CT of Children with Suspected Appendicitis
CT of Children with Suspected Appendicitis
Abstract & Commentary
Synopsis: Children who are being evaluated for possible appendicitis are often admitted for observation despite the availability of accurate diagnostic studies. A proposed strategy of obtaining a computed tomography scan while the patient is in the emergency room is shown to reduce costs and improve outcomes of children with appendicitis.
Source: Garcia-Pena BM, et al. Effect of computed tomography on patient management and costs in children with suspected appendicitis. Pediatrics 1999;104(3):440-446.
Acute appendicitis is a common emergency condition in children, and prompt diagnosis and surgery decreases the morbidity and mortality considerably. The diagnosis of appendicitis in children is a challenge, with up to 20% of children initially incorrectly diagnosed. Using sensitivity analysis, this study examined the cost-effectiveness of abdominal computed tomography (CT) scan in the emergency room patient for the diagnosis of acute appendicitis. Three strategies were applied to the retrospective cohort of patients admitted for observation. Outcomes and costs under the modeled strategies were compared with those under current practice. The strategies were: 1) CT scans on all patients and discharge of those with normal findings; 2) To obtain CT scans and admit all patients; and 3) CT scan on all patients admitted for observation with a peripheral white blood cell count greater than 10,000/mm3 and admit all.
The results of 609 patients were reviewed. Forty-seven percent (287/609) were sent directly for appendectomy, and 14 with perforation and known abscess diagnosed were treated with antibiotics IV and drainage. The remaining 308 children comprised the study cohort having suggestive, but not definite, appendicitis. The age range of this group was 0.5-25 years with mean age 10.9 years. This group was evaluated using the strategies listed before. Of this group, 36% (112/308) underwent appendectomy, with 23% showing normal appendix. Forty-two (14%) had perforated appendicitis at surgery or by pathology. Three patients discharged with normal CT scans were readmitted with appendicitis and represent false-negative CT study. Seventy-five patients of the total 609 children admitted for possible appendicitis had an abdominal CT scan on admission. The sensitivity and specificity of the CT was 97% (95% CI, 0.92-1.00 and 0.89-1.00).
Conclusions of the study are that CT scan in the emergency room with any of the three strategies noted resulted in improved accuracy and cost-effectiveness in the diagnosis of appendicitis compared with their current practice, which was to obtain a sonogram, CT, or no imaging, admit the patient for observation, and obtain a sonogram or CT while inpatients.
Comment By Beverly P. Wood, MD, MS
Justification of the use of CT in the emergency room patient with suspected appendicitis is indicated as savings in time and overall cost while performing more sensitive diagnostic imaging. The major savings are in the avoidance of missed appendicitis or delay in diagnosis with resultant perforation. In overall financial expenditure, it may be in avoiding hospitalization for observation of equivocal cases. In this study, there were two documented cases of "missed" appendicitis by CT, WBC, and admission, and three "missed" cases by CT and discharge home. The advantage to the ER use of CT is avoidance of unnecessary hospitalizations.
Presumably, CT is more sensitive and specific than abdominal ultrasound (US); however, the study may be reflecting the "interpreter comfort and confidence" in the study or the availability of CT (or US) on an emergency basis. Timely and repeated clinical examination of patients by an experienced examiner is another factor that needs to be placed in the overall equation. Clearly, acquisition of large numbers of CT scans is not cost-effective and we are primarily dependent on the good clinical judgment of evaluators.
A comparison of the effectiveness and sensitivity of CT and US in the same cohort of patients would be a most interesting follow-up to this study.
Subscribe Now for Access
You have reached your article limit for the month. We hope you found our articles both enjoyable and insightful. For information on new subscriptions, product trials, alternative billing arrangements or group and site discounts please call 800-688-2421. We look forward to having you as a long-term member of the Relias Media community.