal inflammation and subsequent mesenteric con- Inflammatory ascites
traction of intestine to right side of abdominal cavity
edema, and crepitus. The pelvic examination in women should toneum or the intestinal lumen), preexisting anemia, or bleeding.
check for vaginal discharge or bleeding, cervical discharge or bleed- An elevated white blood cell (WBC) count is indicative of an in-
ing, cervical mobility and tenderness, uterine tenderness, uterine flammatory process and is a particularly helpful finding if associated
size, and adnexal tenderness or masses. Although a carefully per- with a marked left shift; however, the presence or absence of leuko-
formed pelvic examination can be invaluable in differentiating non- cytosis should never be the single deciding factor as to whether the
surgical conditions (e.g., pelvic inflammatory disease and tubo- patient should undergo an operation. A low WBC count may be a
ovarian abscess) from conditions necessitating prompt operation feature of viral infections, gastroenteritis, or NSAP. Other tests, such
(e.g., acute appendicitis), the possibility that a surgical condition is as C-reactive protein assay, may be useful for increasing confidence
present should not be prematurely dismissed solely on the basis of a in the diagnosis of an acute inflammatory condition. An important
finding of tenderness on pelvic or rectal examination. consideration in the use of any such test is that derangements devel-
op over time, becoming more likely as the illness progresses; thus,
serial examinations might be more useful than a single test result
Investigative Studies obtained at an arbitrary point. Indeed, for the diagnosis of acute ap-
Laboratory tests and pendicitis, serial observations of the leukocyte count and the C-re-
imaging studies rarely, if active protein level have been shown to possess greater predictive
ever, establish a definitive value than single observations.33
diagnosis by themselves; Serum electrolyte, blood urea nitrogen (BUN), and creatinine
however, if used in the cor- concentrations are useful in determining the nature and extent of
rect clinical setting, they can fluid losses. Blood glucose and other blood chemistries may also be
confirm or exclude specific helpful. Liver function tests (serum bilirubin, alkaline phosphatase,
diagnoses suggested by the history and the physical examination. and transaminase levels) are mandatory when abdominal pain is
suspected of being hepatobiliary in origin. Similarly, amylase and li-
LABORATORY TESTS
pase determinations are mandatory when pancreatitis is suspected,
In all patients except those in extremis, a complete blood count, though it must be remembered that amylase levels may be low or
blood chemistries, and a urinalysis are routinely obtained before a normal in patients with pancreatitis and may be markedly elevated
decision to operate.The hematocrit is important in that it allows the in patients with other conditions (e.g., intestinal obstruction,
surgeon to detect significant changes in plasma volume (e.g., dehy- mesenteric thrombosis, and perforated ulcer).
dration caused by vomiting, diarrhea, or fluid loss into the peri- Urinalysis may reveal red blood cells (RBCs) (suggestive of renal

13. © 2006 WebMD, Inc. All rights reserved. ACS Surgery: Principles and Practice
5 GASTROINTESTINAL TRACT AND ABDOMEN 1 Acute Abdominal Pain — 13
or ureteral calculi),WBCs (suggestive of urinary tract infection or formed, and a working or presumed diagnosis is generated. Once a
inflammatory processes adjacent to the ureters, such as retrocecal working diagnosis has been established, subsequent management
appendicitis), increased specific gravity (suggestive of dehydration), depends on the accepted treatment for the particular condition be-
glucose, ketones (suggestive of diabetes), or bilirubin (suggestive of lieved to be present. In general, the course of management follows
hepatitis). A pregnancy test should be considered in any woman of four basic pathways [see Management: Surgical versus Nonsurgical
childbearing age who is experiencing acute abdominal pain. Treatment, below], depending on whether the patient (1) has an
Electrocardiography is mandatory in elderly patients and in pa- acute surgical condition that necessitates immediate laparotomy,
tients with a history of cardiomyopathy, dysrhythmia, or ischemic (2) is believed to have an underlying surgical condition that does
heart disease. Abdominal pain may be a manifestation of myocar- not necessitate immediate laparotomy but does call for urgent or
dial disease, and the physiologic stress of acute abdominal pain can early operation, (3) has an uncertain diagnosis that does not neces-
increase myocardial oxygen demands and induce ischemia in pa- sitate immediate or urgent laparotomy and that may prove to be
tients with coronary artery disease. nonsurgical, or (4) is believed to have an underlying nonsurgical
condition.
