Connect
MJA
MJA

Changing trends in venous thromboembolism-related imaging in Western Australian teaching hospitals, 2002–2010

Tatiana Segard and William B G Macdonald
Med J Aust 2013; 198 (2): 100-103. || doi: 10.5694/mja12.11002

Summary

Objective: To determine trends in referral for venous thromboembolism (VTE) imaging in Western Australian teaching hospitals.

Design and setting: Retrospective audit of the WA picture archiving and communication system, PathWest Laboratory Medicine records, the hospital morbidity database at the four adult teaching hospitals in Perth, WA, and the WA death registry.

Patients: All patients referred for VTE-related imaging, and all hospital separations for pulmonary embolism (PE) during 2002–2010.

Main outcome measures: Number of referrals for computed tomography pulmonary angiography (CTPA), ventilation–perfusion lung scintigraphy, leg ultrasound and plasma D-dimer assay; hospital separations for PE and deaths from PE.

Results: Referrals for VTE-related imaging increased by 34%, while PE-related imaging increased by 65% during the study period, owing entirely to referrals for CTPA, which increased by more than 500%. The number of hospital separations for PE increased by 45% over the same period and the prevalence of PE among referred patients fell from 22.1% in 2002 to 19.5% in 2010. There was no fall in the death rate from PE in WA during the study period (P = 0.19). The number of D-dimer tests performed in the same hospitals increased by 42% over the study period.

Conclusions: The increased number of referrals for PE-related imaging resulted in more diagnoses but no reduction in deaths from PE in WA. Widespread D-dimer testing did not reduce referrals for imaging and is likely to have resulted in increased referrals. Increased imaging leads to overdiagnosis of clinically insignificant PE, and alternative strategies are required to reduce PE death rates.

  • Tatiana Segard1
  • William B G Macdonald2

  • 1 Nuclear Medicine, Sir Charles Gairdner Hospital, Perth, WA.
  • 2 Imaging West, Department of Health, Western Australia, Perth, WA.


Acknowledgements: 

We thank Andrew Campbell for his assistance with statistical analysis, and the data custodians of the WA Department of Health and the WA Registry of Births, Deaths and Marriages for provision of the data.

Competing interests:

William Macdonald is a member of the editorial board of Diagnostic Imaging Pathways and provides advice regarding nuclear medicine imaging. He receives no payment for this work.

  • 1. Roy PM, Meyer G, Vielle B, et al. Appropriateness of diagnostic management and outcomes of suspected pulmonary embolism. Ann Intern Med 2006; 144: 157-164.
  • 2. Bairstow PJ, Persaud J, Mendelson R, Nguyen L. Reducing inappropriate diagnostic practice through education and decision support. Int J Qual Health Care 2010; 22: 194-200.
  • 3. Roy PM, Durieux P, Gillaizeau F, et al. A computerized handheld decision-support system to improve pulmonary embolism diagnosis: a randomized trial. Ann Intern Med 2009; 151: 677-686.
  • 4. Wells PS, Anderson DR, Rodger M, et al. Excluding pulmonary embolism at the bedside without diagnostic imaging: management of patients with suspected pulmonary embolism presenting to the emergency department by using a simple clinical model and d-dimer. Ann Intern Med 2001; 135: 98-107.
  • 5. Righini M, Perrier A, De Moerloose P, Bounameaux H. D-Dimer for venous thromboembolism diagnosis: 20 years later. J Thromb Haemost 2008; 6: 1059-1071.
  • 6. Government of Western Australia, Department of Health. Diagnostic Imaging Pathways: a clinical decision support tool and educational resource for diagnostic imaging. http://www.imaging pathways.health.wa.gov.au (accessed Sep 2012).
  • 7. Australian Bureau of Statistics. Australian demographic statistics. Table 4. Estimated resident population, states and territories (number). (ABS Cat. No. 3101.0.) http://www.ausstats.abs.gov.au/ausstats/ABS@ Archive.nsf/0/3042DF15A46B22D6CA25796 8000D0C57/$File/310104.xls#A2060847T (accessed Feb 2012).
  • 8. Le Gal G, Bounameaux H. Diagnosing pulmonary embolism: running after the decreasing prevalence of cases among suspected patients. J Thromb Haemost 2004; 2: 1244-1246.
  • 9. Wiener RS, Schwartz LM, Woloshin S. Time trends in pulmonary embolism in the United States: evidence of overdiagnosis. Arch Intern Med 2011; 171: 831-837.
  • 10. Bounameaux H, Slosman D, de Moerloose P, Reber G. Diagnostic value of plasma D-dimer in suspected pulmonary embolism. Lancet 1988; 2: 628-629.
  • 11. Kohn MA, Kwan E, Gupta M, Tabas JA. Prevalence of acute myocardial infarction and other serious diagnoses in patients presenting to an urban emergency department with chest pain. J Emerg Med 2005; 29: 383-390.
  • 12. Ho WK, Hankey GJ, Eikelboom JW. The incidence of venous thromboembolism: a prospective, community-based study in Perth, Western Australia. Med J Aust 2008; 189: 144-147. <MJA full text>
  • 13. Douma RA, Kessels JB, Buller HR, Gerdes VE. Knowledge of the D-dimer test result influences clinical probability assessment of pulmonary embolism. Thromb Res 2010; 126: e271-e275.
  • 14. Goldstein NM, Kollef MH, Ward S, Gage BF. The impact of the introduction of a rapid D-dimer assay on the diagnostic evaluation of suspected pulmonary embolism. Arch Intern Med 2001; 161: 567-571.
  • 15. Smith C, Mensah A, Mal S, Worster A. Is pretest probability assessment on emergency department patients with suspected venous thromboembolism documented before SimpliRED D-dimer testing? CJEM 2008; 10: 519-523.
  • 16. Jones P, Elangbam B, Williams NR. Inappropriate use and interpretation of D-dimer testing in the emergency department: an unexpected adverse effect of meeting the “4-h target”. Emerg Med J 2010; 27: 43-47.
  • 17. The PIOPED Investigators. Value of the ventilation/perfusion scan in acute pulmonary embolism. Results of the prospective investigation of pulmonary embolism diagnosis (PIOPED). JAMA 1990; 263: 2753-2759.
  • 18. Larson DB, Johnson LW, Schnell BM, et al. National trends in CT use in the emergency department: 1995-2007. Radiology 2011; 258: 164-173.
  • 19. Mettler FA Jr, Bhargavan M, Faulkner K, et al. Radiologic and nuclear medicine studies in the United States and worldwide: frequency, radiation dose, and comparison with other radiation sources — 1950-2007. Radiology 2009; 253: 520-531.
  • 20. Burge AJ, Freeman KD, Klapper PJ, Haramati LB. Increased diagnosis of pulmonary embolism without a corresponding decline in mortality during the CT era. Clin Radiol 2008; 63: 381-386.
  • 21. Glassroth J. Imaging of pulmonary embolism: too much of a good thing? JAMA 2007; 298: 2788-2789.
  • 22. Suh JM, Cronan JJ, Healey TT. Dots are not clots: the over-diagnosis and over-treatment of PE. Emerg Radiol 2010; 17: 347-352.

Author

remove_circle_outline Delete Author
add_circle_outline Add Author

Comment
Do you have any competing interests to declare? *

I/we agree to assign copyright to the Medical Journal of Australia and agree to the Conditions of publication *
I/we agree to the Terms of use of the Medical Journal of Australia *
Email me when people comment on this article

Responses are now closed for this article.