Eastern Virginia Medical School
Emergency Medicine Journal Club
P: In patients requiring abdominal CT for non-traumatic abdominal pain
I: Is withholding the use of oral contrast
C: Compared to routine use of oral contrast
O: Associated with a decrease in diagnostic accuracy?
Article Study Patient Key Results Conclusions Limitations
A systematic Review of 23 3,474 Oral contrast The broader -Studies all
review of prospective patients no oral use of CT vary in design,
whether oral (19) and undergoing contrast, without oral inclusion and
contrast is retrospective CT sensitivity contrast may exclusion
necessary (4) studies scanning 92% vz 95%, be a useful criteria, CT
for the assessing CT for specificity 94% approach in scanning
computed scan for the suspected vs 97%, PPV suspected technique,
tomography diagnosis of appendicitis 89% vs 97%, appendicitis radiologic
diagnosis of appendicitis NPV 96% vs criteria, and
appendicitis 96% scan fields.
in adults. -Unenhanced
Anderson et CT had
al. 2005. superior
Journal of compared with
Surgery oral contrast.
Rapid CT Retrospective 173 59 CT Using IV -35 eligible
diagnosis of review of patients 17 diagnoses of contrast alone patients were
acute patient or older acute is highly lost to follow
appendicitis studies with IV appendicitis sensitive and up and could
with IV presenting to contrast were made, 56 specific in have
contrast the enhanced of which were confirming conceivably
material. emergency CT with the histologically and excluding presented
Mun et al. room over an word verified. 114 acute elsewhere with
2005. 8 month appendicitis CT diagnoses appendicitis. appendicitis.
Emergency period for in either were negative -Initial study
Radiology abdominal the clinical for retrieval
pain indication appendicitis. excluded all
or Corresponding cases where
radiologic to a sensitivity appendicitis
impression of 100%, was not
specificity of specifically
97%, PPV of used, possibly
95%, and NPV eliminating
of 100% atypical
Prospective Prospective 118 For 21 patients NECT can be -No true final
comparison study of patients (79%) there as accurate diagnosis was
of helical CT patients presenting was clinically as CECT in made in many
of the presenting to with acute significant the diagnosis of the cases
abdomen the abdominal disagreement of many that did not go
and pelvis Emergency pain between CECT etiologies of for surgery or
without and Room over a already and NECT abdominal definitive
with oral 13 month undergoing interpretations. pain, and post follow up.
contrast in period a CT After unblinded hoc analysis -The amount
assessing undergoing a abdomen/ consensus suggests that of clinical
acute CT abdomen/ pelvis, of review, 18 of discrepancies information
abdominal pelvis. which 100 the 21 were are largely may have
pain in adult completed primarily due to differed and
Emergency the related to interobserver influenced
Department protocol. interobserver variation interpretations.
patients. Lee variability. rather than -Logistical
et al. 2006. technique of factors limited
Emergency bowel sampling to 2
Radiology opacification. cases per
CT scan for Retrospective 661 IV contrast No significant -Included
suspected review of all patients only (54.2%) difference, CT inpatients
acute hospital over a 3 sensitivity of contrast only.
abdominal inpatients month 92.5%. administration -Excluded
process: who period at 1 IV and oral in critically ill those
Impact of underwent hospital (22.2%) hospitalized suspicious for
combinations urgent or sensitivity of patients is not appendicitis or
of IV, oral, emergent 94.6%. necessary to diverticulitis.
and rectal abdominal/ Unenhanced accurately -Cannot make
contrast. Hill pelvic CT CT (16.2%) diagnose an conclusions
et al. 2010. with any sensitivity of acute regarding
World combination 92.5%. abdominal clinical
Journal of of contrast, Oral contrast process. decisions
Surgery IV, oral, only (7%) influencing the
rectal, or sensitivity of use of the
unenhanced 93.5%. various
for a contrast
Diagnostic Systematic 1,060 Pooled data The - a number of
Accuracy of review patients showed a diagnostic studies were
Noncontrast including 7 who sensitivity of accuracy of omitted
Computed studies, that underwent 92.7% and noncontrast because they
Tomography assessed the a specificity of CT for the wre unable to
for diagnostic noncontrast 96.1% diagnosis of confirm length
Appendicitis accuracy of enhanced acute of follow up
in Adults: A noncontrast CT for appendicitis in which may
Systematic CT for acute suspected the adult have sig
Review. appendicitis appendicitis population is changed
Hilbczuk et in adults adequate for sen/spec if
al. 2010. clinical included
Annals of decision - no
Emergency making in the comparison
Medicine ED setting. with contrast
Clinical Bottom Line: Withholding the use of oral contast in the evaluation of non-
traumatic acute abdominal pain in the Emergency Department setting does not
significantly reduce diagnostic accuracy. However, increased experience and
cooperation with each institution’s Radiology Department will play a critical role in the
implementation of such a protocol.
Effect of oral contrast for abdominal computed tomography on emergency
department length of stay. Schuur et al. 2009. Emergency Radiology.
Retrospective cohort of adult patients visiting an academic ED over 13 wk period.
20,464 visits, of which 1,806 underwent an CTAP. Half way through the study period a
protocol change was implemented, in which routine use of OC was eliminated for
patients undergoing CTAP. Among all ED visits there was no change in LOS. Among
ED visits where a CTAP was performed, LOS decreased by 30 minutes (324 to 297).
This only included a 30% (42.5% to 12.2%) absolute reduction in OC usage, since many
of the CTAPs at that institution were for trauma and were already done without OC.
Patient encounter time intervals in the evaluation of emergency department patients
requiring abdominopelvic CT: oral contrast versus no contrast. Huynh et al. 2004.
Retrospective evaluation of all adult patients who had a CTAP for abominal pain during a
30 day period at a high volume regional medical center. Excluded trauma, pediatrics, and
pregnant. 43 underwent NECT for abdominal pain other than R/O renal colic and 81
underwent CECT (oral only). Ordering CT to scan 104 to 172 min, arrival to disposition
358 to 599min.