I always love learning new things to do with POCUS and learning new POCUS skills. Pulse wave Doppler is not a mode that I use often and it is on my list of things to practice with. I think there are a lot of really nice benefits of it in the management of critical illness and shock. Now, at first you may have looked at the title of this post and thought, “I know how to do this, EPSS or fractional shortening. But those don’t use PWD? What gives?” Well, E-point Septal Separation (EPSS) and fractional shortening don’t use pulse wave Doppler, they use simple M-Mode. But, they also don’t measure cardiac output, they measure left ventricular ejection fraction (LVEF), and those 2 aren’t the same.
Matt Siuba explains why we want to measure CO as opposed to being content with LVEF in this video from the Zentensivist YouTube Channel. He also explains everything you need to know about pulse wave Doppler (or at least everything you need to know right now) and how to use it to measure the CO. Don’t worry, there is nothing wrong with your ears, the audio is sped up to 1.25x in order to reduce the time of the video to 14 minutes (this is critical care, time is brain! and heart! and…you know, we’re busy!).