Invasive procedures are frequently performed in the ED. Traditionally, these 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. In recent years, the use of point-of-care 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, know 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.
Ultrasound is a highly operator-dependent technology and the success of an ultrasound-guided or -assisted procedure will depend on the skill of the physician performing the procedure. The amount of training required to successfully perform these procedures has not been well defined in the literature. In the 2008 American College of Emergency Physicians (ACEP) Emergency Ultrasound Guidelines, performance of a minimum of ten ultrasound-guided procedures or completion of a module on ultrasound-guided procedures with simulation on a high-quality ultrasound phantom is recommended for hospital privileging.1 However, it is acknowledged that the training process for emergency ultrasound should move beyond strict numbers and should include experiential and competency components.
Dynamic Guidance and Static Guidance
Procedures can be performed using either ultrasound guidance (dynamic) or ultrasound assistance (static). Ultrasound guidance entails performing the procedure while imaging the target and needle in real-time during the procedure. Ultrasound assistance entails performing the procedure 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. Procedures involving small target structures or procedures requiring precise placement of the needle are best performed under ultrasound guidance. Procedures such as paracentesis, thoracentesis, and abscess drainage are frequently performed using ultrasound assistance since the fluid collections tend to be larger, and once anatomy and pathology are marked out, it is typically safe to proceed blindly.
Ultrasound-guided procedures can be performed using either a one-operator or two-operator technique. In a one-operator technique, the operator controls the transducer while simultaneously performing the procedure. In a two-operator technique, a second operator (assistant) controls the transducer while the first operator simultaneously performs the procedure. For those just learning to perform ultrasound-guided procedures, it is recommended that the one-operator technique be emphasized. In a study involving ultrasound ...