Changes in Cardiac Reserve and Baroreceptor Function (Nursing)

00:01 So with all that being said, is Jose like a superhero? No, not really, but he has stayed active, and he's made really healthy lifestyle changes and he has good genetics, don't forget that.

00:13 That is one of the non-modifiable factors but I want you to also keep in mind that only the cardiac reserve declines in normal aging.

00:23 Now, that's important enough that I want to say it again.

00:26 It's only the cardiac reserve that declines in normal aging.

00:31 Now, let me show you some pictures to help you understand what cardiac reserve is.

00:36 So see here, we have young Jose, his heart is pumping, and you see that we have a full graph that represents the maximum capacity for pumping blood.

00:45 Okay, so the red part is the cardiac output, the white part is the extra reserve that you have in case that heart is pushed to its maximum.

00:55 The actual definition of cardiac reserve is the difference between the rate the heart pumps blood at rest, and its maximum capacity for pumping blood.

01:03 Okay, so let's look at that with some pretty cool pictures.

01:07 So here we have both Enrique and Jose.

01:10 Now, here they are at rest, right, and you see where their cardiac reserve is.

01:15 Now let's have them do some jogging in place, watch what happens to their cardiac reserve.

01:21 Alright, see, they're pushing themselves a little bit more with their activity, but they're able to respond, and they still even have some extra reserve left.

01:30 Now, let's fast forward to our older Enrique and Jose.

01:35 Now look at the difference right there between Jose and Enrique's cardiac reserve.

01:40 Who has more? Jose has more cardiac reserve.

01:46 So what does that tell us about Enrique? He just doesn't have much margin for stress, or physical stress, right? Because he just has this much more than his heart can give.

01:58 Whereas if you look at Jose, it's almost doubled in this example.

02:02 So let's have them be a little active and see what happens.

02:06 Well, Jose still has a little bit left to give, he's working at a normal pace but look at Enrique, he is redlined all the way up.

02:15 He had less reserve to start with and it doesn't take much for him to max out his heart rate.

02:22 So why is it harder for elderly client's heart to respond to stress with an increased heart rate or an increased cardiac output? Now, it may seem obvious to you like yeah, we knew before we watch this video series, that older people don't have as much energy, but I really want you to understand why.

02:40 Cardiac reserve is important to that, but there's also some other factors.

02:45 Baroreceptors play a really important role in the heart and cardiovascular function.

02:51 Now, you might wonder, why do we have Jose laying down? because we wanted to remind you that the baroreceptor function helps a patient maintain a stable blood pressure when they go from lying to sitting, or sitting to standing.

03:06 Now, you may have had a patient who's on a blood pressure medication, and we're worried about the side effect of orthostatic hypotension.

03:13 That means when they go from lying to sitting or sitting to standing, we ask them to do that slowly, because it gives their body time to adjust and stabilize that blood pressure.

03:25 Well, what's driving that whole response are the baroreceptors.

03:29 Now we've got a great graphic for you there.

03:32 So see, we have the baroreceptors labeled, we know that they're also on the aortic arch.

03:36 That lets you know how it communicates back up with the brain.

03:40 So when a young person, this functions beautifully.

03:44 They're not usually at a risk for orthostatic hypotension, unless they're on a specific medication.

03:49 So there they go.

03:51 Look at what happens, watch those signals come right down and tells the body what to do as far as constricting the vessels or dilating the vessels.

04:01 Now, as you age, even successfully, the baroreceptors don't function as well.

04:06 Let's say they have a decreased function.

04:08 So in an elderly client, same kind of experience, watch how this response happens.

04:15 Yeah, see that? it's impaired.

04:18 Now, I'd encourage you to even go back and compare normal to impaired response in the video so you have that clear in your mind.

04:25 This is another reason that of the changes that you experience in cardiovascular function as you age.

04:32 So when you have this decreased function, you see that we have those squirrely signs around his head.

04:37 That's because an elderly person is more at risk for orthostatic hypotension, which puts in an increased risk for falls, even Jose, who's age successfully and just has the normal changes from aging.

04:51 He's had an increased risk for orthostatic hypotension and increased risk of falls.

04:56 So think of the risk that Enrique is out because he has the additional challenges