Page 3 of 3Pearls & Pitfalls for The eFAST Exam
1. Use a 3-5 MHz curvilinear or phased array transducer to obtain images of the abdomen during the eFAST exam.
2. Remember that the eFAST is a focused, limited, bedside ultrasound application used to answer a select set of questions.
3. The eFAST can help practitioners diagnose a pneumothorax, determine if the patient has pleural fluid present above the diaphragm, visualize a pericardial effusion and detect intra-abdominal free fluid in the right upper quadrant, left upper quadrant, and pelvis.
4. Although its ability to diagnose solid organ injuries has not been well studied yet, it is important to know what solid organ injuries may look like on bedside ultrasound in case you come across them during your scan.
5. Train your eyes to know what a normal liver and spleen look like. Lacerations will often appear as irregularly shaped anechoic stripes within the organ parenchyma.
6. To determine if the anechoic area is a vessel or a laceration, apply color Doppler over the area of interest. Note that very large and actively bleeding lacerations may demonstrate a small amount of color flow, but the appearance of the color flow will be markedly different than that seen over normal adjacent veins and arteries.
7. A positive FAST provides very useful information that can help with management and imaging decisions when resources are limited or when a patient is hemodynamically unstable.
8. The FAST has a high specificity for detecting hemoperitoneum (89%-99%) but also carries a low sensitivity (73%-97%). If your patient has a normal FAST, remember the limitations of the scan, and consider obtaining a CT scan if there is a moderate to high suspicion for intra-abdominal, retroperitoneal or pelvic trauma.
9. Remember that Practice Makes Proficient. With bedside ultrasound there is no substitute for experience.
Teresa Wu is the EM Ultrasound Director and Co-Director for Simulation Based Training for the Maricopa Emergency Medicine Program in Phoenix, Arizona.
Brady Pregerson manages a free online EM Ultrasound Image Library and is the editor of the Emergency Medicine Pocketbook series. For more information visit ERPocketBooks.com