In addition to today’s resource from Dr. Rezaie, please review Arterial Lines in Cardiac Arrest by Dr. Scott Weingart.
May 1, 2022
Arterial line waveformso here’s a typical waveform from an a-line i think most of us recognize this and the way the machine reads this is that the top of the waveform ends up being the systolic blood pressure and the bottom of the waveform ends up being the diastolic blood pressure
this is great in a patient who we’re not doing compressions in and here you can see a typical waveform and again top-linesystolic blood pressure bottom line diastolic blood pressure.[Below is an actual monitor tracing in a patient with a spontaneous perfusing rhythm]But what happens in a patient when we’re doing compressions, the waveform looks different. There’s a gray arrow here pointing to a red line and i’ll come back to that in just a second.So at the top of this waveform that’s our systolic bloodpressure [and] that’s great.But the bottom of this waveform is actually the negative intrathoracic pressure from recoil from the chest compression letting up off the chest.What we actually want to be targeting is this line above this shaded red area this is the little dip right before we go into our compression because all this other stuff belowit is incorrect.But the machine doesn’t know that and it reads this as thediastolic pressure so what we want to target is this little notch right before we go into our compression that is actually the diastolic pressure that we’re trying to target.
Outro 2:10 – 2:17This is a really subtle nuanced but veryimportant concept to understand. If youhave any questions let me know and thanks for tuning in