THE ABDOMEN REVEALED
| ABDOMINAL ULTRASONOGRAPHY AND FOCUSED ABDOMINAL SONOGRAPHY IN TRAUMA
(FAST)—Joseph P. Wood, MD, Assistant Professor and Vice-Chair, Department of Emergency Medicine,
Mayo Clinic, Scottsdale, AZ
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| Historical perspective: opposition from radiologists to use of ultrasonography (US) by nonradiologists; American
Medical Association (AMA) Resolution 802 set policy that US could be used by many medical specialists, including
emergency physicians, and that credentialing for use of US should be done by departments in local
hospitals
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| Case: 70-yr-old man brought to emergency department (ED) by ambulance after choking spell at restaurant; bystander
performed Heimlich maneuver before arrival of paramedics; patient alert when brought in; vital signs unremarkable;
hypertension only past medical problem; physical examination normal, except for minimal
abdominal tenderness; choking prompted by syncope; FAST examination revealed 8-cm aortic aneurysm; patient
sent to operating room (OR)
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| Case: male patient with stab wound to left chest; vital signs normal and appearance unremarkable; FAST examination
showed fluid-filled pericardial sac, indicating right ventricle undergoing collapse; diagnosis of hemopericardium
with impending cardiac tamponade made, even though patient not short of breath; patient sent to
OR
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| Case: 84-yr-old man involved in single-vehicle accident; patient hypotensive and “shocky”; FAST examination
negative for fluid in Morrison’s pouch, but showed weak “quivering” heart (not characteristic of hypovolemia,
which usually causes “wildly flailing” heart); electrocardiography positive for acute myocardial
infarction; patient sent for catheterization
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| FAST examination: indications—blunt trauma; penetrating trauma; what to look for—fluid, eg, in Morrison’s
pouch, fluid in splenorenal window
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 | Windows (views): subxiphoid area—look for fluid in pericardial sac; determine overall contractility of heart;
right upper quadrant (RUQ)—area between Glisson’s capsule and Gerota’s fascia (peritoneal reflection,
Morrison’s pouch); most likely to see free fluid from any source in peritoneum in RUQ view; subcostal—
slide probe up into subcostal window; probe sends out 1- to 1.5-mm beam; may need to almost lay probe
down on abdomen when trying to fan beam through heart; beam goes through left lobe of liver (good acoustic
window, ie, no scatter by adjacent structures); right ventricle seen first; looking for anechoic area (looks black
because fluid does not reflect beam); parasternal long—alternative to subcostal view; indicated in patients
with large amount of abdominal fat; “parasternal” because probe placed along sternum; “long” because beam
oriented to long axis of heart; coronal view—first right side, looking for interface between kidney and liver;
Morrison’s pouch peritoneal reflection between Glisson’s capsule and Gerota’s fascia, area where fluid likely
to accumulate (need 400-500 mL of fluid to visualize); flip probe to get mirror-image view on left side; examine
spleen and kidney, looking for fluid around those organs; suprapubic—examine in transverse and sagittal
planes by turning probe 190°; tip of bladder points to level of cervix in women; look for fluid in posterior cul-
de-sac; turn probe to get transverse view; uterus right below bladder; look for fluid between uterus and rectum;
floating loops of bowel indicate presence of fluid
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| Case: 23-yr-old man with gunshot wound to buttocks transferred to trauma center; stable for 6 hr, but condition
deteriorates within 1 hr of transfer; FAST examination revealed significant amount of fluid in Morrison’s
pouch; bullet had ricocheted off pelvis, causing intra-abdominal injury; patient had wildly flailing heart characteristic
of hypovolemia and fair amount of fluid in pericardial sac
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| Effectiveness of FAST: highly sensitive and specific for finding fluid in abdominal area; fluid accumulation
not necessarily indication of intra-abdominal bleeding (eg, could be inflammatory fluid); can perform FAST
quickly after minimal experience; can use to screen patients to determine whether computed tomography (CT)
needed
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| Abdominal aortic aneurysm (AAA): use transverse plane to scan from top to bottom; subxiphoid window best
to visualize aorta because of acoustic view through left lobe of liver; below this window, visualizing aorta becomes
more difficult because of bowel gas; rock transducer back and forth to obtain better view; aorta not identified
in ≈10% of cases; can see celiac artery branching; avoid using longitudinal plane (may miss saccular
aneurysm)
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| RIGHT LOWER QUADRANT PAIN IN WOMEN —Pamela L. Dyne, MD, Associate Professor of Medicine,
David Geffen School of Medicine at the University of California, Los Angeles, and Residency Director, UCLA/
Olive View Medical Center, Los Angeles
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| Case: 29-yr-old obese woman returns to ED complaining of increasing right lower quadrant (RLQ) pain and requesting
refill of hydrocodone (Vicodin); seen in ED 7 days before, and US showed right ovarian cyst; at that
visit, patient discharged with nonsteriodal anti-inflammatory drugs (NSAIDs) and hydrocodone; good response,
