Caveats to estimating EF
Introduction to Bedside Ultrasound Volume 1 &2
Chapters 1-5 are excellent pre-reading for VAPOR
https://itunes.apple.com/ca/book/introduction-to-bedside-ultrasound-volume-1/id554196012?mt=11
https://itunes.apple.com/ca/book/introduction-to-bedside-ultrasound-volume-2/id647356692?mt=11