IMAGING
It must be emphasized that the patient must be constantly reeval-
Until relatively recently, initial radiologic evaluation of the patient uated (preferably by the same examiner) even after the working di-
with acute abdominal pain included plain films of the abdomen in agnosis has been established. If the patient does not respond to treat-
the supine and standing positions and chest radiographs.34 Current- ment as expected, the working diagnosis must be reconsidered, and
ly, CT scanning (when available) is generally considered more likely the possibility that another condition exists must be immediately en-
to be helpful in most situations.35,36 Still, there remain some situa- tertained and investigated by returning to the differential diagnosis.
tions in which plain films may be a more useful and safe form of in-
vestigation—as, for example, when a strangulating obstruction is
thought to be the most likely diagnosis and plain films are used for Management: Surgical versus Nonsurgical Treatment
rapid confirmation. If the diagnosis of strangulating obstruction is in
ACUTE SURGICAL AB-
doubt, however, CT scanning—particularly with the newer genera-
DOMEN
tions of scanning instruments—is useful for making a definitive di-
agnosis and for identifying clinically unsuspected strangulation.37-39 A thorough but expedi-
When performed in the correct clinical setting, imaging studies tious approach to patients
may confirm diagnoses such as pneumonia (signaled by pulmonary with acute abdominal pain
infiltrates); intestinal obstruction (air-fluid levels and dilated loops of is essential because in some
bowel); intestinal perforation (pneumoperitoneum); biliary, renal, or patients, action must be
ureteral calculi (abnormal calcifications); appendicitis (fecalith); in- taken immediately and
carcerated hernia (bowel protruding beyond the confines of the peri- there is not enough time for an exhaustive evaluation. As outlined
toneal cavity); mesenteric infarction (air in the portal vein); chronic (see above), such an approach should include a brief initial assess-
pancreatitis (pancreatic calcifications); acute pancreatitis (the so- ment, a complete clinical history, a thorough physical examination,
called colon cutoff sign); visceral aneurysms (calcified rim); retroperi- and targeted laboratory and imaging studies.These steps can usual-
toneal hematoma or abscess (obliteration of the psoas shadow); and ly be completed in less than 1 hour and should be insisted on in the
ischemic colitis (so-called thumbprinting on the colonic wall). evaluation of most patients. In most cases, it is wise to resist the
Although in most settings, CT is the preferred modality for pri- temptation to rush to the operating room with an incompletely eval-
mary evaluation of acute abdominal pain, there are certain settings uated, unprepared, and unstable patient. Sometimes, the anxiety of
in which US should be considered.When gallstones are considered the patient or the impatience of the health care providers requesting
a likely diagnosis, US is more apt to be diagnostic than CT is, given the surgeon’s consultation creates an unwarranted feeling of ur-
that about 85% of gallstones are not detectable by x-rays. In disor- gency. Often, however, the anxiety or impatience is on the part of
ders of the female genitourinary tract, US is also quite sensitive and the surgeon and, if indulged, may be a cause of subsequent regret.
specific for diagnoses such as ovarian cyst, fallopian tube pregnan- There are very few abdominal crises that mandate immediate
cy, and intrauterine pregnancy. Although there are reassuring re- operation, and even with these conditions, it is still necessary to
ports that the risks of radiation from CT scanning can be managed spend a few minutes on assessing the seriousness of the problem
in children and pregnant women with abdominal pain,40,41 there re- and establishing a probable diagnosis. Among the most common of
main theoretical concerns regarding the teratogenicity of the radia- the abdominal catastrophes that necessitate immediate operation
tion dose.42 Accordingly, it would seems prudent to consider US are ruptured AAAs or visceral aneurysms, ruptured ectopic preg-
the preferred initial imaging test for such patients. In these circum- nancies, and spontaneous hepatic or splenic ruptures.The relative
stances, CT is employed only if the diagnosis remains unresolved rarity of such conditions notwithstanding, it must always be re-
and if the potential delay in diagnosis (from not obtaining a CT membered that patients with acute abdominal pain may have a pro-
scan) is likely to cause harm. gressive underlying intra-abdominal disorder causing the acute pain
and that unnecessary delays in diagnosis and treatment can ad-
versely affect outcome, often with catastrophic consequences.
Working or Presumed
Diagnosis SUBACUTE SURGICAL AB-
DOMEN
The tentative differential
diagnosis developed on the When immediate opera-
basis of the clinical history is tion is not called for, the
refined on the basis of the physician must decide
physical examination and whether urgent laparotomy
the investigative studies per- or nonurgent but early op-