Transcript Gender Bias in Cardiovascular Disease

Discerning the Helpful From
the Hedge: Imaging Tips for
Abdominal Emergencies
Angela M. Mills, MD
March 5, 2012
Department of Emergency
Medicine
University of Pennsylvania Health System
Disclosures
None related to this talk
n Allere, Inc.
– Research Funding
n
Siemens Health Care Diagnostics
– Research Funding
n
EM Clinics of North America
– Honorarium
Hedge (hĕj)
n.
4. An intentionally noncommittal or
ambiguous statement.
v.intr.
3. To avoid making a clear, direct
response or statement.
The American Heritage® Dictionary of the English Language
The Hedge
Overview
Epidemiology
Right upper quadrant pain
Pelvic pain
Right lower quadrant pain in
pregnancy
Contrast for suspected appendicitis
Over 8 million visits for abdominal pain in 2006
13.9% all ED pts
Kocher et al. Ann Emerg Med. 2011.
Almost 10x higher likelihood of CT in 2007 than 1996
Kocher et al. Ann Emerg Med. 2011.
Cat Scan
RUQ Pain:
Is It Acute Cholecystitis?
Ultrasound
“…Recommend HIDA scan if there is
concern for acute cholecystitis”
Acute Cholecystitis
EMBU comparable to Rad
– Sensitivity 87% vs. 83%
– Specificity 82% vs. 86%
– Prior studies sensitivity 84-98%
CT sensitivity 75%
– Perforation, emphysematous chole,
alternative diagnoses
Summers et al. Ann Emerg Med. 2010.
Privette et al. EMCNA. 2011.
HIDA
Nonfilling of GB
suggestive of AC
– GB normally visualized
within 30 mins
Sensitivity 90-100%
Specificity 85-90%
Privette et al. EMCNA. 2011.
Blaivas et al. J Emerg Med. 2007.
99 pts, ED US and HIDA
Agreement 77%
80% (12/15) +HIDA but –US,
path agreed with US
5 pts with normal HIDA but +US,
path agreed with US
Blaivas et al. J Emerg Med. 2007.
Other HIDA Indications
Symptoms of biliary dyskinesia
(chronic acalculous cholecystitis)
Biliary tree anomalies
Evaluation of bile leak post chole
Sick ICU patient
– GN sepsis and unreliable exam
– Unexplained leukocytosis on TPN
Lambie et al. Clin Rad. 2011.
HIDA Limitations
Does not image other structures
High bilirubin (>4.4 mg/dL) can ↓ sensitivity
Recent eating or fasting for 24 hrs
False negatives (filling in 30 min) in 0.5%
– Filling between 30-60 mins associated with falsenegative rates of 15-20%
False-positive results (10-20%)
Blaivas et al. J Emerg Med. 2007.
Gallstones
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Pelvic Pain:
Is It Ovarian Torsion?
Computed Tomography
“…Recommend US if there is concern
for ovarian torsion”
Chiou et al. J US Med. 2007.
100% OT had abnormal ovary on CT
CT with normal ovaries rules out torsion
Moore et al. Emerg Rad. 2009.
Moore et al. Emerg Rad. 2009.
US for Ovarian Torsion
Abnormal flow
– Sensitivity 44%, Specificity 92%
– PPV 78%, NPV 71%
Accuracy 71%
Bar-On et al. Fertil Steril. 2010.
Chiou et al. J US Med. 2007.
US for TOA
Sensitivity 56-93%
Specificity 86-98%
Only prospective study showed
Sensitivity 56%, Specificity 86%
Lee et al. J Emerg Med. 2011.
Tukeva et al. Rad. 1999.
CT for TOA
No studies to evaluate Sens/Spec
Ovarian masses, dilated tubes, free
fluid equally seen CT and US
Fat stranding better seen on CT
May be more difficult to
differentiate pyosalpinx from T-O
complex or abscess by CT
Horrow et al. US Quart. 2004.
CT for TOA
Hiller et al. JRM. 2005.
Cat Scan
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RLQ Pain in Pregnancy:
Is It Appendicitis?
US for Appendicitis
“…Recommend MRI if there is concern
for acute appendicitis”
US for Appendicitis
Systematic review 14 studies (adults)
– Sensitivity 81%, Specificity 80%
Appendix not seen 25-35% of time
– Positive when diameter >6-7mm
False negatives with perforation,
retrocecal or tip inflammation only
Eresawa et al. Ann Int Med. 2004.
Horn et al. EMCNA. 2011.
Kessler et al. Rad. 2004.
US for Appendicitis
Systematic review
Imaging after normal or inconclusive
US in pregnancy
– CT: Sensitivity 86%, Specificity 97%
– MRI: Sensitivity 80%, Specificity 99%
Basaran et al. Ob Gyn Surv. 2009.
MRI Appendicitis in Pregnancy
MRI vs. CT in Pregnancy
MRI has NPV 98% for acute abd pain
Both show alternative diagnoses
Retrospective study 1998-2005 greater
increase in abd CT in pregnancy
– 22%/yr/1,000 deliveries vs. 13%/yr
– Suspected appy most common indication
Oto et al. Abd Imaging. 2009.
Goldberg-Stein et al. Am J Roentgenol. 2011.
No consensus for imaging algorithm
for abd pain in pregnancy
Radiology survey
– 96% respondents perform CT when
benefit/risk ratio is high
– MRI preferred 1st trimester
– CT preferred 2nd / 3rd trimesters
Jaffe et al. Am J Roentgenol. 2007.
Suspected Appendicitis:
Is Contrast Needed?
Contrast
Oral
– Limits resp misregistration, motion artifacts
• Development of fast multidetector CT
– Protocols: 60-90 mins to opacify bowel
IV
– Highlights differences btwn soft tissues
– Risk of CIN, allergic reaction
Holmes et al. Ann EM. 2004.
Stuhlfaut et al. Rad. 2004.
Retrospective, 183 pts
– 81 oral contrast, 102 no oral contrast
– Stat sig increased ED LOS
• 358 vs. 599 min, p<0.001
– Difference of 241 min >> 90 min
Huynh et al. Emerg Rad. 2004.
Systematic review of 23 studies
– 19/23 prospective, total 3474 patients
• 1510 patients no oral contrast
– Final dx by path or clinical follow up
Anderson et al. Am J Surg. 2005.
7-study systematic review
– 1060 patients
– Final dx at surgery or min 2 week f/u
– Noncontrast = no oral or IV
Sensitivity 93%, Specificity 96%
– Comparable to prior published reviews
Hlibczuk et al. Ann Emerg Med. 2010.
Questions
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