Invasive procedures are frequently performed in the emergency department. Traditionally, these invasive procedures have been performed by emergency physicians who relied on physical assessment for making the correct diagnosis and surface landmarks for determining the correct approach for an invasive procedure. In recent years, the use of bedside ultrasound has been incorporated into the practice of many emergency physicians to guide or assist in the performance of a variety of invasive procedures.
The use of ultrasound guidance (dynamic guidance) or ultrasound assistance (static guidance) to perform certain procedures can decrease complications when utilized correctly. Before performing any procedure under ultrasound guidance, it is imperative that clinicians have a thorough understanding of sonographic anatomy, the basic principles of ultrasound, and have practical training with phantoms or models to develop the hand–eye coordination required. Lack of familiarity with ultrasound and the orientation of the image on the screen can lead to complications even in the hands of a physician skilled at performing the procedure in a “blind” fashion.
Procedures can be performed using either ultrasound guidance (dynamic) or ultrasound assistance (static). In real-time ultrasound guidance, the procedure is performed while imaging the target during the procedure. In ultrasound assistance, the procedure is performed in the traditional fashion after the anatomy and any pathology has been mapped by ultrasound and the entry point marked.
The decision to perform a procedure under ultrasound guidance or ultrasound assistance is based on the procedure itself. Some procedures are simply inherently more dangerous when not performed under real-time guidance. In the case of others, there is only slightly more danger when real-time visualization is not utilized after an initial ultrasound assessment. For these procedures, it is often a matter physician experience and preference that may be the deciding factor. Procedures such as paracentesis, thoracentesis, and abscess drainage are frequently performed using ultrasound assistance since the fluid collections tend to be static, and once anatomy and pathology are marked out, it is typically safe to proceed blindly. Vascular access, paracentesis, and foreign body removal are examples of applications typically performed under ultrasound guidance.
Ultrasound-guided procedures can be performed with the physician holding the transducer with one hand and using the free hand to perform the procedure. The free hand may be holding a needle, forceps, or be manipulating tissue itself. In the two-operator approach, one person holds the ultrasound transducer and another person performs the actual procedure. Physicians in many settings may not have the option of having a colleague assist them because of staffing levels or how busy a setting they work in. For others, it is a matter of personal preference. Having an additional person holding the transducer means coordinating actions with another person. Similar to ultrasound-guided vascular access, it may simply be easier for one person to do both in a dynamic setting such as when a needle or forceps are moving ...