KMCTH

1. World J Gastroenterol 2015 February 21; 21(7): 2131-2139
Sang Chul Lee, Byung-JoChoi, Say-June Kim, Department of
Surgery, Daejeon St. Mary’s Hospital, the Catholic University of
Korea, Daejeon 420-743, South Korea
Geon Park, Department of Radiology, Daejeon St. Mary’s
Hospital, the Catholic University of Korea, Daejeon 420-743,
South Korea
Determination of surgical priorities in appendicitis
based on
the probability of undetected appendiceal
Perforation

2. Introduction
 Appendicitis: most frequently encountered surgical emergency
worldwide
 early appendectomy therapeutic gold standard to avoid
complications.
 A report indicated that although 41% of patients visited the
emergency room between 11 PM and 8 AM, only 6% of
operations were performed during that period, showing
inconsistent durations between the patient visit and operative
timing

3.  Besides the hospital visiting hour, appendectomy timing is
inconsistently determined by various factors.
 Therefore, guidelines for the optimal timing of appendicectomy are
necessary.

4.  The incidence of appendiceal perforation has been reported to range
from 17% to 32%.
 Appendiceal perforation increases morbidity in terms of extended
treatment with antibiotics, greater risk of complications, and longer
hospital stays.
 cases of microperforated or nonperforated appendicitis should be
treated promptly according to the surgical priority, which should be
determined based on the risk of gross perforation.

5.  Abdominal computed tomography (CT) scan is widely used for
predicting both the presence of appendicitis and its perforation.
 CT was found to have a low sensitivity (62%) in predicting appendiceal
perforation
 considerable number of patients with perforated appendicitis could be
incorrectly diagnosed radiologically as nonperforated.
 these patients require prompt operation because they are at the risk
of progression to gross contamination.

6.  In this study, of the patients with radiologically
nonperforated appendicitis, they selected patients with
actual perforation evidenced by the operative and
pathologic features.
 They intended to determine risk factors that could be
useful in predicting actual perforation based on the clinical
criteria in patients whose CT scans suggested
nonperforated appendicitis.

7.  AIM:
 To identify risk factors of actual appendiceal perforation
when computed tomography (CT) scans suggest
nonperforated appendicitis and accordingly determine
surgical priority.

8. Materials and method
 Study location-
Daejeon St. Mary’s Hospital, the Catholic University of
Korea,
 Study Period-January 2006 and December 2013.
 Study design- Retrospective case control study
 Sample size- 1362

9.  Inclusion Criteria
 Patients who underwent appendectomy with the impression of
nonperforated appendicitis based on preoperative CT scan
 Exclusion Criteria
• Patients who underwent more than simple appendectomy
• Patient who underwent appendectomy 3 day after admission
• Patient who did not receive preoperative CT scan

11. Statistical analysis
 Numeric data were presented as mean and standard deviation or as median
and range
 Continuous variables were analyzed using the independent t-test
 proportions were compared using Pearson’s χ 2 test or Fisher’s exact test
 For variables with a non-normal distribution, Wilcoxon rank sum tests were
utilized to examine differences in central tendency
 Binary logistic regression was used to assess the risk of in-hospital perforation
while controlling for other independent variables.
 Statistical analysis was performed using SPSS ver. 15.0 Statistical significance
was accepted for P values < 0.05.

13.  Patients with actual appendiceal perforation were
 older (> 35 years of age, 80% vs 53.1%, P < 0.001)
 had a body temperature > 37.7 ºC (28.9% vs 15.8%, P <
0.05),
 neutrophil fraction > 65% (88.9% vs 79.7%, P < 0.05),
 and appendiceal diameter > 8 mm (97.8% vs 88.7%, P < 0.05).
 Both groups were similar with respect to sex, body mass
index, comorbidity, and out-of-hospital delay.

14. Identification of factors related with actual
appendiceal
perforation
 Multivariate analysis was performed using
preoperative variables
 They identified independent factors related with
actual appendiceal perforation
 including body temperature (< 37.6 ℃ vs ≥ 37.6 ℃),
 out-of-hospital delay (< 72 h vs ≥ 72 h),
 age (< 35 years vs ≥ 35 years),
 Appendiceal diameter (< 8 mm vs ≥ 8 mm).

