Use of ultrasound in needle placement in intercostal muscles: a method for increased accuracy in cadavers

Abstract

Objective: To validate the use of ultrasound technology for the positioning and leveling of intercostal needle placement.

Design: Double-blinded experimental study.

Setting: An anatomy laboratory.

Participants: Two board-certified physical medicine and rehabilitation physicians, 2 first-year medical students, 1 anatomist, and 8 cadavers.

Interventions: Four unfixed cadavers were used for unguided needle placement, and 3 unfixed and 1 partially fixed cadavers were used for ultrasound-guided needle placement. Ultrasound-guided needle placement was then confirmed with computed tomography and blind dissection.

Main outcome measure: The accuracy of needle placement.

Results: The unguided study showed needle placement in an intercostal muscle 89% of the time, but in only 15.4% of the time was the correct level sampled. In the 96 needle placements completed, the unguided needle placements had an accuracy of 8.3%, while ultrasound-guided needle placements had an accuracy of 93% (χ(2) with P<.005).

Conclusions: Ultrasound guidance dramatically increases needle placement accuracy for intercostal nerve blocks and intercostal muscle sampling for electromyography.