Early, Late, and Variable Decelerations (Nursing)

00:01 Look at this first pattern. This is called an early deceleration. Let's talk about why? So we're looking at the fetal monitor and what we see on the top is the fetal heart rate and the bottom is the contraction.

00:14 How would you describe the relationship of the decrease in the fetal heart rate with that contraction? Do you see the onset of both the contraction and the deceleration and the lowest point and the recovery? What do you think about that? Exactly, they seem to almost mirror each other.

00:33 They happen at the same time, so the contraction somehow is affecting the fetal heart rate.

00:41 So this particular deceleration is called an early deceleration and it's caused by head compression, so if Clitus's head is being squeezed, then the heart rate goes down. This looks bad, but actually, it's very normal.

00:56 Think about squeezing your head that might make your heart rate go down, too.

01:00 But when the baby's head is squeezed, i.e. it's coming through the birth canal, that's perfectly normal.

01:06 So, early decelerations, even though they looked kinda scary are actually okay.

01:11 So here's the question, is it periodic or is it episodic? Exactly, it's periodic because it happens because of the contraction, the relationship is there.

01:28 Alright, let's move on to the next one.

01:31 So first, just take a second and look at what is happening and think about how this looks in relationship to the previous slide? Do you notice that the onset of the deceleration in the heart beat is not exactly matching up with the contraction, it happens after the peak of the contraction. Do you see that? And then it gets to the lowest point at the end of the contraction and the contraction is over and then finally the heart rate begins to come back up to baseline, so the response is delay.

02:03 So what that's telling you is that perhaps the oxygenation status or the blood flow, something is not quite as it should be, because these things should either not happen at all, either there's no deceleration or it should happen at the same time.

02:17 This is a delayed response and it indicates that there is poor sufficiency in terms of blood flow between the placenta and the umbilical cord and the baby.

02:28 This is a late deceleration and it's an indication of poor oxygenation.

02:33 So of course my next question is, is it periodic or episodic? Is it happening because of the contraction or not? You got it, the answer is periodic.

02:50 Okay, let's move on.

02:54 So let's look at this third type of deceleration and let's talk again about what is different.

03:00 Now the first thing you may notice is that it's very short in terms of when it starts and when it gets to that lowest point, that's a very rapid decent, it's less than 30 seconds if you need sort of a quantitative measure, so it's not as wide as the early or the late decelerations that we looked at, that is characteristic of a variable decal - it takes less than 30 seconds to go from the onset to the nadir or the lowest point.

03:27 And it might recover right away, it might take 30 seconds to recover.

03:32 The other side of it is really unimportant.

03:35 The only thing that's going to establish that this is a variable is that it takes less than 30-seconds to go from the onset of the deceleration to the nadir.

03:44 Now, in this case, we see it happening in relationship to the contraction, it seems like it is anyway, but variable decelerations are actually caused by cord compression and cord compression can happen for any number of reasons.

03:58 So yes, when you have a contraction, if the cord is lying up next to the baby's cheek, it may be compressed and give you a variable deceleration.

04:06 But if you think about a newborn, they also have a grasp reflex and if you put anything into their hand they will squeeze it and that includes an umbilical cord.

04:17 So to give you an example, if we have Clitus, Clitus is just hanging around in the amniotic sac and the cord just floats by and happens to land in Clitus's hand, Clitus is going to squeeze said umbilical cord and he will continue to squeeze the umbilical cord until he passes out, at which time he will let go. The oxygen will flow back into Clitus and he will wake up and be nice and refreshed and then realize, oh, there's a cord in my hand, I must squeeze and we could go through this over and over and over again, so this might be one of the reasons for cord compression.

04:56 There also may be cord compression because the cord is wrapped around the fetus's neck and that is called a nuchal cord and that may or may not affect it's relationship to the contraction.

05:06 So I want you to understand what I'm saying, there are lots more reasons for variables aside from a contraction so that leads me to your question, is it periodic or is episodic. What do you think? Guess what, it could be either one.

05:28 It could be periodic or episodic depending on the reason it occurs, so you got that one right, I hope.