CT for Suspected Pulmonary Embolism

CT for Suspected Pulmonary Embolism

Evidence supports that CT scans to evaluate for blood clots in the lung, a condition called pulmonary embolism (PE), are increasingly over-utilized and leading to many of these studies being negative when conducted. There are many evidence-based tools and risk calculators to guide medical decision-making to help stratify patients and better tailor an approach to evaluating for this diagnosis prior to obtaining a CT. It is important that this test be used for only patients at elevated risk for the disease because these types of CT scans expose patients to ionizing radiation and use of a dye in the veins during the test that can cause kidney injury. This approach has been endorsed as a Choosing Wisely recommendation by the American College of Emergency Physicians. Within MEDIC, we measure clinical performance using the percentage of CT scans ordered for suspected PE that are positive for PE, also called diagnostic yield.

MEDIC Suspected PE Toolkit

Key References

  • Christopher Study Investigators. Effectiveness of Managing Suspected Pulmonary Embolism Using an Algorithm Combining Clinical Probability, D-Dimer Testing, and Computed Tomography. JAMA. 2006;295(2):172.
  • Kline JA, Courtney DM, Kabrhel C, et al. Prospective multicenter evaluation of the pulmonary embolism rule-out criteria. Journal of Thrombosis and Haemostasis. 2008;6(5):772-780. doi:10.1111/j.1538-7836.2008.02944.x
  • Kline JA, Kabrhel C. Emergency Evaluation for Pulmonary Embolism, Part 2: Diagnostic Approach. The Journal of Emergency Medicine. 2015;49(1):104-117.
  • Kline JA, Mitchell AM, Kabrhel C, et al. Clinical Criteria to Prevent Unnecessary Diagnostic Testing in Emergency Department Patients with Suspected Pulmonary Embolism. Journal of Thrombosis and Haemostasis. 2004;2:1247-1255.
  • Righini M, Van Es J, Den Exter P, et al. Age-Adjusted D-Dimer Cutoff Levels to Rule Out Pulmonary Embolism. JAMA. 2014;311(11):1117.
  • Schouten H, Geersing G, Koek H, et al. Diagnostic accuracy of conventional or age adjusted D-dimer cut-off values in older patients with suspected venous thromboembolism: systematic review and meta-analysis. BMJ. 2013;346(may03 1).
  • Singh B, Parsaik AK, Agarwal D, et al. Diagnostic Accuracy of Pulmonary Embolism Rule-Out Criteria: A Systematic Review and Meta-analysis. Annals of Emergency Medicine. 2012;59:517-520.
  • Wells P, Anderson D, Rodger M, et al. Derivation of a Simple Clinical Model to Categorize Patients Probability of Pulmonary Embolism: Increasing the Models Utility with the SimpliRED D-dimer. Thrombosis and Haemostasis. 2000;83(03):416-420.