Pre-Operative Imaging can Reduce Negative Appendectomy Rate in Acute Appendicitis

Jeremy Chan, Ka Siu Fan, Tsz Lun Allenis Mak, Sook Yin Loh, Stephanie Wai Yee Ng, Ravi Adapala, Jeremy Chan, Ka Siu Fan, Tsz Lun Allenis Mak, Sook Yin Loh, Stephanie Wai Yee Ng, Ravi Adapala

Abstract

Introduction: Acute appendicitis is a common surgical emergency, with a prevalence of 112 per 100,000 people per year in Europe. Negative appendicectomy is defined as a pathologically normal appendix removed from patient suspected with appendicitis. Negative appendectomy rate (NAR) has been reported to be around 15-25%. We aimed to evaluate our unit's negative appendectomy rate and the effect of pre-operative imaging on NAR.

Method: A retrospective study including all patients who underwent both open and laparoscopic emergency appendicectomy in a single district general hospital from 2017-2018. Clinical information including cost was calculated based on the 2017/18 national tariff payment system. Patients under 18 years old were excluded from this study.

Results: Two hundred thirty-two patients were included in this study, of which 69 (29.74%) had a pre-operative CT scan. The mean length of stay was 2.57 days. The sensitivity, specificity, positive predictive value and negative predictive value for CT were 77.8%, 100%, 87.5% and 100%. The negative appendicectomy rate with and without pre-operative CT scan were 7.25% and 22.09% respectively. Based on the 2017/18 national tariff payment system, a CT abdomen and pelvis with contrast and emergency appendicectomy with CC score of 0 cost 92 and 2370 pounds respectively. The total cost of patients who underwent appendicectomy without imaging was £ 322,320. If all patients undergo pre-operative CT, with a reduction of 15% in negative appendicectomy rate, the overall total cost would significantly lower to £ 36,212.

Conclusion: Our study demonstrated that the negative appendicectomy rate could be improved by preoperative imaging. The study also showed that implementation of preoperative imaging for suspected appendicitis cases could save costs, allowing better allocation of resources.

Keywords: Acute appendicitis; Negative appendectomy rate; Routine Imaging.

Conflict of interest statement

Provenance: externally peer reviewed

Copyright © 2020 Ulster Medical Society.

