CHAPTER 18 Vertical infraclavicular block
Sonoanatomy
The ultrasound-guided infraclavicular technique is performed over the pectoral region. In view of the increased depth at which the brachial plexus is found at this level with respect to other techniques, the ultrasound transducer should be of lower frequency (4–7 MHz). Scanning is performed laterally in proximity to the coracoid process (Fig 18.4). The ultrasound transducer (curvilinear, held in a sagittal orientation) is placed near the lower edge of the clavicle, and a transverse view (parasagittal plane) of the axillary artery and vein is obtained (Fig 18.5). A good alternative is to use a small curved transducer for infraclavicular scanning since it provides a wider field of view and more space for needle insertion. However, phased array or linear transducers can also be used. Care should be used not to apply too much downward pressure on the transducer, which may occlude the axillary vein. The Doppler options facilitate identification of the vascular structures.