Cost-effectiveness of computed tomography and ultrasound in the diagnosis of appendicitis

Álvaro Sanabria, Javier Romero, Miguel Angarita, Juan Carlos Varón, .

Keywords: appendicitis/diagnosis, cost-benefit analysis, tomography, ultrasonography, physical examination, decision support techniques

Abstract

Introduction. Diagnosis of acute appendicitis is difficult in nearly 30% of patients with pain in low right quadrant. Diagnostic imaging may provide a means of a more accurate diagnosis.
Objective. The cost-effectiveness of diagnostic image tests was calculated for comparison with routine physical examination in patients with abdominal pain suspected to be appendicitis.
Materials and methods. A cost-effectiveness protocol was designed, using a decision analysis model. The standard case  was a patient with abdominal pain in right lower quadrant and suspicion of appendicitis. Three independent diagnostic alternatives were selected-ultrasonography, abdominal tomography and physical exam  in hospital with the subject under observation less than six hours. Operative characteristics, study design and costs of interventions and outcomes were assessed. The main outcome consisted of a confirmed diagnosis of appendicitis. The point of view taken was that of health maintenance organizations. Direct and indirect medical costs were measured. Time horizon used was three months. A one way sensitivity analysis was made.
Results. For a prepaid system, the most cost-effective strategy was abdominal tomography, with a cost-effectiveness ratio of US$965/diagnosed patient. For public system, the most cost-effective strategy was abdominal tomography, with a cost-effectiveness ratio of US$492/diagnosed patient.
Conclusions. Imaging diagnostic methods, in cases of abdominal pain suspected to be appendicitis, are more cost-effective than physical exam to make accurate diagnostic decisions. Tomography offers the best cost-effectiveness in prepaid system and in public health system.

Downloads

Download data is not yet available.
  • Álvaro Sanabria Department of Surgery, Universidad de la Sabana, Chía, Cundinamarca, Colombia. Fundación Abood Shaio, Bogotá D.C., Colombia
  • Javier Romero Department of Radiology, Fundación Santa Fe de Bogotá, Bogotá D.C., Colombia
  • Miguel Angarita Department of Radiology, Fundación Santa Fe de Bogotá, Bogotá D.C., Colombia
  • Juan Carlos Varón Department of Surgery, Universidad El Bosque, Bogotá D.C., Colombia

