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Ultrasound is routinely incorporated into the work-up of patients with a variety of trauma, critical care, or emergency surgical disorders.1,2,3,4,5,6 Despite advances in other superior imaging modalities such as multidetector-row computed tomography (MDCT), the ability to acquire real-time data with ultrasound allows the surgeon to make critical decisions expeditiously with minimal risk of complications. Surgeons are personally capable of obtaining good quality images and interpreting the examination independently.7,8,9 Presently, medical students, surgical residents and fellows have become familiar with the management of trauma patients and those with emergency general surgery problems using ultrasound as they have multiple opportunities to learn the technique of bedside ultrasound examination.10 Similarly, the management of critically ill patients including resuscitation, hemodynamic monitoring, and procedural guidance has drastically changed in the past few decades as the ultrasound examination is more commonly performed.11,12,13,14,15 These critical care ultrasound studies can be completed at the bedside and avoid transporting patients from the intensive care unit (ICU). In addition to basic techniques to identify free fluid in the abdominal cavity, surgical intensivists have successfully applied the advanced echocardiographic examination to guide the resuscitation of critically ill patients.16,17,18 This chapter reviews the indications, techniques, and currently available data for ultrasound examinations in trauma, emergency general surgery, and critical care patients.
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Ultrasonography is operator-dependent. Therefore, an understanding of select principles of ultrasound physics is necessary so that images may be acquired rapidly and interpreted correctly. Knowledge of these basic principles enables the acute care surgeon to select the appropriate transducer, optimize resolution of the image, and recognize artifacts. Some basic terms and principles of physics relative to ultrasound imaging in the acute setting are defined in Tables 16-1, 16-2, 16-3.
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