but now complaining of more pain and fever for 2 days; patient hypertensive, tachycardic, and febrile;
physical examination found some RLQ tenderness, positive bowel sounds, and soft abdomen without
guarding or rebound; pelvic examination showed moderate right adnexal tenderness but otherwise normal
with minimal discharge; guaiac test negative; patient had no flank tenderness; high-risk situation with potentially
life-threatening causes in differential diagnosis; patient has challenging history; symptoms vague and
overlapping; physical examination difficult; several diagnostic tests available, and unclear where to start
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| Abdominal pain: visceral pain—caused by stretching of smooth muscle wall of hollow organs or capsular
wall of solid organs; every organ has bilateral pain fibers that enter spinal cord at multiple levels, resulting in
vague symptoms of pain and vague physical findings; pain diffuse, “crampy,” poorly localized, and frequently
midline; pain results from inflammation of organ; somatic pain—caused by ischemia, inflammation,
or stretching of parietal peritoneum; pain fibers enter spinal cord at specific place; pain constant, sharp, and
well-localized, with focal tenderness; this type of pain develops as disease progresses and inflammation extends
outside organ into parietal peritoneum; referred pain—visceral nerve fibers from diseased organ enter
spinal cord at same level as somatic nerve fibers from other location (area of referred pain), eg, shoulder pain
with cholecystitis, inner thigh pain with pelvic inflammatory disease (PID) or appendicitis, groin pain with renal
colic; narcotics—do not make physical examination unreliable or diagnosis more difficult; pain medication
can make examination more reliable and focused by relaxing abdominal wall musculature, thus allowing
better localization of pain; consider short-acting intravenous narcotic (eg, fentanyl) to allow for reassessment
of symptoms over time (may need repeat dosing); once diagnosis made, can use longer acting narcotic
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| Differential diagnosis for case: consider ectopic pregnancy, appendicitis, adnexal torsion, PID or right-sided
tubo-ovarian abscess (TOA), and undifferentiated abdominal pain
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| Ectopic pregnancy: must be ruled out (negative history of pregnancy or unprotected sex unreliable); obtain
urine bedside pregnancy test (99.4% sensitivity; accuracy of test depends on serum β-human chorionic gonadotropin
(hCG) level; test positive when β-hCG 10 to 50 mIU/mL; lower β-hCG level or dilute urine can result
in false-negative test; risk factors—include previous ectopic pregnancy, tubal infection, tubal surgery, use of
intrauterine device, history of infertility for >2 yr, age >35 yr, diethylstilbestrol (DES) exposure, smoking,
and frequent douching; 50% of women with ectopic pregnancies have ≥1 risk factor (as do 25% of women
with threatened spontaneous abortion); “all pregnant women have ectopic pregnancy until proven otherwise”—
no combination of history and physical findings reliably excludes diagnosis; all patients need work-up; helpful
clinical findings include peritoneal signs, unilateral pain and tenderness, and cervical motion tenderness
(CMT); clinical features that make diagnosis more unlikely include open internal cervical os with passage of
products of conception (miscarriage), fetal heart tones by Doppler US, uterus >8 cm, or midline pain; work-
up—obtain quantitative β-hCG (no cutoff too low to get US; most ectopics associated with relatively low β-
hCG); β-hCG <1000 mIU/mL associated with 4-fold higher relative risk for ectopic pregnancy; order pelvic
US; US diagnostic in 75% of ED patients and in 69% of ectopic cases; US more likely diagnostic in patients
with higher β-hCG levels; if β-hCG <1500 mIU/mL, US indeterminate and should be repeated in 48 hr; if
pregnancy intrauterine, β-hCG should keep increasing
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| Adnexal torsion: risk factors—reproductive age, benign cysts or neoplasms (most >5 cm), history of ovarian
mass or cysts, (history of PID), use of ovulation induction agents, hypothyroidism, history of pelvic surgery,
pregnancy; clinical history—recent vigorous activity; nausea and vomiting; stabbing pain or sudden, sharp
pain in lower abdomen (can radiate to back, flank, or groin); peritoneal signs; fever; palpable adnexal mass;
workup—obtain pelvic US; look for cystic or solid adnexal mass and free fluid; ovary may be hemorrhagic or
normal; color flow Doppler—specificity 100%, ie, if positive, diagnosis made; sensitivity 40% overall, ie, normal
result does not rule out diagnosis; higher sensitivity associated with ovulation induction agents and pregnancy;
normal result can delay care and management
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| Pelvic inflammatory disease: diagnostic criteria—Centers for Disease Control and Prevention (CDC) criteria
require risk factor and tenderness on pelvic examination without another obvious cause; supportive findings—
mucopurulent vaginal discharge, elevated C-reactive protein or erythrocyte sedimentation rate, fever, white
blood cells (WBCs) on wet mount; TOA—consider pelvic US if physical examination technically difficult
(eg, obese patient), if patient has fever and peritoneal signs, if pelvic examination reveals asymmetric or unilateral
tenderness, or if patient fails treatment for PID; laboratory testing not necessary (tests nonspecific, elevation
likely, and normal result does not rule out diagnosis); criteria for admission for PID—patient too sick to
