(This post first published on blog.5minsono.com on November 4, 2015)
The FAST exam is an examination that is ubiquitous in emergency medicine, and the more I do them, the more I realize that their correct interpretation takes some training. If you don’t know how to properly do a FAST exam, START HERE. The following is a list of things that will cause you to have a false-positive or false-negative FAST:
Right upper quadrant:
- Perinephric fat
- Gallbladder
- Not looking at the inferior pole of the kidney/caudal tip of the liver interface
Pelvis
- You’re too high (probe should sit right above the pubic symphysis)
- Iliac vessels
- Probe not oriented sagitally
Left upper quadrant
- Perinephric fat
- Stomach
- Not looking superior to the spleen
Here’s a video summary: