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Published on: March 6, 2019
Impact of Predefined Angles and a Revised APPLES Mnemonic on Accuracy and Performance Time for Simulated
John W Norbury1, William Brader, Michael McIver
1From the Department of Physical Medicine and Rehabilitation, The Brody School of Medicine at East Carolina University, Greenville, North Carolina (JWN, WB, MM); Department of Academic Affairs, The Brody School of Medicine at East Carolina University, Greenville, North Carolina (SCC); Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Hospital, Baltimore, Maryland (VS); and Department of Emergency Medicine, The Brody School of Medicine at East Carolina University, Greenville, North Carolina (KMR).
Objectives:
Our objective was to determine whether predefined angles would improve performance time and accuracy of ultrasound-guided procedures by novice operators and whether a revised APPLES (approach, position, perpendicular, lift, entry, sweep) mnemonic was a helpful guide for performing the procedure.
Methods:
Participants attempted to hit targets in-plane and out-of-plane at different depths with a needle under ultrasound guidance with and without predefined angles. Participants were then asked if they thought that the mnemonic would be helpful when learning both methods for ultrasound-guided procedures.
Results:
There were 120 participants all of whom had performed fewer than six ultrasound guided procedures. Accuracy increased in all groups when angles were provided; however, only the 3-cm in-plane approach achieved statistical significance. Performance time also achieved statistical significance in two of the four groups. Ninety-five percent of participants thought that the revised APPLES mnemonic would be helpful for learning and performing ultrasound-guided procedures in the future.
Conclusions:
Predefined angles seem to positively impact procedure time and accuracy for some target depths, and the APPLES mnemonic could be a helpful mental checklist for many novice operators. These may be useful tools to facilitate safe and efficient ultrasound-guided procedures in the clinical space.