15.  Using these 4 risk factors related with actual appendiceal perforation,
 we further stratified patients into 3 groups:
 low-risk (risk factor: 0-1),
 intermediate-risk (risk factors
 and high-risk group (risk factors: 3-4)

16. Clinical outcomes of patients with actual perforation
who were diagnosed as having nonperforation on CT
scan

17.  postoperative complications were classified according to
Clavien’s proposal
 The actual perforation group had higher incidence of grade
2 (14.4% vs 8.2%, P = 0.051), grade 3 (7.8% vs 1.2%, P <
0.001),
and total number of complications (22.2% vs 9.9%, P <
0.05).
 The difference in the complication rates was more marked
for grade 3

19.  All grade 3 complications in both groups resulted in
reoperation,possibly owing to our propensity to adopt
a more rapid and definitive management;
 the actual perforation group also had a significantly
higher reoperation rate (P < 0.001).
 Regardless of perforation, intra-abdominal abscess (n
= 14) was the leading cause of reoperation, and
intestinal obstruction (n = 6) was the second.

20. Discussion
 the diagnostic yield of appendiceal perforation by
abdominal CT is considerably low
 7.3% of patients with nonperforated appendicitis on CT
images were found to have an actual perforation
 Independent factors that could be useful in discriminating
between actual nonperforation and actual perforation in
patients diagnosed with nonperforation radiologically were
identified

21.  Time-to-incision did not affect the perforation, which
suggests a low possibility of in-hospital perforation
 four independent factors that can be useful to
determine the presence of appendiceal Perforation
were identified
 body temperature ≥ 37.6 ℃,
 out-of hospital symptom duration ≥ 72 h
 age ≥ 35 years,
 appendiceal diameter on CT scan ≥ 8 mm

22.  patients with acute appendicitis  the risk of developing
advanced pathology and complications increased with time to
treatment, favoring prompt appendectomy
 Kearney et al reported that the stage of appendicitis was
affected by out-of-hospital delay, but not by in-hospital delay
 These differences may be attributed to variations in study
design, patient characteristics, and inclusion/exclusion criteria
 further clarification of the optimal operation timing is required

23.  This study do not fully support either timing; rather prompt
appendectomy for the selected patients who have high-risk factors for
actual perforation
 In this , patients with actual perforation showed
 longer operation time,
 delayed initiation of postoperative diet
 longer and higher doses of postoperative analgesics
 higher incidences of postoperative complications
 longer hospital stay.
 Therefore, performing appendectomy before its perforation is crucial
in the treatment of appendicitis

24. Conclusion
 actual appendiceal perforation occurred in 7.3% of the
patients whose CT scans suggested nonperforated
appendicitis.
 Perforation group-require prompt operation because they
are at the risk of progression to gross contamination
 Prediction of perforated appendicitis could be done
 body temperature ≥ 37.6 ℃,
 out-of-hospital symptom duration ≥ 72 h,
 age ≥ 35 years
 appendiceal diameter on CT scan ≥ 8 mm.

31. (A) Are the results of the study
valid?
 Did the study address a clearly focused issue?
 The population studied
 The risk factors studied
 Whether the study tried to detect a beneficial or harmful
effect?
 Did the authors use an appropriateto answer their
question?
 Is a case control study an appropriate way of Answering
the question under the circumstances?
(Is the outcome rare or harmful)
 Did it address the study question?

32. Is it worth continuing?
 Were the cases recruited in an acceptable
way?
(selection bias)
 Are the cases defined precisely?
 Were the cases representative of a defined
population? (geographically and/or
temporally?)
 Is the time frame of the study relevant to
disease/exposure?
 Was there a sufficient number of cases
selected?

33.  Were the controls selected in an acceptable way?
 Were the controls representative of defined
population (geographically and/or temporally)
 Are they matched, population based or
randomly
selected?
 Was there a sufficient number of controls
selected

34.  Can the results be applied to the local
population?
 The subjects covered in the study could be
sufficiently different from your population to cause
concern
 Your local setting is likely to differ much from that of
the study
 Can you quantify the local benefits and harms?