Update on appendicitis: Diagnosis and presurgical
management - Janet H Friday
- Diagnostic tests - overview (what is
being done now?)
- Hx, PE, WBC, CRP levels
- MANTRELS score
- Movement of pain to RIF
- Anorexia
- Nausea
- Tenderness in RIF
- Rebound tenderness
- Elevated temperature
- Leukocytosis
- Shift of WBC to left
- Diagnostic imaging
- US,
- IV contrast CT
- Issues with the current diagnostic
methods
- MANTREL score has low sensitivity
(76-90%) and specificity (50-81%)
- Abdominal CT has the best individual
test, but it may be being carried out too rapidly.
- Diagnosing Appendicitis with Ultrasound
- 14 published studies cited including
over 10000 children who underwent US scans for evaluation of possible
appendicitis
- Sensitivity varied from 50-100%
- Specificity ranges from 88-99%
- Which means negative US scan does not
exclude appendicitis unless normal appendix correctly visualized.
- Imaging protocol
- Every patient undergo US before CT
scan
- If US inconclusive / negative, CT
performed
- This has resulted in 22% of patient
CT avoidance.
- Some people may be better off doing
US
- Adolescent female - blood supply to
ovaries can be obvserved.
- Thin people - easier to visualize
internal organs
- Children - CT contraindicated due to
radiation
- Diagnosing Appendicitis with CT
- Dx with CT scan has sensitivity of
97%, specificity of 94%[i]
- Contrast-enhanced CT seem to have a
higher reliability than non contrast CT-enhanced CT.
- The issue with CT
- Since the publication of reports of
diagnostic accuracy of CT, the CT scans in children has increased
seven-folds in US[ii]
- In one year, 753 patients assessed
for appendicitis (2001), where 172 were <18. In this group, 138 (80%)
went thru CT scanning for suspected appendicitis, and 62(45%) were
negative.
- Unnecessarily CT scans are being
performed.
- New clinical decision rule
- Kharbanda et al[iii]
- Nausea (2 pts)
- Hx of focal right lower quadrant pain
(2pts)
- Migration of pain (1pt)
- Difficulty walking (1pt)
- Rebound tenderness (2pts)
- Absolute Neutrophil Count more than
6.75x103 (6pts)
- Score up to 5 had a sensitivity (of no
appendicitis) of 96%, a negative predictive value of 96%.
- A recursive-partitioning model was
created, and the following variables were found to be important
- ANC > 6.75x103
- Nausea (emesis and anorexia were
surrogate variables)
- Maximal tenderness in RLQ.
- When all 3 were absent, the rule had
sensitivity of 100% for identifying low-risk patients.
- Presurgical management - analgesics
- According to Kim et al[iv] and Kokki and
associates[v]
- Analgesic use in children will not
affect the diagnostic accuracy of appendicitis.
- Analgesia may be given before
surgeon’s examination.
- Use of analgesia may be acceptable
especially when waiting for the consultant to arrive.
- Presurgical management - Antibiotics
- 45 published studies of 9576 adults
and children with appendicitis who were randomized to be given either
antibiotics or placebo before, during, or after appendectomy
- Use
of antibiotics were superior to placebo for preventing wound infection
and intra-abdominal abscess, regardless of whether perforation has
occurred.
- Recent recommendation
- Meropenem
- Imipenem
- Ampicillin, gentamycin, clindamycin
(generic)
Take home message - MANTRELS
scoring may be outdated - we need to look at ANC values, consider US before CT,
can use analgesics, good to use antibiotics presurgically.
[i] Garcia Pena et al Ultrasonography and limited computed tomography
in the diagnosis and management of appendicitis in children. JAMA 1999;
15:1041-1046
[ii] National Caner Institute. Radiation and Pediatric computed
tomography: a guide for health care providers. Summer newsletter; 2002 1-4
[iii] Kharbanda AB, Taylor GA, et al A clinical decision rule to identify
children at low risk for appendicitis. Pediatrics 2005; 116:709-716
[iv] Kim MK, Strait RT, Sato TT, et. Al. A randomized clinical trial of
analgesia in children with acute abdominal pain. Acad Emerg Med 2002; 9:281-287
[v] Kokki H, Lintula H, Vanamo K, et al. Oxycodone vs placembo in
children with undifferentiated abdominal pain; a randomized, double-blind
clinical trial of the effect of analgesia on diagnostic accuracy. Arch Pediatr
Adolesc Med 2005; 159:320-325
