The application of a clinical risk stratification score may reduce unnecessary investigations for pulmonary embolism in pregnancy

Abstract

Objective: To examine the use of the modified Wells score in pregnancy as a risk stratification tool in the diagnosis of pulmonary embolism (PE). Methods: All pregnant or post-partum patients who were referred for CT Pulmonary Angiography (CTPA) to evaluate suspected PE over a 5-year period were included in the study. Patient records were used to apply the modified Wells score (MWS) and analyze their risk of PE. Results: A total of 125 women were referred for CTPA over 5 years. A MWS of 6 or greater (“High Risk”) was 100% sensitive and 90% specific with a positive predictive value of 36% for PE on CTPA. No patients with a low MWS (less than 6) had a PE, giving a negative predictive value of 100%. p ≤ 0.001. D-dimers, chest X-ray, blood gases and EKG were significantly less effective than the MWS in aiding the diagnosis of PE. Conclusion: Current methods employed for the diagnosis of PE are inadequate. Risk stratification using the MWS may allow safe exclusion of PE before resorting to CTPA. To the best of our knowledge this is the first study to have used the MWS in a pregnant patient group.

Keywords::

• CT pulmonary angiography
• modified Wells score
• pregnancy
• pulmonary embolism
• venous thromboembolism

Acknowledgements

Clare O’Connor is the primary author of this article, writing all drafts up to the final manuscript. John Moriarty and Jennifer Walsh contributed extensive intellectual and editorial advice and ideas. William Boyd, John Murray and Sam Coulter-Smith also contributed intellectual mentorship in the final preparation of the manuscript.

We are grateful to the department of Radiology in the Mater Misericordiae University hospital for providing a list of all the referrals for CT-PA over a five-year period. We are also very grateful to the Rotunda Hospital for facilitating the study.

Declaration of interest: The authors report no conflict of interest.