Maternity - Newborn, part 3: Infant Reflexes, Heel Stick, Lab Tests and Prophylacticat Birth

November 23, 2021 Updated: January 17, 2022 9 min read

Full Transcript

Hi, I'm Meris with Level Up RN, and in this video, I'm going to be talking to you about reflexes in the newborn, the heel stick procedure, and some medications that are commonly administered after birth. I'm going to be following along using our maternity flashcards here. These are available on our website,, if you want to get a set for yourself. And if you already have your own set, I would invite you to follow along with me. All right, let's go ahead and get started.
So first up, we're going to be talking about primitive reflexes. So just across the line, all of these reflexes that we're talking about are going to be present from birth. Now we do have these nice tables here for you with lots of information as to what the name of them are, how long they persist, and what the exact description of them is. So if you want more information, I would encourage you to look at these flashcards. But a big one here is going to be the Moro or startle reflex. This one disappears usually around two months. If you've ever seen an infant, you have probably observed this reflex. This is going to be that they extend their arms, then they bend them in, and kind of cry in response to a sensation of falling or to being startled like a loud noise or sudden movement. So the baby is always sleeping. They're just having a good time, whatever. Then either they feel like they're falling or they hear a noise, and they put their arms out like that, right? I always feel like they shake. They kind of extend their arms, and then they're, "Ahh," because I mean, it's scary. It's startling. So this is a very common one that you will observe in the infant.
Walking or stepping, this is where if I'm holding the baby up, here's my trusty doll, Molly. If I hold the baby up and put her feet on a flat surface, her feet will sort of extend as though she is stepping or walking. She cannot actually bear weight, right, but this is a protective reflex. Rooting, this is where the infant is kind of searching, right? Their cheek and mouth might get stroked, and they're going to turn their head thinking like, "Is there food there? Can I get some food, please?" So my daughter had a really exaggerated rooting reflex, and we used to call it ostriching because when we would hold her if she was really starting to get hungry and I was preparing-- I was warming up my breastmilk that I had pumped, her dad would be holding her like, "It's okay. Mommy's getting it." And she would just be like this. Her head was just bobbing around because literally, it's this idea of if I move my head enough, will a nipple fall into my mouth? Can I find that nipple? So that's what that rooting reflex is, or in my family, we called it ostriching. Sucking reflex, so when the lips are touched, the infant is going to start that sucking maneuver, right? Again, we're very food-centric as infants. Premature babies may have a weak sucking reflex, though that may not be fully developed.
Some other reflexes that you may see, palmer grasp. If I put something in the hand, in the palm of the baby, they're going to grab onto it very tightly. So if you've ever been around a newborn baby and you're stroking their palm and they grab on, and you're like, "Oh, it's so cute," I hate to break it to you, it's just a reflex. Tonic neck reflex, this is where the head is turned, and the infant extends the arm and leg on the same side, or the ipsilateral side, meaning the same side, while the contralateral, the opposite side arm and leg flex inward. So I turn the infant's head this way. This arm and leg go out, and this one comes in, and this is sometimes called fencing position. It looks like they are going to-- if you've ever seen fencing, it's like we have one arm is extended and the other one holds the thing. So it looks like they're fencing. Plantar grasp is the same idea as palmer grasp. If I put something up against the base of their toes, their little toes will curl inward around that. And then Babinski reflex, this one is important because it's important that the Babinski reflex be positive in a newborn, whereas if I have a positive Babinski reflex, something is very wrong neurologically. So this lasts until about 12 months of age and when the lateral aspect of the plantar surface or the outside of the sole of the foot is stroked in this upside-down J motion, the infant's toes are going to dorsiflex and fan outwards. So fanning outwards and dorsiflexing coming up like that versus plantar flexing, going down. So dorsiflex fanning out, that is going to be a positive Babinski sign, which is a good thing in an infant, a bad thing in an adult.
Okay. Moving onto the heel stick procedure. So I just want to show you we have a really nice illustration here as well. So the heel stick procedure, it's pretty easy to draw blood from an adult. It's not so easy to draw blood from an infant. So instead, we stick the heel to collect blood. Now again, remember, we are adjusting to life outside of the uterus. Our circulation is not as great as it is in an adult, so we're going to want to start by warming the heel, and there are specialized heel warmers you can use. You could put a warm blanket around the heel, but we want to increase circulation to that area prior to sticking it so that we can get better blood flow from it. We're going to think of it sort of like when we do a capillary blood glucose. We're going to cleanse the area with alcohol and allow it to dry fully. And then we have lancets that we will use to puncture the surface of the heel. And these are actually specifically made for heel punctures, so they are a little bit longer of a puncture than for a capillary blood glucose. And then that's where we're going to really squeeze that heel pretty well to try and get some blood out of there. So I want you to see that here in this green area on either side is where we would want to stick the infant. We're not sticking right in the middle of the heel. We are most certainly not sticking anywhere else in this foot. We are sticking on the lateral aspects of the sole of the foot here in the heel region. That's going to be the best place and also the least painful as well.
