Article: Diagnostic Performance of Wells Score Combined with Point-of-care lung and Venous Ultrasound in Suspected Pulmonary Embolism. Acad Emerg Med. 2017 Mar;24(3):270-280.

Objective: To see if Ultrasound-enhanced Wells Score (USWs) performed better than the Wells Score (Ws) when diagnosing pulmonary embolism (PE) in the emergency department (ED). Specifically, the ultrasound was used to assess the lungs for an alternative diagnosis and assess the veins for deep venous thrombosis.

Study Design: Observational cohort multicenter diagnostic accuracy study

Inclusion Criteria: Patients greater than 18 years old with symptoms suggestive of PE (dyspnea, chest pain, syncope, palpitations)

Exclusion: If ultrasound was not performed within 3 hours of when patient presented to ED.

Results: A total of 446 patients were enrolled in the study. They found that the USWs > 4 was more sensitive (69.6% vs 57.6%) and specific (88.2% vs 68.2%) than just the Ws > 4 for confirming PE. However, the ultrasound-modified Wells score still relied on the use of D-Dimer studies when ruling out PE. The failure rate between the the USWs and the Ws did not show a statistical significance difference, though the efficacy for USWs was higher than the Ws (32.3% vs 27.2%). Secondary findings included lower use of CT pulmonary angiogram when D-Dimer was included with USWs was used as compared to Ws (50.5% decrease vs 27.2%).

Limitations: 1. The study did not include an echo to further help with the diagnosis of PE.

2. There were varying levels of competency with the ultrasound machine.

3. The rate of PE was found to be 28% in the study population, which the authors suggest is high.

4. The study focused on comparing USWs to Ws. Other findings, such as utilizing D-Dimer with the USWs, were not specifically studied and final conclusions cannot be drawn.

Study Conclusion: There was a statistically significant difference between utilizing USWs and Ws with a score > 4 that showed improved sensitivity, sensitivity and efficacy when utilizing USWs. There was no statistically significant difference in failure rate between the two diagnostic tools.

Final Thoughts: Though the study showed improvement with the USWs compared to the Ws with a score > 4, it still relied on the use of D-Dimer to effectively ruling out PE and there was not a difference in the failure rate between the tools. More studies are needed to evaluate if USWs can completely take the place of Ws, especially if a D-Dimer is still needed to rule out PE. Two cons in using USWs instead of Ws is the potential to increase time that patients spend in the ED while waiting to have the study done as well as the additional cost for the ultrasound study. Additionally, if ultrasounds are being utilized to evaluate for PE, then the cardiac exam should be included as well to evaluate for right heart strain, an indication for severe PE.

Post by Vittoria Boni, MS4