Transcript Pediatric Appendicitis A Clinical Pathway

Pediatric Appendicitis
A Clinical Pathway
James Reingold, M.D.
November 3,4 2011
James Reingold, M.D.
• Medical Director, Cardon Children’s ED
• Board Certified, PEM (Peds, Peds ER)
• Member of the defunct ED Order Set
Workgroup
– Goals of standardizing care to “best practice”
and reducing risk
• Member of Peds CCG
• 4+ years with “The Bannerman”
Risk Considerations
• “The ED is often crowded, waits are long
and privacy is limited. The ED
environment is often one of excessive
noise, high volume, and extreme pressure
and stress.”
• Especially weekends, holidays, evenings
and nights spawn litigation (80%!)
• The ED accounts for 45% of peds cases
Risk Considerations
• By age 6 yrs, appendicitis is the 2nd most
common diagnosis claim
• Insurance co. complaints about Banner
prolonged LOS and perforation rate
• Testicular Torsion is #3 for boys 12-17 yrs,
do your TSG course!
Pediatric Appendicitis
• The most common surgical emergency in
children
• 70K appendectomies each yr in the US
• Appendicitis is rare before age 1, when
the appendix is “funnel shaped”
• Appendicitis under age 4 results in
perforation rates of 80-100%
Pediatric Appendicitis
• Appendicitis incidence peaks at age 10-20
yrs because of lymphoid follicle
hyperplasia, but perforation rate is only
10-20%
• Taken together, children 0-17 have
perforation rate of 33%
Radiation Concerns
• Concern over missed appendicitis led to
widespread use of CT
• A clinical guideline at Harvard pushing CT
imaging decreased both the negative
appendectomy rate and admission for
serial abdominal exams
– Perforation rate was unchanged
– CT rate increased from 5% to 60%
Radiation Concerns
• Adult CT is more common but the rate of
increase is larger among children,
primarily because CT is now faster and
does not require sedation
• “The major growth area in CT use for
children has been the presurgical
diagnosis of appendicitis.”
Radiation Concerns
• Children are at higher risk of radiation-induced
carcinogenesis because of greater sensitivity to
radiation as well as a longer life span to allow
cancers to develop
– They are also more likely to undergo further CT
imaging as they age
– Lifetime attributable risk of death from cancer from a
SINGLE abd CT for a 5 y/o is 0.09%
– Of 600K children/yr who undergo CT, 500 will develop
cancer (slightly less than 1/10,000 risk)
Radiation Concerns
• Atomic Bomb data
– 25,000 survivors received a dose less than 50
mSv, mean dose 40 mSV
– A single CT Abd study delivers 45-90 mSv
radiation depending on age
– 1.5-2% of all cancer in the US now
attributable to CT imaging
Radiation Concerns
• Is there a difference between “clean”
radiation from GE and “dirty” radiation
from an atomic bomb?
• 400,000 radiation workers exposed to 20
mSv
– Mortality from cancer correlated to radiation
dose within 5-150 mSv
– Correlated with A-bomb data
Alvarado Score
• This study from 1986 published in Annals of
Emergency Medicine was a retrospective review
of 305 surgical admissions to Nazareth Hospital
in Philadelphia
– Charts pulled over 24 mos, 1975-76
• 74% prevalence of appendicitis!
• Study Goal: Approach pts in a rational manner
•
using a simple diagnostic score for observation
vs surgery
Discussed a MANTRELS score to aid in diagnosis
MANTRELS
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Migration of pain to the RLQ
Anorexia
Nausea/vomiting
Tenderness in the RLQ
Rebound tenderness
Elevation of temp
Leukocytosis
Shfit of WBC count
Evaluation of Alvarado Score
• Bond, et al. Annals of Emergency
Medicine, 1990
– 1st to stratify the score to specified risk levels
– Among children with a score of 4 or lower,
none had appendicitis
– Other studies report negative likelihood ratio
of 0.05
• (9% x 0.05=0.45%)
– Score performed best among older children.
Evaluation of Alvarado Score
• Three prospective studies show a score of 7 or
higher increases the likelihood of appendicitis 4x
(95% CI=3-5)
– So 9% x 4=36%
• Macklin, et al. Annals of the Royal College of
Surgeons of England.
– Performance unchanged by dropping S (left shift)
– “Modified Alvarado,” this is what we are using
Clinical Practice Guidelines
• Harvard has received the most attention
• Surgical consultation BEFORE imaging
– The Heidi Cox, MD memorial ED consult
• If classic, to OR without labs
• If concerning, labs
• If imaging negative, home
• Age <4 excluded
Clinical Practice Guidelines
• Harvard Results
– 34% appendicitis prevalence
– 60% presented in 24 hours (earlier, was 36
hours for Alvarado)
– Sensitivity and specificity were >95%
– 60% use of CT, 18% use of CT + US
Ultrasonography
• Annals of Emergency Medicine, Clinical
Policy on Suspected Appendicitis, 2010
– Level B recommendation, use US “to confirm
acute appy but not to definitively exclude it.”
