Transcript for:
Diagnostic Procedures in Pregnancy

Hi, I'm Meris, and in this video, I'm going to  be talking to you about some different diagnostic   procedures that can be performed in pregnancy.  We're going to be talking about nonstress tests,   biophysical profiles, and contraction stress  tests. If you stay to the end, I will tell   you a little bit about my experience with an  NST and a BPP. All right. Let's get started.   Okay. So first up, we're going to talk  about a nonstress test. Let's just talk   about the name first. Nonstress, this means  that we are not actually putting the baby   or the mother under any stress to perform this  procedure. This is just us monitoring what is   happening with the baby inside mom. That is  all. So we're not stressing any of them out.   We're just watching. We're just monitoring.  So a nonstress test means that we are going   to put two things on the mom, in most cases. You  can have a tocometer which is going to measure   the stress that the uterus is under, like is it  contracting at all or not? And then you'll have   the fetal heart rate ultrasound transducer or  the Doppler. It can also be done just with the   Doppler itself. It just kind of depends on what  the provider's setup looks like. In most cases,   mom will also be given a button to push, and that  button should be pushed whenever the baby moves   and mom feels it. Again, not always the case. I  personally have had a lot of NSTs, and sometimes,   I was given the button to push. Sometimes, I  wasn't. But if you ever should see that, then   that's-- the purpose of the button is, "I felt  the baby move. I'm pushing the button," and it's   going to put a little mark on the fetal heart rate  strip to say, "At this moment, mom felt movement."  What are we looking for? So an NST can either be  called reactive or non-reactive. We want it to   be reactive. So what we want to see is something  called an acceleration. We want the baby's heart   rate to increase, to accelerate, by 15 beats  a minute for at least 15 seconds in duration,   two times during the NST, which is going to be  for 20 minutes. So let's say that again. The NST   itself, that test is going to last for 20  minutes, and in that time, we want to see   baby's heart rate go up by 15 beats a minute  and stay elevated for at least 15 seconds,   two times. That would be called reactive, and  that means that it looks like baby is getting   enough oxygen and things are going well. Now, if  we have a non-reactive NST, that means that the   fetal heart rate is not accelerating sufficiently,  and this means that we need more testing. A   non-reactive NST doesn't mean anything by itself.  It just gives us this first thing that says,   "Nope, we didn't pass this test. Let's move on."  So the NST can be done for a lot of reasons. It   can be done, for instance, if a patient says,  "I haven't felt my baby move today." We could do   that. It may be done routinely. This could be done  because a patient is of advanced maternal age.   Maybe they have a history of pregnancy  complications. Maybe they're post-date, meaning   they have gone past their due date. There's a lot  of different reasons that it could happen, but   the point is we're checking in on the well-being  of baby and their ability to properly oxygenate.  Now, let's say we failed that test. It was  non-reactive. We will probably move on to   something called a biophysical profile, a BPP.  In a BPP, you'll see here that we have this nice   table for you to kind of spell out what goes  into a BPP. A BPP-- sorry, it's hard to keep   saying that over and over. This is going to be  using the NST and ultrasound to assess the baby's   well-being. So we have five categories here. We  have the fetal heart rate based on NST. Was the   NST reactive or was it non-reactive? You'll see  here, too, that everything gets a score of either   two or zero. There are no one-point  scores. Okay. So if it was reactive,   we get two points. If it was not reactive, we  get zero points. The next category is fetal   breathing movements. Is the baby making movements  of breathing? Which is something that they do   in utero to practice breathing so that they can  transfer from the uterus to extrauterine life   appropriately. Do we see at least one, if not  more, in 30 seconds? Great. Two points. None?   Then no points. Gross body movements, so if we see  baby moving their body, then they're going to get   two points. If there are greater than or equal to  three body or limb movements, and if there's less   than three movements, they get zero points. Fetal  tone, this has to do with extension in flexion   of the head and neck. So if we do see at least one  episode of extension and flexion of the head and   neck, they get two points. If not, zero points.  