Written by Chris Thom
Spoon Feed
In this randomized control trial comparing standard ultrasound to biplane ultrasound for peripheral IV access, medical student users had fewer vessel back wall punctures when using biplane imaging.
An innovation for access
This was an RCT comparing biplane and traditional imaging with 98 fourth year medical students, 51 in the biplane arm and 47 in the traditional arm. Students had ultrasound guided IV (USGIV) training on a phantom gel block using their randomly selected imaging technique. Following this, students were evaluated on USGIV placement on the phantom gel model. Students then switched to the alternate imaging modality to gain exposure to both techniques.
85% thought biplane was more effective. The average time to successful placement was 64.4 seconds (SD 43) biplane and 73 seconds (SD 37) traditional, p=0.29. The mean number of needlesticks was 1.10 (SD 0.3) in the biplane arm and 1.06 (SD 0.44) in the traditional arm, p=0.65. The average number of posterior vessel back wall punctures was 0.14 (SD 0.4) biplane and 0.45 (SD 0.8) traditional, p=0.02. On a 1 to 9 Likert scale, with 1 (prefer biplane) and 9 (prefer traditional), the median was 3 (IQR 2-4).
How will this change my practice?
Biplane ultrasound imaging is an innovative feature that is available on certain manufacturers and/or ultrasound probes. In the case above, the long axis view is a complete view, while you get a single “slice” of the short axis view that you can set via the green vertical line (see image below). Visualizing both at the same time is an attractive option, particularly for more novice users with lower skill at following the needle tip in the short axis. Given the reduction in back wall punctures seen here, there may be an important patient safety benefit, particularly as these findings have also been seen in central line placement.
POCUS pro-tips:
The USGIV is the unsung hero of EM practice. As we’ve seen nurses and ED technicians become more facile with this procedure, it is important to appreciate its ongoing importance for the practicing emergency physician and resident trainee. A well-executed USGIV will save you and your patient in many scenarios where an IO might not be appropriate (e.g. – stroke alert needing CTA). And the fundamentals of ultrasound needle guidance learned via USGIV skills are identical to those used for ultrasound-guided central lines, arterial lines, regional anesthesia, arthrocentesis, etc. If you strive for excellence in your ED procedures, spend the time to become a wizard with USGIV placement. Biplane imaging may have an additional role here.
Source
Thom C, Han D, Vann G, Martindale J, and Moak J. A Randomized Study of Biplane Imaging in Ultrasound-Guided Peripheral Vascular Access Performed by Novice Operators. The Journal of Emergency Medicine, 2025, ISSN 0736-4679, https://doi.org/10.1016/j.jemermed.2025.02.016.
