Bronchioles (Nursing)

00:00 So bronchioles. Now, these are different than the bronchi. The bronchi are the big ones, the bronchioles are smaller. Now they don't have the cartilage. So that's a key difference I want you to be very aware of. Bronchioles don't have the cartilage that bronchi have. They have this other arrangement. It's kind of cool. Now these are elastic fibers that are attached to the surrounding lung tissues. So the bronchi, are, they stay open because they have that cartilage, but the bronchioles have these elastic fibers that are attached to surrounding lung tissue. That's what helps them keep their shape. So it's inhaled air, not cartilage, that helps support their shape. Okay, so the difference between bronchi and bronchioles. First, bronchi have cartilage. That's what helps keep their shape. Bronchioles, no cartilage. Right? But they have these elastic fibers and what keeps them open is air. So you have to have air for those bronchioles to stay open. Now these elastic fibers expand when filled and then they get smaller when you breathe air out. So with each breath, they're going to go up and down, bigger and smaller, bigger and smaller. Alright, so we've kind of looked a little in depth at the difference between bronchi and bronchioles. Pause the video for just a second, don't look at your notes, and I want you to write quick definitions of bronchi and bronchioles. Make sure you point out at least 2 differences between these structures. Okay, now we're going to look a little closer at the bronchioles. They're the smaller passageways and since they're smaller, the smaller the passageway there's a relatively larger amount of smooth muscle. Now remember I don't really have control of smooth muscle. Right? So it's going to track and expand and I can't really necessarily tell it to. So, we've got the bronchioles and they've got a relatively larger amount of smooth muscle. We've got the terminal bronchioles and the respiratory bronchioles. Now I want you to take a look at the sizes of those two, underline those. So you got 0.5 mm, we have it there for you in inches, we've also got even smaller in the respiratory bronchioles. Now it is not important that you memorize the size of these but I want you to have it very clear in your mind. Which one is smaller, terminal or respiratory bronchioles? Okay, good. Now that we've got that solid, let's keep breaking this down. We've got a graphic for you there where you can see the bronchioles, the alveoli, the capillaries that are wrapped around them that's where we really have the gas exchange happen. We're going to keep moving through the airway just to kind of really break it down. Now I love, there's a drawing for you here because here's what I want you to see first of all. When you look at the drawing, see that we have labeled for you smooth muscle. Okay, that's to remind you there's smooth muscle in the wall and it's also around them. Look at the elastic fibers. Cool, that's what helps expand when you get bigger and then smaller. Then you've got also the capillaries, that's where the exchange is going to happen. So we've labeled some key structures for you to see them all in one spot. So, let's take a look at the first drawing. On inspiration, the volume of those are increased. Right? So you're going to see the walls of the alveoli and terminal bronchioles are going to get bigger, they're going to get stretched and air is brought in. Now, it's just a matter of kind of relaxing (whoooo) because it takes more effort for me to take a breath in than it does to let it out.

03:56 Letting it out is just kind of relaxing. So on expiration, you'll see that volume gets less. Now, take a look at the terminal bronchiole. You see the alveolar wall, you see we've got those bands wrapped around that. That's what helps us with expanding and contracting. So I just wanted you to see this all together in one piece so your brain kind of has an idea of how these all work together.