Ultrasound Blocks for the Anterior Abdominal Wall

32 | Ultrasound Blocks for the Anterior Abdominal Wall
interpreted by the clinician at the bedside. Ultrasounds have
been used to guide needle insertion, and a number of approaches
to nerves and plexuses (groups of nerves) have been reported.
A clear advantage of the technique is that ultrasound produces
”living pictures” or “real-time” images. The identification of
neuronal and adjacent anatomical structures (blood vessels,
peritoneum, bone, organs) along with the needle is another
advantage.
Figure 2.4 – Needle parallel to short and long axis of the transducer:
out-of-plane and in-plane approaches.
Ultrasounds use has been rated as one of the safest practices
for patients. The prevention of intravascular injection during
regional anesthesia blocks is best accomplished with a
combination of ultrasound technique and epinephrine test
dosing (Neal 2010).
Moreover, anatomical variability may be responsible for block
failures, and ultrasound technology enabling direct visualization
may overcome this problem. Many studies show that complex
nerve plexus block as well as single nerve block techniques can
be successfully performed with lower volumes of local
anesthetics. Sonographic visualization allows for the