References

    1. Ferris M, Quan S, Kaplan BS, Molodecky N, Ball CG, Chernoff GW, et al. The global incidence of appendicitis: A systematic review of population-based studies. Ann Surg. 2017;266(2):237–41.
    1. Drake FT, Mottey NE, Farrokhi ET, Florence MG, Johnson MG, Mock C, et al. Time to appendectomy and risk of perforation in acute appendicitis. JAMA Surg. 2014;149(8):837–44.
    1. Baird DLH, Simillis C, Kontovounisios C, Rasheed S, Tekkis PP. Acute appendicitis. BMJ. 2017;357:j1703.
    1. Humes DJ, Simpson J. Acute appendicitis. BMJ. 2006;333(7567):530–4.
    1. Raja AS, Wright C, Sodickson AD, Zane RD, Schiff GD, Hanson R, et al. Negative appendectomy rate in the era of CT: An 18-year perspective. Radiology. 2010;256(2):460–5.
    1. Stephenson J, Al-Nowfal A, Khatiwada AS, Lim Z, Norwood M, Verma R. Can imaging have a beneficial effect on reducing negative appendicectomy rates. Clinical Radiology. 2018;73(Suppl 1):e21.
    1. Boonstra PA, van Veen RN, Stockmann HB. Less negative appendectomies due to imaging in patients with suspected appendicitis. Surg Endosc. 2015;29(8):2365–70.
    1. D'Souza N, Marsden M, Bottomley S, Nagarajah N, Scutt F, Toh S. Cost-effectiveness of routine imaging of suspected appendicitis. Ann R Coll Surg Engl. 2018;100(1):47–51.
    1. Lahaye MJ, Lambregts DM, Mutsaers E, Essers BA, Breukink S, Cappendijk VC, et al. Mandatory imaging cuts costs and reduces the rate of unnecessary surgeries in the diagnostic work-up of patients suspected of having appendicitis. Eur Radiol. 2015;25(5):1464–70.
    1. Lehtimaki TT, Valtonen H, Miettinen P, Juvonen P Paajanen H, Vanninen R. A randomised clinical trial of routine versus selective CT imaging in acute abdomen: Impact of patient age on treatment costs and hospital resource use. Eur J Radiol. 2017;87:1–7.
    1. Association of Surgeons of Great Britain and Ireland . Royal College of surgeons Advancing Surgical Standards. Commissioning Guide: Emergency general surgery (acute abdominal pain). London: Association of Surgeons of Great Britain and Ireland; 2014.
    1. Mostbeck G, Adam E, Nielsen M, Claudon M, Clevert D, Nicolau C, et al. How to diagnose acute appendicitis: ultrasound first. Insights Imaging. 2016;7(2):255–63.
    1. Needham PJ, Laughlan KA, Botterill ID, Ambrose NS. Laparoscopic appendicectomy: calculating the cost. Ann R Coll Surg Engl. 2009;91(7):606–8.
    1. Minutolo V, Licciardello A, Di Stefano B, Arena M, Arena G, Antonacci V. Outcomes and cost analysis of laparoscopic versus open appendectomy for treatment of acute appendicitis: 4-years experience in a district hospital. BMC Surg. 2014;14:14.
    1. Costa-Navarro D, Jimenez-Fuertes M, Illan-Riquelme A. Laparoscopic appendectomy: quality care and cost-effectiveness for today's economy. World J Emerg Surg. 2013;8(1):45.
    1. National Surgical Research Collaborative Multicentre observational study of performance variation in provision and outcome of emergency appendicectomy. Br J Surg. 2013;100(9):1240–52.
    1. Lee M, Paavana T, Mazari F, Wilson TR. The morbidity of negative appendicectomy. Ann R Coll Surg Engl. 2014;96(7):517–20.
    1. Keyzer C, Zalcman M, De Maertelaer V, Coppens E, Bali MA, Gevenois PA, et al. Comparison of US and unenhanced multi-detector row CT in patients suspected of having acute appendicitis. Radiology. 2005;236(2):527–34.
    1. van Randen A, Bipat S, Zwinderman AH, Ubbink DT, Stoker J, Boermeester MA. Acute appendicitis: meta-analysis of diagnostic performance of CT and graded compression US related to prevalence of disease. Radiology. 2008;249(1):97–106.
    1. 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(1):83–94.
    1. Alfraih Y, Postuma R, Keijzer R. How do you diagnose appendicitis? An international evaluation of methods. Int J Surg. 2014;12(5):67–70.
    1. van Rossem CC, Bolmers MD, Schreinemacher MH, van Geloven AA, Bemelman WA. Snapshot Appendicitis Collaborative Study Group Prospective nationwide outcome audit of surgery for suspected acute appendicitis. Br J Surg. 2016;103(1):144–51.
    1. Drake FT, Florence MG, Johnson MG, Jurkovich GJ, Kwon S, Schmidt Z, et al. Progress in the diagnosis of appendicitis: report from Washington State's Surgical Care and Outcomes Assessment Program. Ann Surg. 2012;256(4):586–94.
    1. Karakas SP, Guelfguat M, Leonidas JC, Springer S, Singh SP. Acute appendicitis in children: comparison of clinical diagnosis with ultrasound CT imaging. Pediatr Radiol. 2000;30(2):94–8.
    1. Yu SH, Kim CB, Park JW, Kim MS, Radosevich DM. Ultrasonography in the diagnosis of appendicitis: evaluation by meta-analysis. Korean J Radiol. 2005;6(4):267–77.
    1. Heverhagen JT, Pfestroff K, HeverhagenAE, Klose KJ, Kessler K, Sitter H. Diagnostic accuracy of magnetic resonance imaging: A prospective evaluation of patients with suspected appendicitis (diamond) J Magn Reson Imaging. 2012;35(3):617–23.
    1. Kim K, Lee CC, Song K, Kim W, Suh G, Singer AJ. The impact of helical computed tomography on the negative appendectomy rate: a multi-center comparison. J Emerg Med. 2008;34(1):3–6.
    1. Bhangu A. Safety of short, in-hospital delays before surgery for acute appendicitis: multicentre cohort study, systematic review, and meta-analysis. Ann Surg. 2014;259(5):894–903.
    1. United Kingdom National Surgical Research Collaborative, Bhangu A Safety of short, in-hospital delays before surgery for acute appendicitis: multicentre cohort study, systematic review, and meta-analysis. Ann Surg. 2014;259(5):894–903.
    1. Brenner DJ, Hall EJ. Computed tomography - an increasing source of radiation exposure. N Engl J Med. 2007;357(22):2277–84.
    1. Smith-Bindman R, Wang Y, Chu P, Chung R, Einstein AJ, Balcombe J, et al. International variation in radiation dose for computed tomography examinations: prospective cohort study. BMJ. 2019;364:k4931.
    1. Keyzer C, Tack D, de Maertelaer V, Bohy P, Gevenois PA, Van Gansbeke D. Acute appendicitis: Comparison of low-dose and standard-dose unenhanced multi-detector row CT. Radiology. 2004;232(1):164–172. doi: .
    1. Seo H, Lee KH, Kim HJ, Kim K, Kang SB, Kim SY, et al. Diagnosis of acute appendicitis with sliding slab ray-sum interpretation of low-dose unenhanced CT and standard-dose i.v. contrast-enhanced CT scans. AJR Am J Roentgenol. 2009;193(1):96–105.
    1. Kelly ME, Heeney A, Redmond CE, Costelloe J, Nason GJ, Ryan J, et al. Incidental findings detected on emergency abdominal CT scans: A 1-year review. Abdom Imaging. 2015;40(6):1853–7.

Source: PubMed

Sponsors and Collaborators

Medical Conditions

Drug Interventions

3
Subscribe