– Use CT “to confirm or exclude acute appy.”
– Level C, “consider using US as the initial
imaging modality. In cases in which the dx
remains uncertain, CT may be performed.”
Ultrasound
• What is a (+) US?
– Diagnostic criteria for appendicitis are an
appendix greater than 6 mm in diameter
– A noncompressible appendix
– Appendiceal tenderness.
• Limitations
– the appendix may be obscured (by bowel gas
or overlying fat) or difficult to find (eg,
retrocecal position)
Ultrasound
• The 7 studies that evaluate the diagnostic
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accuracy of ultrasound in pediatric appendicitis
support the idea that ultrasound is better at
positively identifying appendicitis than excluding
it
Although 3 of the 7 studies report negative
likelihood ratios for US less than 0.1, 5 of these
7 studies report positive likelihood ratios greater
than 10
Ultrasound
• Sensitivity likely in the 88% range
• Specificity in the 95% range
• Operator specific, accuracy improves with
the volume of studies performed
– High volume centers report less “appendix not
visualized”
Combining US and CT
• Harvard warning
– Karakas, et al, 1999. 633 children.
Perforation rate increased “substantially”
among pts who underwent both US and CT
– This is presumed to be due to a delay in
reaching the OR
– In rural Canada, prolonged transfer to a
pediatric surgeon correlated with perforatoin
Combining US and CT
• Future Research: A study evaluating a
Bayesian approach using ultrasound to
diagnose appendicitis in children would be
very helpful. For example, such a study
would identify the probabilities of
appendicitis in children with low,
moderate, and high pre-test clinical
suspicion.
Combining US and CT
• From Schneider, et al (Annals, 2007) “One
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editorial argues that both ultrasonography and
CT can have a role in diagnosis
According to the editorial, the main goal of
imaging should be rational use of imaging
resources and radiation dose reduction.
Perhaps the ideal scoring system could clearly
stratify patients into those who can go directly to
the operating room, those who should have
radiologic imaging, and those who can be
observed.”
Banner CPG (Finally!)
• Assign a modified Alvarado Score
– RLQ Pain (1 point)
– Anorexia (1 point)
– N/V (1 point)
– RLQ TTP (1 point)
– Rebound in RLQ (2 points)
– Fever >37.5C (1 point)
– WBC >10K (2 points)
Banner CPG
• Stratify risk according to score
– 0-3 low risk, send home with good follow-up
– 4-6 intermediate risk, will require imaging
– 7-9, high risk, send to Peds ER for surgical
consultation, may be able to avoid imaging
and speed time to OR, reduce risk of rupture
• Avoid the radiation and delay of “confirming the
diagnosis”
Banner CPG
• Those children requiring imaging will undergo
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US if their body habitus is amenable
This will require transferring children to a Peds
ED where experienced US techs and radiologists
are present
Those children undergoing CT can stay put
– This includes slim children whose pain has been >48
hours in duration
Limited CT Appendicitis Protocol
• T-Bird developed a “Limited” CT for
pediatric r/o appy
• From L1 to symphysis pubis (pelvis only)
• IV contrast only
• Significantly reduced radiation and time to
study completion
• Indicated for pain <48 hours
CT with PO and IV contrast
• Because of the increased rate of
perforation and abscess formation, as well
obstruction, children with pain >48 hours
will still undergo CT Abd/Pelvis with both
PO and IV contrast
Banner CPG
• Children with (+) CT may be transferred to the
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inpatient pediatric service to await
appendectomy
Children with a negative CT may be sent home
or observed if needed
Children with a negative US should proceed to
CT if there is high suspicion
Children with a (+) CT after US will go to OR
Cerner Clinical Decision Support
• Cerner will apply these rules “behind the
scenes” so that you can answer questions
after the labs are back and appropriate
orders will be suggested
• This will allow Cerner to track the Alvarado
score and the resulting physician order
• Finally, Outcomes Research!!
Cerner Clinical Decision Support
• Do I need to use Decision Support?
– Yes!
• Simplifies use of the new guideline
• Allows quality control and tracking of
expense
• You must hit “done” to record the score
but can delete orders from scratchpad
What will need to be tracked?
• Use of CT (desired direction=less)
• Rate of perforation (less)
• Rate of negative appendectomy (stable)
• Number of patients transferred and
attendant cost (qualitative)
• Number of children undergoing dual
imaging (false negative rate of US)
• Total cost of imaging (qualitative)
Expected Outcomes
• Less use of CT in low pretest probability
children
• Increased use of US in mid-pretest
probability children
• Decreased use of any imaging in high
pretest children, faster time to OR
• Faster transfer to peds surgeon (less time
at referral center), faster arrival in OR
Expected Outcomes
• More children completing their evaluation
in the Peds ED (being sent without
imaging)
• More chlidren moving to the Peds ED
– Some children will have negative US and will
be sent back home, but may have been
spared CT or unnecessary direct admit