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Traumatic injury is the leading cause of death among individuals younger than 45 years old. Eighty percent of traumatic injury is blunt with the majority of deaths secondary to hypovolemic shock. Intraperitoneal bleeds occur in 12 percent of blunt trauma; therefore, it is essential to identify trauma quickly. The optimal test should be rapid, accurate, and non-invasive. The implementation of point of care ultrasound has significantly impacted the evaluation and treatment of patients. This activity describes the indications for FAST and highlights the role of the interprofessional team in the rapid evaluation of the trauma patient to help improve patient outcomes. Objectives: Explain the limitations of a Focused Assessment with Sonography for Trauma (FAST) exam. Summarize the indications for a Focused Assessment with Sonography for Trauma (FAST) exam. Explain how to perform a Focused Assessment with Sonography for Trauma (FAST) exam. Explain the importance of collaboration and communication among the interprofessional team to ensure appropriate selection of candidates for Focused Assessment with Sonography for Trauma (FAST) to enhance the management of trauma patients and improve outcomes. Access free multiple choice questions on this topic.

Traumatic injury is the leading cause of death among individuals younger than 45 years old [1]. Eighty percent of traumatic injury is blunt with the majority of deaths secondary to hypovolemic shock [2]. In fact, intraperitoneal bleeds occur in 12% of blunt trauma [3]; therefore, it is essential to identify trauma quickly. The optimal test should be rapid, accurate, and non-invasive. Historically, providers performed diagnostic peritoneal lavage (DPL) to detect hemoperitoneum. While extremely sensitive (96% to 99%) and specific (98%), DPL is an invasive procedure with a complication rate of 1% [4],[5], [6]. CT remains the gold standard for diagnosing intra-abdominal injuries detecting as little as 100 cc of intraperitoneal fluid.  However, time delays and transportation out of the emergency department confound the evaluation of hemodynamically unstable patients. The implementation of point of care ultrasound has significantly impacted the evaluation and treatment of patients [7]. Ultrasound has considerable advantages, including its bedside availability, ease of use, and reproducibility. Furthermore, it is non-invasive, employs no radiation or contrast agents, and is inexpensive. The use of ultrasound to detect intraperitoneal fluid was first described in Europe during the 1970s. However, widespread adoption in the United States did not occur until the 1990s. The Focused Assessment with Sonography in Trauma (FAST) is an ultrasound protocol developed to assess for hemoperitoneum and hemopericardium. Numerous studies have demonstrated sensitivities between 85% to 96% and specificities exceeding 98% [8]. In the subset of hypotensive trauma patients, the sensitivity of the FAST exam approaches 100%. Experienced providers perform the FAST exam in less than 5 minutes [9], and its use decreases time to surgical intervention, patient length of stay, and rates of CT and DPL[1]. Presently, more than 96% of level 1 trauma centers incorporate FAST into their trauma algorithms as does Advanced Trauma Life Support (ATLS) [10]. Recently, many institutions have introduced the Extended FAST (eFAST) protocol into their trauma algorithms. The eFAST examines each hemithorax for the presence of hemothoraces and pneumothoraces.

There are no known complications from the eFAST exam. However, ultrasound has several limitations. It is only 85% sensitive requiring the presence of more than 150 cc to 200 cc of intra-peritoneal fluid to detect [19]. Serial FAST exams can help prevent false-negative studies [7]. Other false negatives include patients with delayed presentations whose hemorrhage has clotted causing a mixed echogenicity rather than the anechoic or black appearance of fresh blood or fluid. False positives include ascites, peritoneal dialysate, ruptured ovarian cysts, and ruptured ectopic pregnancies. Additionally, ultrasound cannot distinguish between blood and urine in severe pelvic trauma and cannot evaluate retroperitoneal hemorrhages. Most importantly, the point of care ultrasound image acquisition and interpretation is limited by the provider’s experience; the patient’s body habitus; and the presence of bowel gas, pneumoperitoneum, or pneumomediastinum. Serial eFAST exams and advanced imaging are warranted in these situations based on the patient’s hemodynamic status.

The management of trauma patients is usually with an interprofessional team including trauma nurses. While FAST is useful in trauma patients, it has limitations. Clinicians should be aware that the point of care ultrasound image acquisition and interpretation is limited by the provider’s experience; the patient’s body habitus; and the presence of bowel gas, pneumoperitoneum, or pneumomediastinum. Serial eFAST exams and advanced imaging are warranted in these situations based on the patient’s hemodynamic status. A radiologist should be consulted if one is not able to interpret the images; unfortunately this may not always be possible in the middle of the night.[20][21]