Perform screening and anesthetic selection if not already completed.
What is the injury location?
Table 2 lists suggested equipment for ultrasound guidance. Use an ultrasound machine with a high-frequency (10-15 MHz) linear array transducer. These transducers often come in several different sized footprints. A wider footprint (eg, 3.8 or 5 cm) can be helpful and allow visualization of more surrounding structures and a longer needle path; however, for certain anatomical locations (eg, the ankle) and smaller patients, a smaller footprint transducer (eg, 2.5-cm linear array) is easier to use. A photo demonstrating supplies and assembly of a 2-operator injection set-up is provided in Figure 1.