Review of the Anatomy of the Small Intestine and the Sphincter of Oddi (Nursing)

00:01 So you put the fat in your digestive system.

00:04 We put some healthy fats up there. right? We put avocados and some seeds and nuts and salmon.

00:10 That's the kind of healthy fat we should all be gravitating towards.

00:14 But either way we're talking about the dietary fat that we eat, it's not water soluble.

00:20 Well, you know, we work really hard in our body to take things that aren't water soluble and make them water soluble.

00:26 So this dietary fat isn't water soluble.

00:29 So it moves through the stomach as large droplets.

00:33 So take a look at our drawing.

00:35 You see you've got the liver, the gallbladder, the stomach, and then look at the stomach.

00:39 You've got some blobs in there.

00:42 So lipids or fats move mostly undigested in your digestive tract until they reach your small intestine.

00:49 So I chew it up, saliva starts breaking things up with enzymes in my mouth.

00:54 I swallow it, it goes into my stomach, but the fats don't really get broken down until they get in to my intestine.

01:02 So let's zoom in on the space where the bile duct and the pancreatic duct meet.

01:08 Before we do, try and trace that on your finger so you know exactly what we're speaking about.

01:14 Okay, you're looking for the place where the bile duct and the pancreatic duct meet.

01:20 Bile duct coming from up here, pancreatic duct coming out of the pancreas, bingo.

01:26 So let's blow that up.

01:28 Now look at the ampulla.

01:30 Okay, the ampulla is the sack or the dilation where the bile duct and the pancreatic duct meet.

01:38 Now, if I were you, if I wanted to spend the best time studying, get involved with the graphic, put your finger on the screen, put your pencil in your notes, whatever you need to do.

01:49 But this is important because we'll use these structures over and over again.

01:53 So what is the ampulla? Well, it's the sack or the dilation of the opening where that bile duct coming down from above and the pancreatic duct from the side meet.

02:04 Now, the sphincter is a muscular constriction of the mouth of the ampulla.

02:09 Okay. So we talked about the sphincter of oddi.

02:11 That's just like this one.

02:14 And then there's another personal sphincter that I'm not going to show you on film but sphincters have the ability to clamp down and to loosen up.

02:22 So sphincter is the muscular constriction at the mouth of the ampulla.

02:27 That's what controls the bile and the pancreatic juices being released into the duodenum.

02:33 So when you're looking at the picture, can you find all those structures? Can you locate the ampulla? Can you look at the sphincter of oddi? Okay, cool.

02:42 So now you've kind of got an idea of all the things that need to work together when the gallbladder releases what I want that sphincter to be tight or to be open.

02:54 Well, if the gallbladder is releasing bile into the duct, I'm not going to want to stop, I'm gonna want it to drain in the intestine.

03:02 So I'm going to want it to relax.

03:04 See it's that sphincter of oddi that surrounds the ampulla of Vater, that's that small thing that pokes into the intestine.

03:11 So that's where the bile and the pancreatic juices flow.

03:15 If the gallbladder is releasing it and it's flowing down, I need that to be relaxed.

03:22 That's how the bile can enter the small intestine through that muscular like valve.

03:27 So we've used repetition again in this portion.

03:31 I want you to know, do you recognize where the sphincter of oddi is? Do you know what an ampulla is? And do you know what response has to happen to the sphincter when bile is released in order for the food to start to be digested in the intestine? Okay, so we want to show you this again.

03:48 I know, but repetition is a beautiful thing when it comes to learning.

03:53 Look, we've got the big picture for you there.

03:56 You've got the liver, the gallbladder, the stomach, the pancreas, and where it all comes together in the small intestine.

04:04 So I want you to see that space where the common bile duct and the pancreatic duct meet and drain into the small intestine.

04:11 Now, we've given you a window into the intestine.

04:14 You don't really have one of those.

04:16 That's just what you see through the intestine so you know what's going on there.

04:20 The duodenum is where the stomach empties into the small intestine, but let's look at the other parts of the gut.

04:29 Now note, the duodenum, that's kind of the bluish color.

04:32 Now, look where the jejunum is, that's in green.

04:36 And then we end up with the ileum.

04:39 So the duodenum, the jejunum, and the ileum make up the small intestine.

04:44 Those are just names for three parts of the small intestine.

04:48 So where would the stomach be in this graphic? Knowing what you know and what we've discussed about the anatomy, I want you to literally just draw it in so you have clear in your mind where the stomach would be in this drawing.

05:03 Now, let's take a look at the duodenum and the rest of the intestines because the question is, where does 90% of the digestion and absorption of food occur? Well, most of the end absorption of nutrients and minerals from food takes place in the small intestine.

05:21 Usually people think it's their stomach but it's not.

05:24 It's why the intestines are so important.

05:27 90% of it in the small intestine, the other 10% of it in the stomach, and the large intestine.

05:33 They share that percentage.

05:35 So that's why the small intestine is so important.

05:39 You'll see it there. We've got it marked off for you.

05:41 The duodenum, jejunum, and the ileum are all parts of the small intestine.

05:47 Then we've got the large intestine and the rectum which is just kind of a holding tank for waste before it exits your body.