CME - Appendicitis - Dx and Presurgical Management.

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.

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[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