End diastolic Flow

[Tink2007]

What is the difference between Enddiastolic Flow: Negative and Enddiastolic Flow: Positive? Does anyone know? And also, what is it?

I assume you mean in the umbilical artery? But it could refer to any blood vessel measured. The best way to understand it is to sit with an obstetrician and get them to draw you a picture or show you the scan picture. But I’ll try! Essentially, systole is when the heart squeezes to pump blood around the body, and diastole is when it relaxes and so isn’t pushing the blood from the heart out through the arteries as strongly. When it is measured in pregnancy, essentially the scan generates a waveform on the screen, where the speed of blood flow in the artery is measured. Faster speed happens in systole (the squeeze) and slower in diastole (the relax) which looks like a wavy line on the screen. If the end diastolic flow is positive, it means the blood is still flowing forwards in the artery when the heart is fully relaxed. That’s how it should be - but there can still be abnormal level of forward flow (ie positive but slower than it should be). If end diastolic flow is negative then that is abnormal and means baby is struggling. When it’s done in the umbilical artery, it’s essentially a measure of resistance in the placenta - how hard baby is having to work to circulate blood to the placenta. It can be used to time delivery (eg if UA EDF is negative after 32ish weeks, baby usually requires delivery, if before 32 weeks additional monitoring is done). Does that help or have I confused you more??