Optimizing the safety and practice of ultrasound-guided regional anesthesia: the role of echogenic technology.

aSchool of Medicine and Pharmacology, The University of Western Australia bSir Charles Gairdner Hospital, Perth, Western Australia, Australia.
Current opinion in anaesthesiology 07/2012; 25(5):603-9. DOI:10.1097/ACO.0b013e328356b835
Source: PubMed

ABSTRACT Significant improvements have been made in the quality of ultrasound imaging, and it is now much easier to see nerves. However, the key to safe ultrasound-guided regional anesthesia is to be able to direct the needle to the target. This relies on good needle visibility. We review the recent advances that have been made in this crucial area.
Echogenic needles can improve shaft and tip visibility independent of experience level, compensate for suboptimal scanning technique, allow steeper insertion angles, reduce technical difficulty, and increase both confidence and satisfaction by anesthesiologists. An echogenic needle encourages holding the probe in one place on the patient, only advancing the needle when it can be seen, hence reducing the likelihood of quality-compromising behaviors. The poor visibility of nonechogenic needles when inserted at steeper angles commonly causes the observer to underestimate the insertion depth of the needle. Significant differences in echogenicity are found when comparing the currently available needles.
Good echogenic needles should increase safety, efficacy, and simplicity, and hopefully further drive the adoption of ultrasound-guided techniques, to the benefit of our patients.

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