Overuse of Computed Tomography Pulmonary Angiography in the Evaluation of Patients with Suspected Pulmonary Embolism in the Emergency Department

Abstract

Background Clinical decision rules have been developed and validated for the evaluation of patients presenting with suspected pulmonary embolism (PE) to the emergency department (ED). Objectives To assess the percentage of computed tomographic pulmonary angiography (CT-PA) which could have been avoided by use of the Wells score coupled with D-dimer testing (Wells/D-dimer) or Pulmonary Embolism Rule-Out Criteria (PERC) in ED patients with suspected PE. Methods The authors conducted a prospective cohort study of adult ED patients undergoing CT-PA for suspected PE. Wells score and PERC were calculated. A research blood sample was obtained for D-dimer testing for subjects who did not undergo testing as part of their ED evaluation. The primary outcome was PE by CT-PA or 90-day follow-up. Secondary outcomes were ED length of stay (LOS) and CT-PA time as defined by time from order to initial radiologist interpretation. Results Of 152 suspected PE subjects available for analysis (mean age 46.3±15.6 years, 74% female, 59% black or African American, 11.8% diagnosed with PE), 14 (9.2%) met PERC, none of whom were diagnosed with PE. A low-risk Wells score (≤4) was assigned to 110 (72%) subjects, of whom only 38 (35%) underwent clinical D-dimer testing (elevated in 33/38). Of the 72 subjects with low-risk Wells scores who did not have D-dimers performed in the ED, archived research samples were negative in 16 (22%). All 21 subjects with low-risk Wells scores and negative D-dimers were PE-negative. CT-PA time (median 160 minutes) accounted for more than half of total ED LOS (median 295 minutes). Conclusions In total, 9.2% and 13.8% of CT-PA could have been avoided by use of PERC and Wells/D-dimer, respectively.

Age‐adjusted D‐dimer cutoff for the diagnosis of pulmonary embolism: A cost‐effectiveness analysis

“…Utilities and disutilities of relevant health states were abstracted from a study reporting standard‐gamble estimates by 216 VTE patients . The differential loss of time between the two strategies, from the differential use of CTPA and consequently longer time for patients, was included as a full disutility and estimated at 160 minutes from a US prospective cohort …”

Yield of CT Pulmonary Angiography in the Emergency Department When Providers Override Evidence-based Clinical Decision Support

“…Although the Wells criteria, a validated, evidence-based decision tool designed to help providers identify patients who require CT pulmonary angiography to exclude PE, have existed for more than a decade (10), their use in clinical practice remains sparse (11)(12)(13).…”

Predictive value of symptoms, signs and biomarkers on computed tomography pulmonary angiogram results

“…The drawbacks of CTPA, however, include the risks of contrast nephropathy and allergy, radiation exposure and the potential for incidental findings, which lack clinical implication but require further investigation. In addition, unnecessary ordering of CTPA is costly to healthcare systems …”

“…In addition, unnecessary ordering of CTPA is costly to healthcare systems. 13 Current evidence suggests that sensitive D-dimer testing can be combined with clinical findings and decision rules to exclude PE safely, thus circumventing some avoidable costs and unnecessary imaging. 14,15 Despite this, there is an increasing use of CTPA in the assessment of patients with cardiorespiratory symptoms.…”