PALS Primary Assessment – Circulation

Hi, everyone. We’re still in primary assessment, and now we’re going to be talking about circulation, assessing this child’s cardiovascular status—how well are they moving oxygenated blood throughout the body? What measurements are we going to be taking? We’re going to be looking at their heart rate, pulses (both peripheral and central pulses), capillary refill time, blood pressure, but we’re going to start with the easiest thing to assess for and that’s their color.

We can do this as soon as you see the kid. What are we looking for? A nice, pink kid. Pale skin: This could be natural for some kids. Little Irish kids—I’m half Irish—are generally pretty pale. They’re light skinned. It can also be a sign of hypoperfusion, hypovolemia, poor circulation. Mottling can happen with poor circulation. This is kind of a blotchy skin tone we see on the child. Hypoxia, bluish—this is a big deal. In order to develop cyanosis, that bluish tint to a child or to any human being, this requires 5 g of circulating deoxygenated hemoglobin. Why is that a big deal? Because it depends on how much hemoglobin they had to start with. If they were already low—say their hemoglobin was down to 8—and they’re cyanotic, they’ve lost over half of their hemoglobin, their oxygen-carrying capacity. That’s a big deal. A child or an individual who may have polycythemia, an increased number of red blood cells, has a little more wiggle room when they develop cyanosis. They still have some hemoglobin to carry oxygen in reserve despite the cyanosis. Regardless of that, our first step is to administer oxygen. Remember, in our primary assessment, we’re looking for life threats. As soon as we see a blue child, that’s a life threat. We have to stop what we’re doing and fix that cyanosis, which includes the immediate administration of high-flow oxygen. We have to begin oxygenating that child.

Pulses: It’s important to remember when assessing the pulse rate in a child that we take it over about 30 seconds. The reason is that a child can have a normal variability in their pulse rate. It can come up and come down a little bit. We want to take it over a long enough time that we get an accurate reading. In the adult, take it for 15 seconds, multiply it by 4, and we get a pretty good pulse rate. For a child, at least 30 seconds.

Capillary refill time: Capillary refill time is used to assess how quickly after we blanch the surface of the skin it pinks up again. We like to see less than 2 seconds. In a child, one of my pediatric gurus told me years ago that the soles of the feet are the window to the heart. Makes sense because the soles on the feet of a child are the farthest distance away from the heart. The child has to be supine. Raise the leg up slightly, blanch the bottom of the foot, and look for that capillary refill time. Again, it should be less than 2 seconds. If it’s greater than that, we may have some perfusion issues.

Blood pressure: For all my EMS buddies out there, you’re saying, “Gee whiz, we don’t usually do blood pressure until the secondary assessment,” and you’re absolutely correct. However, right now we’re still talking about the different items that we go through when assessing perfusion on a child and their circulatory status, and blood pressure is definitely one of them. You’ll hear people say, “Oh, a blood pressure not important to take in a child or an infant.” Wrong. It is absolutely important to take in a child or an infant. However, know this: A child will compensate with their heart rate to maintain that blood pressure until they can no longer compensate, and then the blood pressure will fall right off a cliff. As opposed to an adult that you may see a more gradual decline in their blood pressure, kids compensate and ‘pft’ right off a cliff. So, absolutely, take a blood pressure. Additionally, make sure that you’re using the right size blood pressure cuff on this child. Look at the markings on the cuff. There are markings on any blood pressure cuff that tell you the size of the cuff to make sure it’s a proper fit for that extremity. If you use a cuff that’s too large, you’re going to get a falsely low reading. A cuff that’s too small can give you a falsely elevated reading or a higher reading. Make sure you’re using the proper size cuff on every patient, but absolutely on a child. When it comes to blood pressure, heart rate, pulse rate, we have all these numbers that we have to try to remember. For blood pressure, I just try to remember what’s hypotensive, right, what’s bad. In a neonate, in the first 30 days, a systolic blood pressure below 60 they define as hypotension. From 30 days to 1 year old, a systolic less than 70 they call hypotension. From 1 to 10 years old, it’s 70 plus 2 times a child’s age. If it’s less than that, it’s defined as hypotension. After 10 years old, we want to see a systolic above 90. Now you can see where this blood pressure comes into play. If I take an initial blood pressure on a 4-year-old, right, and it’s 50, that’s too low. I already have a low blood pressure, and I should be seeing all the signs of compensation—the fast heart rate, tachypnea—but it gives me a starting point. If that 4-year-old had a blood pressure of 80, okay, I have a little wiggle room here. It sets the bar. It sets my baseline blood pressure so at least I know where I’m starting at. That’s why you want to get a blood pressure in a child.

Talking about pulses and heart rate, again, we’re going to assess the pulse for about 30 seconds. As soon as we can, after our primary assessment, we’re going to put this child on a cardiac monitor. We want to correlate the reading on the cardiac monitor with the pulse we’re actually feeling. This way we have one eye on that heart rate the whole time, and we can start monitoring their heart rate off the cardiac monitor. First, we have to correlate that with the pulse that we’re feeling. When assessing the heart rate, there are really only three things that it’s going to be: too fast, too slow, or not there at all. Too fast: tachycardia. Too slow: bradycardia. Not there at all: asystole. Asystole actually means without pressure. It really doesn’t mean electrical activity on the monitor. It means without pressure. Asystole: a- systole (without pressure). Fast heart rate: I remember these three numbers, and these are the upper limits of tachycardia for the adult, child, and infant: 150 for the adult, 180 for the child, and 220 for the infant. These are the numbers we want to put in the back of your mind. If the tachycardia is less than those numbers then we’re looking for a cause. What is causing that heart rate to be fast? Is it dehydration? Is it blood loss? Did the tank get bigger—are they having an allergic reaction? If the tachycardia is greater than that number, more beats per minute, then we’re going to start looking at the heart. Is this an SVT—is this a supraventricular tachycardia? Is the heart the culprit? Not dehydration, now it’s the heart. Any heart rate in a child out of the normal range is a bad thing. Tachycardia is a bad thing and we need to find the cause and fix it, but bradycardia is an ominous sign. The child can arrest from this. Any slow heart rate in a child is cause for immediate concern. On our initial assessment, if we find a very slow heart rate, that’s a life threat. We have to address that immediately. If despite oxygenation and ventilation, this child remains unresponsive with a pulse rate less than 60, we’re going to need to begin chest compressions. We talked about the upper limits of tachycardia. Keep that number 60 in the back of our mind for bradycardia. Any pulse rate less than 60 despite oxygenation and ventilation, be prepared to start chest compressions.

Later on, once the child has been admitted and they’re in the hospital, we’re also going to assess the renal perfusion. We’re going to put a Foley catheter in, and we’re going to take a look at their urinary output. Obviously, we’re not doing this during our primary assessment, but this is a valuable tool to look at the overall perfusion status of the child. A small child should make between 2.0 and 1.5 cc/kg/h of urine. That’s what we want to see. That tells us that we’re perfusing the kidneys. We have good core perfusion. We’re perfusing the kidneys.

This has been just a quick review of the highlights of the circulatory component of the primary assessment. Thank you for watching. I’ll see you in the next video.