Ultrasound Assessment of Pulmonary Embolism in Patients Receiving Computerized Tomography Pulmonary Angiography.
Chest. 2013 Oct 31;
Authors: Koenig S, Chandra S, Alaverdian A, Dibello C, Mayo PH, Narasimhan M
ABSTRACT BACKGROUND: CT pulmonary angiogram (CTPA) is considered the gold standard for the diagnosis of pulmonary embolism (PE) and is frequently performed in patients with cardiopulmonary complaints. However, indiscriminate use of CTPA results in significant exposure to ionizing radiation and contrast. We studied the accuracy of a bedside ultrasound protocol to predict need for CTPA.
METHODS: Observational study performed by pulmonary/critical care physicians trained in critical care ultrasonography. Screening ultrasound was performed when a CTPA was ordered to rule out PE. The ultrasound exam consisted of a limited echocardiogram, thoracic ultrasonography, and lower extremity deep venous compression study. We predicted that CTPA was not needed if either DVT was found, or clear evidence of an alternative diagnosis was established. CTPA parenchymal and pleural findings were compared, and when available, formal DVT and echocardiography results, with our screening ultrasound.
RESULTS: Ninety six subjects had a CTPA of which 12/96 (12.5%) were positive for PE. All 96 subjects had an ultrasound study of which 2 (2.1%) were positive for LEDVT and 54 (56.2%) had an alternative diagnosis suggested by ultrasonography, such as alveolar consolidation consistent with pneumonia or pulmonary edema, which correlated with CTPA findings. In no patient did the CTPA add additional diagnosis over screening ultrasound study.
CONCLUSIONS: We conclude that ultrasonography examination indicated that CTPA was not needed in 56/96 (58.3%) of patients. A screening, point of care ultrasonography protocol may predict the need for CTPA. Furthermore, an alternative diagnosis can be established that correlates with CTPA. This study needs further verification, but it offers a possible approach to reduce the cost and radiation exposure that is associated with CTPA.
PMID: 24178672 [PubMed - as supplied by publisher]