And then amniotic fluid volume, they will actually   measure the pocket of amniotic fluid around  the baby. And if there is greater than or   equal to one pocket, so at least one pocket  that has more than two centimeters of fluid,   two centimeters or more, they get both  of those points. If not, then they don't.  So the big things to know, we have the fetal  heart rate NST, we have gross body movements,   breathing movements, the fetal attitude, the  flexion and extension, and then we have the   amniotic fluid as well. What do we do with this  information? Well, 8 to 10 is considered normal,   so that would be reassuring, and we would say,  "Okay, everything looks good." If we have less   than 8, though, that is indicative of fetal  hypoxia. Baby is not getting enough oxygen,   and we need to do something about this. Typically,  that's going to be bringing the baby earthside,   right? We're going to deliver the baby. That may  not always be the case, but that is the cutoff. A   score below 8 means fetal hypoxia could be  possible. Now, if I failed my NST, I could   also go on to have something called a contraction  stress test, a CST. So again, look at the name,   it is saying a contraction stress test. We are  stressing the baby by inducing contractions.   Not inducing labor, hopefully, but just causing  contractions and stressing the baby out that way.   I have only seen this a handful of times since I  started working in OB-GYN back in the early 2000s.   This is not something that is routinely done now  that we have ultrasounds so commonly available,   you could do the BPPs instead, but still  important to know in case you should ever see it.   So what we're going to do here? Same thing.  We're going to be putting the tocometer on   and the fetal heart rate transducer, the  Doppler, and we're going to be watching what   happens to baby's heart rate when contractions  happen. So how do we make contractions happen?   Well, we can either do nipple stimulation, teach  the patient to stimulate their own nipples to try   and release oxytocin to, then, cause contractions,  or we can actually give oxytocin to the patient.  Now, if you remember, this oxytocin is what helps  to cause labor, so we are putting our patient at   risk for preterm labor. We could go from having  just a few contractions to having full-blown   labor, so this is not a test that should be  taken lightly. So in the case of the NST,   remember that reactive or positive is good.  That is not the case here. We want to have a   negative CST. So what this means is that  we have three contractions in 10 minutes,   but we don't see any late deceleration,  and we'll talk about what those decels   are in a later video. But no late decelerations in  those three contractions in 10 minutes? Awesome.   We love it. Baby's doing okay. However, if we  see late decels in greater than or equal to 50%   of those contractions, this could indicate  that the baby's not getting enough oxygen   due to placental insufficiency. Very  bad. We don't like that. So quick recap:   NST, it's not stressing the baby. I want it to  be positive, right, I want it to be reactive.   CST is stressing the baby. It can lead to preterm  labor. It's more dangerous. I don't want it to be   positive. A positive CST is a bad thing. And then  BPP is just using ultrasound, and that is going   to help give us a really comprehensive picture  of what's going on with the baby's oxygenation   status. I hope that review was helpful. Please be  sure to like this video if it was, and if you have   a great way to remember something or something  that I didn't cover that you want to add,   I would love to hear about it in a comment  below. Thanks so much and happy studying.  Okay. So I actually had to get a nonstress test  twice a week with both of my children because of   my genetic condition. They just thought it wise  to check in on the babies. And my daughter, she   failed almost every single one. I mean, she would  never be reactive, and I don't know why, she's   perfectly healthy, but for some reason she just  didn't want to cooperate. One time, she failed,   and I had a BPP done and she scored a six and they  sent me over to the hospital and I had my daughter   via C-section that night. No explanation for  what was wrong with her. She was born perfectly   healthy and fine, didn't spend any time in the  NICU or anything like that, but my doctor said,   "Sometimes, they just do better on the outside,"  and so it was time for her to come that time,   I guess. But my son, though, was a rock star and  passed every single NST, and it was fantastic.   So thank you, Finley, for being an NST rock star. I invite you to subscribe to our channel and share   a link with your classmates and friends in nursing  school. If you found value in this video, be sure   and hit the like button, and leave a comment and  let us know what you found particularly helpful.