So what sort of tests do we do for the infant at birth? Well, most genetic screening is happening between 24 and 48 hours of birth, typically at that 24-hour mark. And there are screenings that are state-mandated. So this is by law. These have to be done. And typically, they include metabolic screenings for things like phenylketonuria, PKU, congenital hypothyroidism, galactosemia, and sickle cell disease. There's also some testing that can be done, again, state to state to check about circulation. So making sure that the circulation seems to be in line with what we would expect. There can also be audiological screenings done to ensure that it appears that the infant is able to hear. Those sorts of things may be done as well. So now remember, PKU, phenylketonuria is a genetic disorder wherein high amounts of protein can actually lead to death, so this would be something where you would really need to educate the child's family about this finding.
Okay. Lastly, I want to talk to you about medications that are routinely administered after birth. This isn't on this card, but in the biz, you might hear this called eyes and thighs, right? This is very, very common. So there's three medications that we routinely administer. The first is going to be the erythromycin ophthalmic ointment. So this is an antibiotic that is applied into the eyes of the infant. And the reason for this is it's prophylactic meaning to prevent a condition called ophthalmia neonatorum. This is a certain type of condition that can occur in the infant if they are exposed to gonorrhea or chlamydia during birth, like coming through the birth canal. The reason we do this prophylactically is, yes, we do very-- we test the pregnant patient for gonorrhea and chlamydia, but it's possible to develop it later, right? And then also, what if this were a patient who didn't have prenatal care? We don't know their status. And also remember that gonorrhea and chlamydia are typically asymptomatic, so the pregnant patient may not even know that they have this condition. So prophylactically, just to prevent this, we give it to, essentially, every newborn unless their parents refuse.
So those are eyes, right? We put it in the eyes. Now let's talk about thighs. We have two medications that we deliver via injection, intramuscular injection. The first is vitamin K. Now, vitamin K is very, very, very important for clotting, and vitamin K doesn't cross the placenta very well. And it also doesn't come through the breastmilk very well, either. So this is very important to help a newborn with clotting is to give them that sort of first exposure to vitamin K so that they can get those clotting factors taken care of. And they don't produce these sort of-- they don't produce enough vitamin K themselves until about day eight. Well, so yeah, they may not be climbing mountains and stuff and doing things where they might fall and hurt themselves, but they just went through a potentially traumatic birth, right? So we could have bleeding in the brain without even knowing it for a little while. And it's very important that we have enough ability to clot. So vitamin K is so important for clotting. So this is given IM in the vastus lateralis, the thigh. So there's your first thigh.
The second thigh is going to be for the hepatitis B vaccination. This vaccine is going to be given routinely at birth, and then we give boosters again throughout infancy. It's given at birth, one or two months, and then between six and 18 months. And the thing that is important to know about this is that because it is a vaccination, it does require that informed consent to be signed. So of the three things, hepatitis B vaccination requires a signed informed consent from the patients. It's here in black and white or big, bold red letters, Meris. And that means that it's really important for you to understand because we have to be getting informed consent from the parents. We don't want to administer it in the same thigh as vitamin K for a couple of reasons, first is these are small muscles that can only take a small volume. And the second is you'll see, routinely, hepatitis B and vitamin K are usually administered in the same thighs every time. So left is always vitamin K. Right is always hepatitis B or something similar. That way, we can assess for any kind of reaction as well. And if we see that it's happening, that we have a reaction, we have swelling, something like that, well, if we gave them both in the same thigh, how are we going to know what they're reacting to? Now, if we have an infant who was born to a hepatitis B infected mother, then what we want to do here is give hepatitis B immune globulin and the hepatitis B vaccine to the infants within 12 hours of birth. So that's kind of an important distinction there versus a child born to a non-infected patient. So eyes and thighs, that's going to be how you can remember the three medications that we give routinely to infants after birth.
I hope that review was helpful for you. I'm going to ask you some quiz questions so that you can gauge your understanding of some key facts that I gave you in this video. All righty. So first up, my question for you is by what age should the Moro reflex disappear? We talked about that Moro reflex, but when should it go away? My second question is that you are the nurse and you're assessing an infant, and you notice that when their head is turned, they extend their ipsilateral arm and leg. However, their contralateral arm and leg flex inward. What is the name of this reflex? And lastly, my question for you is, which three medications are routinely administered after delivery? Thanks so much and happy studying.

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