Determining the Learning Curve for Acquiring Core Sonographic Skills for Ultrasound-Guided Axillary Brachial Plexus Block.
The objectives of this study were to determine the learning curve for capturing sonograms and identifying anatomical structures relevant to ultrasound-guided axillary brachial plexus block and to determine if massed was superior to distributed practice for this core sonographic skill.



Ten University of Melbourne, third- or fourth-year Doctor of Medicine students were randomized to massed or distributed practice. Participants performed 15 supervised learning sessions comprising scanning followed by feedback. A "sonographic proficiency score" was calculated by summing parameters in acquiring and interpreting the sonogram, and identifying relevant anatomical structures.



Between the 1st and 10th sessions, the proficiency scores increased (P = 0.043). Except for one, all participants had relatively rapid increases in their "sonographic proficiency scores." There was no difference in proficiency scores between the 15th and 10th sessions (P > 0.05). There was no difference in scores between groups for the first session, (P = 0.40), 15th session (P = 0.10), or at any time. There was no difference in the slope of the increase in "sonographic proficiency score" over the first 10 scanning sessions between groups [massed, 1.1 (0.32); distributed, 0.90 (0.15); P = 0.22) presented as mean (SD)]. The 95% confidence interval for the difference in slopes between massed and distributed groups was -0.15 to 0.56.



The proficiency of participants in capturing sonograms and identifying anatomical structures improved significantly over 8 to 10 learning sessions. Because of sample size issues, we cannot make a firm conclusion regarding massed versus distributed practice for this core sonographic skill.
From the *Department of Anaesthesia and Acute Pain Medicine, St Vincent's Hospital, Melbourne; and †Melbourne Medical School, Faculty of Medicine, Dentistry and Health Sciences, ‡Department of Anatomy and Neurosciences, University of Melbourne, Parkville, Victoria, Australia.
Michael J
MJ
Barrington
Laura P
LP
Viero
Roman
R
Kluger
Alexander L
AL
Clarke
Jason J
JJ
Ivanusic
Daniel M
DM
Wong
D000328:Adult; D059925:Anatomic Landmarks; D000776:Anesthesiology / Q000193:education*; D065527:Brachial Plexus Block / Q000379:methods*; D002983:Clinical Competence; D003479:Curriculum; D004504:Education, Medical, Undergraduate / Q000379:methods*; D005260:Female; D006801:Humans; D059032:Learning Curve; D008297:Male; D013337:Students, Medical; D013647:Task Performance and Analysis; D013997:Time Factors; D018084:Ultrasonography, Interventional; D014739:Victoria