go home (recommend TOA workup); surgical emergency not ruled out; outpatient treatment fails; TOA or abscess
present or possible; concomitant pregnancy; patient immunocompromised; adolescent patients
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| Appendicitis: all patients with abdominal pain have appendicitis until proven otherwise (ie, alternative diagnosis
made or appendicitis ruled out); clinical findings to support diagnosis include peritoneal signs, fever, and elevated
WBC count; however, these findings not sensitive or specific for peritonitis or appendicitis; 20% of
patients with appendicitis have normal WBC count; high incidence of misdiagnosis in these patients if diagnosis
based only on clinical evaluation; significant overlap between clinical features of appendicitis and PID;
CMT, vaginal discharge, and positive urinalysis can be present in patients correctly and incorrectly diagnosed
with appendicitis; get further testing in patient with risk factor for appendicitis; imaging studies—poor sensitivity
and specificity of US for appendicitis; CT associated with greater sensitivity and specificity; accuracy of
CT higher if appendicitis suspected, as opposed to trying to rule out appendicitis; CT also may provide alternative
diagnosis
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| Management algorithm for female patient with RLQ pain: get urine pregnancy test, complete blood
count, urinalysis, and perform history and physical examination; if β-hCG positive, proceed with protocol to
diagnose or exclude ectopic pregnancy (obtain US for diagnosis; if US not diagnostic, discharge patient with
follow-up instructions); if β-hCG negative, pay attention to pain characteristics; ask patient about vaginal and
pelvic history, including dyspareunia, medication history and use of ovulation induction agents, pelvic surgeries,
and ovarian mass; during physical examination, pay attention to abdomen; if peritoneal signs present,
determine if diffuse or focal; after gathering information from tests, history, and physical examination, and if
diagnosis not firm, decide whether problem likely to need surgical or gynecologic management; if diagnosis
PID, do not need further testing; if diagnosis probably surgical problem (eg, appendicitis), diagnostic testing
required; obtain CT; if CT normal, and patient still symptomatic, get US or possibly admit for observation; if
patient not symptomatic, discharge with instructions for follow-up
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| Undifferentiated abdominal pain: use this diagnosis if cause of pain unclear and condition resolves; provide
specific instructions at discharge for return if symptoms recur; have follow-up plan
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Suggested Reading
Blaivas M: Emergency diagnostic paracentesis to determine intraperitoneal fluid identity discovered on bedside
ultrasound of unstable patients. J Emerg Med 29:461, 2005; Close RJ et al: Reliability of bimanual pelvic
examinations performed in emergency departments. West J Med 175:240, 2001; Jang T et al: Minimum training
for right upper quadrant ultrasonography. Am J Emerg Med 22:439, 2004; Kalliakmanis V et al: Acute appendicitis:
the reliability of diagnosis by clinical assessment alone. Scand J Surg 94:201, 2005; Lee CC et al:
Routine versus selective abdominal computed tomography scan in the evaluation of right lower quadrant pain: a
randomized controlled trial. Acad Emerg Med 14:117, 2007; Ma OJ et al: Anechoic stripe size influences accuracy
of FAST examination interpretation. Acad Emerg Med 13:248, 2006; Menaker J et al: Ultrasound-diagnosed
cardiac tamponade after blunt abdominal trauma-treated with emergent thoracotomy. J Emerg Med 32:99,
2007; Rose JS: Ultrasound in abdominal trauma. Emerg Med Clin North Am 22:581, 2004.
Educational Objectives
| The goal of this activity is to educate the listener about abdominal ultrasonography, including focused abdominal
sonography in trauma (FAST) and evaluating right lower quadrant (RLQ) pain in women. After hearing and
assimilating this program, the clinician will be better able to:
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| 1. Discuss practical applications of ultrasonography by emergency physicians at the bedside.
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| 2. List the views used in FAST exam and where to look for fluid in these areas.
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| 3. Evaluate a patient with RLQ pain.
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| 4. Describe the types of abdominal pain.
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| 5. Discuss the differential diagnosis for RLQ pain.
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Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant
financial relationship with the manufacturer or provider of any commercial product or service discussed.
For this issue the faculty reported nothing to disclose.
Acknowledgements
Dr. Wood was recorded at Emergency Medicine 2006—Moving Forward, sponsored by the Mayo Clinic College of
Medicine and Mayo School of Continuing Medical Education, held March 30-April 1, 2006, in Scottsdale, AZ. Dr.
Dyne was recorded at Advances in Emergency Medicine and Primary Care, sponsored by the David Geffen School of
Medicine at the University of California, Los Angeles, Olive-View/UCLA Medical Center, and the American College
of Emergency Physicians, State Chapter of California, Inc., held April 19-21, 2006, in Las Vegas, NV. The Audio-Digest
Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.
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