S. Kapral et al., ULTRASOUND IMAGING FOR STELLATE GANGLION BLOCK - DIRECT VISUALIZATIONOF PUNCTURE SITE AND LOCAL-ANESTHETIC SPREAD - A PILOT-STUDY, Regional anesthesia, 20(4), 1995, pp. 323-328
Background and Objectives. Stellate ganglion block (SGB) inhibits symp
athetic innervation and is a common treatment for reflex sympathetic d
ystrophy. During the positioning of the needle, there is a risk of inj
ury to the adjacent structures. The aim of the study was to develop an
ultrasonographic imaging technique for the performance of SGB. Method
s. Twelve patients (ASA I-II) underwent SGB first by using the blind s
tandard technique (group A: 8 mt bupivacaine 0.25%) and a second time
by using an ultrasonographic imaging technique (group B: 5 mt bupivaca
ine 0.25%). In group B a 10 MHz ultrasound scanning probe was used to
identify the anatomic structures and to guide the needle toward the tr
ansverse process of C6. Results. Stellate ganglion block was satisfact
ory in 11 of 12 attempts by the blind technique. Ultrasonographic guid
ance (group B) resulted in a complete block in all patients. Onset of
block was observed within 10 minutes in only 10 of 12 group A patients
, while all patients in group B exhibited an adequate block after 10 m
inutes. During the imaging technique, the needle was inserted to an av
erage depth of 22 +/- 3 mm and the injection of 5 mt bupivacaine resul
ted in an anesthetic depot with a mean diameter of 14 +/- 3 mm. Distan
ce from the depot to the vagal nerve was 5 +/- 3 mm and 5 +/- 4 mm to
the root of C6. All patients (n = 4) with a distance of <1 mm between
anesthetic depot and the root of C6 developed paresthesia within the c
orresponding cutaneous segment. Blind technique resulted in hematoma f
ormation in three study patients, with no hematoma occurring during im
aging technique. Conclusions. UItrasonographic guided SGB may improve
safety and allows the visualization of the local anesthetic depot. Stu
dying the local anesthetic spread might allow the avoidance of side ef
fects as well as typical complications of SGB.