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Brachial plexus block at the level of the axilla is typically chosen
for anesthesia of the distal upper limb. Axillary block is a basic regional
anesthesia technique and perhaps the most common approach to brachial plexus
blockade. Low risk of serious complications, superficial location, and good analgesia of the upper
arm muscles make this block suitable for ambulatory procedures of longer
duration that require a tourniquet.
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The surgical technique of this block was first described by
Hall1 in New York (Roosevelt Hospital) in 1884, and the
percutaneous technique was described by Hirschel2 in 1911.
While dissecting the axilla in a child in 1958, Burnham,3
recognized that filling the neurovascular sheath with local anesthetic could
simplify the axillary block. He also described the characteristic fascial
“click” felt on penetration by the needle. In 1961 while using the formula
for a cylinder volume, De Jong4 calculated that in an
average adult, 42 mL of local anesthetic (LA) was necessary to fill the
fascial compartment to the level of the cords and block all terminal nerves
to the arm. A year later, Eriksson and Skarby,5 in an
effort to promote the proximal spread of LA, advocated wrapping a rubber
tourniquet around the arm, distal to the needle. In 1979, Winnie and
coworkers6 found the tourniquet ineffective and painful
and recommended firm distal digital pressure on the neurovascular sheath
instead. In addition, they also recommended arm adduction after LA
injection, thinking that the head of the abducted humerus compressed the
neurovascular sheath. Both maneuvers were later proved to be clinically
ineffective.7–9 Thompson and Rorie,10
in 1983, studied brachial plexus using computed tomograms and suggested that
the median, ulnar, and radial nerves lie in separate fascial compartments
within the neurovascular sheath; this finding provided a rational
explanation for incomplete blocks. However, anatomic studies by Lassale and
Ang11 in 1984 and Vester-Andersen and
coworkers12 in 1986 did not confirm the existence of a
true neurovascular sheath. The interfascial space they found contained the
median and the ulnar nerves, infrequently the musculocutaneous, and
occasionally the radial nerves. Moreover, the space was suggested to
communicate proximally only with the medial cord of the plexus. In 1987
Partridge and coworkers13 described the interneural septa,
which were easily broken by injection of dyed latex. In 2002 Klaastad and
coworkers14 were the first to investigate the spread of
the LA through the axillary catheter in studies using magnetic resonance
imaging (MRI) scanning. They found that in most patients the spread of LA
was uneven and the clinical effect inadequate.
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Until the 1960s, the prevalent block techniques were double or multiple
axillary injections. After the concept of the neurovascular sheath had been
established by De Jong4 in 1961, the single-injection
technique, being the simplest, became standard. However, Vester-Andersen and
coworkers15,16 demonstrated in 1983 and 1984, that despite
high volumes of LA, analgesia was often inconsistent (“patchy”). In ...