References

1. Horattas MC, Guyton DP, Wu D. A reappraisal of appendicitis in the elderly. Am J Surg. 1990;160:291-3.
2. Agafonoff S, Hawke I, Khadra M, Munnings V, Notaras L, Wadhwa S, et al. The influence of age and gender on normal appendicectomy rates. Aust N Z J Surg. 1987;57:843-6.
3. Korner H, Sondenaa K, Soreide JA, Andersen E, Nysted A, Lende TH, et al. Incidence of acute nonperforated and perforated appendicitis: age-specific and sex-specific analysis. World J Surg. 1997;21:313-7.
4. Andersson RE, Hugander A, Thulin AJ. Diagnostic accuracy and perforation rate in appendicitis: association with age and sex of the patient and with appendicectomy rate. Eur J Surg. 1992;158:37-41.
5. Kirby CP, Sparnon AL. Active observation of children with possible appendicitis does not increase morbidity. ANZ J Surg. 2001;71:412-3.
6. Bachoo P, Mahomed AA, Ninan GK, Youngson GG. Acute appendicitis: the continuing role for active observation. Pediatr Surg Int. 2001;17:125-8.
7. Andersson RE, Hugander A, Ravn H, Offenbartl K, Ghazi SH, Nystrom PO, et al. Repeated clinical and laboratory examinations in patients with an equivocal diagnosis of appendicitis. World J Surg. 2000;24:479-85.
8. Dolgin SE, Beck AR, Tartter PI. The risk of perforation when children with possible appendicitis are observed in the hospital. Surg Gynecol Obstet. 1992;175:320-4.
9. Axelrod DA, Sonnad SS, Hirschl RB. An economic evaluation of sonographic examination of children with suspected appendicitis. J Pediatr Surg. 2000;35: 1236-41.
10. Fujii Y, Hata J, Futagami K, Hamada T, Mitsuoka H, Teramen K, et al. Ultrasonography improves diagnostic accuracy of acute appendicitis and provides cost savings to hospitals in Japan. J Ultrasound Med. 2000;19:409-14.
11. Chen SC, Chen KM, Wang SM, Chang KJ. Abdominal sonography screening of clinically diagnosed or suspected appendicitis before surgery. World J Surg. 1998;22:449-52.
12. Franke C, Bohner H, Yang Q, Ohmann C, Roher HD. Ultrasonography for diagnosis of acute appendicitis: results of a prospective multicenter trial. Acute Abdominal Pain Study Group. World J Surg. 1999;23: 141-6.
13. Baldisserotto M, Cavazzola S, Cavazzola LT, Lopes MH, Mottin CC. Acute edematous stump appendicitis diagnosed preoperatively on sonography. AJR Am J Roentgenol. 2000;175:503-4.
14. Soda K, Nemoto K, Yoshizawa S, Hibiki T, Shizuya K, Konishi F. Detection of pinpoint tenderness on the appendix under ultrasonography is useful to confirm acute appendicitis. Arch Surg. 2001;136:1136-40.
15. Stroman DL, Bayouth CV, Kuhn JA, Westmoreland M, Jones RC, Fisher TL, et al. The role of computed tomography in the diagnosis of acute appendicitis. Am J Surg. 1999;178:485-9.
16. Gwynn LK. The diagnosis of acute appendicitis: clinical assessment versus computed tomography evaluation. J Emerg Med. 2001;21:119-23.
17. Wise SW, Labuski MR, Kasales CJ, Blebea JS, Meilstrup JW, Holley GP, et al. Comparative assessment of CT and sonographic techniques for appendiceal imaging. AJR Am J Roentgenol. 2001;176:933-41.
18. Horton MD, Counter SF, Florence MG, Hart MJ. A prospective trial of computed tomography and ultrasonography for diagnosing appendicitis in the atypical patient. Am J Surg. 2000;179:379-81.
19. Lane MJ, Liu DM, Huynh MD, Jeffrey RB Jr, Mindelzun RE, Katz DS. Suspected acute appendicitis: nonenhanced helical CT in 300 consecutive patients. Radiology. 1999;213:341-6.
20. Sivit CJ, Applegate KE, Berlin SC, Myers MT, Stallion A, Dudgeon DL, et al. Evaluation of suspected appendicitis in children and young adults: helical CT. Radiology. 2000;216:430-3.
21. Weltman DI, Yu J, Krumenacker J Jr, Huang S, Moh P. Diagnosis of acute appendicitis: comparison of 5- and 10-mm CT sections in the same patient. Radiology. 2000;216:172-7.
22. Wijetunga R, Tan BS, Rouse JC, Bigg-Wither GW, Doust BD. Diagnostic accuracy of focused appendiceal CT in clinically equivocal cases of acute appendicitis. Radiology. 2001;221:747-53.
23. Fefferman NR, Roche KJ, Pinkney LP, Ambrosino MM, Genieser NB. Suspected appendicitis in children: focused CT technique for evaluation. Radiology. 2001;220:691-5.
24. Jacobs JE, Birnbaum BA, Macari M, Megibow AJ, Israel G, Maki DD, et al. Acute appendicitis: comparison of helical CT diagnosis focused technique with oral contrast material versus nonfocused technique with oral and intravenous contrast material. Radiology. 2001;220:683-90.
25. Pena BM, Taylor GA, Fishman SJ, Mandl KD. Costs and effectiveness of ultrasonography and limited computed tomography for diagnosing appendicitis in children. Pediatrics. 2000;106:672-6.
26. Pena BM, Taylor GA, Lund DP, Mandl KD. Effect of computed tomography on patient management and costs in children with suspected appendicitis. Pediatrics. 1999;104:440-6.
27. Bryan S, Brown J. Extrapolation of cost-effectiveness information to local settings. J Health Serv Res Policy. 1998;3:108-12.
28. Drummond MF, Bloom BS, Carrin G, Hillman AL, Hutchings HC, Knill-Jones RP, et al. Issues in the cross-national assessment of health technology. Int J Technol Assess Health Care. 1992;8:671-82.
29. Doria AS, Moineddin R, Kellenberger CJ, Epelman M, Beyene J, Schuh S, et al. US or CT for diagnosis of appendicitis in children and adults? A meta-analysis. Radiology. 2006;241:83-94.
30. Weston AR, Jackson TJ, Blamey S. Diagnosis of appendicitis in adults by ultrasonography or computed tomography: a systematic review and meta-analysis. Int J Technol Assess Health Care. 2005;21:368-79.
31. Terasawa T, Blackmore CC, Bent S, Kohlwes RJ. Systematic review: computed tomography and ultrasonography to detect acute appendicitis in adults and adolescents. Ann Intern Med. 2004;141:537-46.
32. Rao PM, Feltmate CM, Rhea JT, Schulick AH, Novelline RA. Helical computed tomography in differentiating appendicitis and acute gynecologic conditions. Obstet Gynecol. 1999;93:417-21.
33. Walker S, Haun W, Clark J, McMillin K, Zeren F, Gilliland T. The value of limited computed tomography with rectal contrast in the diagnosis of acute appendicitis. Am J Surg. 2000;180:450-4.
34. Peck J, Peck A, Peck C, Peck J. The clinical role of noncontrast helical computed tomography in the diagnosis of acute appendicitis. Am J Surg 2000;180:133-6.
35. Nakhgevany KB, Clarke LE. Acute appendicitis in women of childbearing age. Arch Surg. 1986;121:1053-5.
36. Jess P, Bjerregaard B, Brynitz S, Holst-Christensen J, Kalaja E, Lund-Kristensen J. Acute appendicitis. Prospective trial concerning diagnostic accuracy and complications. Am J Surg. 1981;141:232-4.
37. Gronroos JM, Gronroos P. A fertile-aged woman with right lower abdominal pain but unelevated leukocyte count and C-reactive protein. Acute appendicitis is very unlikely. Langenbecks Arch Surg. 1999;384:437-40.
38. Rothrock SG, Green SM, Dobson M, Colucciello SA, Simmons CM. Misdiagnosis of appendicitis in nonpregnant women of childbearing age. J Emerg Med. 1995;13:1-8. 
How to Cite
1.
Sanabria Álvaro, Romero J, Angarita M, Varón JC. Cost-effectiveness of computed tomography and ultrasound in the diagnosis of appendicitis. biomedica [Internet]. 2008 Mar. 1 [cited 2024 May 15];28(1):139-47. Available from: https://revistabiomedica.org/index.php/biomedica/article/view/116
Published
2008-03-01
Section
Original articles

Altmetric

Article metrics
Abstract views
Galley vies
PDF Views
HTML views
Other views
QR Code