Ultrasound provides a reliable test of local anesthetic spread.
OBJECTIVE
We predicted that practitioners could identify injectate spread in a model of ultrasound-guided peripheral nerve block.


METHODS
Both novices and experts in ultrasound-guided peripheral nerve block were asked to recognize the spread of local anesthetic in a gelatin ultrasound phantom. In a blinded and randomized fashion, these participants were observed to either successfully or unsuccessfully state whether an injection had been made.


RESULTS
Twelve novices and 8 experts each completed the trials. Accuracy, Sensitivity and specificity were calculated for all trials. Users attained a very high accuracy and sensitivity (> 85%) as well as specificity (> 90%) with ultrasound in this model.


CONCLUSIONS
This study shows that ultrasound is a reliable method of detecting injectate spread in a gelatin phantom model.
McCartney
Colin J L
CJ
Department of Anesthesia, University of Toronto, Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Toronto, Ontario M4N3M5, Canada. colin.mccartney@utoronto.ca
Dickinson
Victoria
V
Dubrowski
Adam
A
Riazi
Sheila
S
McHardy
Paul
P
Awad
Imad T
IT
D000779:Anesthetics, Local / Q000008:administration & dosage*; D002983:Clinical Competence; D005780:Gelatin; D006801:Humans; D007267:Injections; D009407:Nerve Block; D009864:Ontario; D019047:Phantoms, Imaging; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional / Q000295:instrumentation
D000779:Anesthetics, Local; D005780:Gelatin