The large intestine is one of the structures of the gastrointestinal system responsible for digestion, it is responsible for final absorption and receives that name because, in contrast to its predecessor, the small intestine, its walls are much thicker and wider; So today we will talk about the first delivery of the large intestine, we divide this very extensive organ into three videos, today we will cover two of its organs, let's put it this way, they are the vermiform appendix and the cecum. This is Dr. Juan Jose Sánchez and welcome to his easy canal anatomy by juan jose sanchez, then the large intestine the current divisions separate it into eight portions from proximal to distal we will talk about a first portion called the cecum of the large intestine, after the cecal appendix the adjective cecal refers to cecum, Also called the vermiform appendix or simply the appendix, these are the two that make up today's video. Then we have the colon, which is in turn subdivided into four portions, an ascending colon, a transverse colon, a descending colon and a sigmoid colon; In the second video before that we will talk about these four portions of the colon and in the final video we will talk about the final two portions which are the rectum and the anal canal. In total, the length of the large intestine is 1.5 to 1.8 meters. You see that it differs quite a bit from the small intestine, which could measure up to 8 meters. So, we have to know that the large intestine is shorter. Let's then elucidate the structures that make it up. to the cecum and the anatomical structures of the vermiform appendix, but first do not go away from the video [Music] I invite you to subscribe here in the lower right corner click [Music] and do not forget to give it the warm side it is important then that you Subscribe to the channel and here you click below and you are automatically subscribed to the channel. 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So we begin first by talking about the cecum, this cecum, you will say: well, what a particular name to begin the large intestine, they say that the cecum is the first portion of the large intestine that goes right from the upper level of the mouth of the ileum, which is the most distal portion of the small intestine, you should already know the small intestine whose videos are posted in the channel, then the cecum is from, let's say, the upper edge of the mouth of that ileum in the ileocecal valve to below, you will say, why? what is called blind? because it is a blind street, it is a neighborhood let's say with a bottom, it is assumed that the fecal matter comes from the ileum and instead of following a path upwards here it falls, fills the cecum and when the cecum overflows it begins to go up through the ascending colon and then transverse colon, so since it is a blind fundus or a blind street, it received the name cecum, so this very particular structure of the intestine who starts it and anatomically we find it inside the right iliac fossa although it is very position variable , since it does not have a structure of the visceral peritoneum, let's say mesoblind, so to speak , that fixes it in one place; So we can find it in some people more ascended on the flanks or even more descended reaching the pelvic portions, but the usual position described is at the level of the right iliac fossa. Now here we have a more specific image, here we see the terminal portion of the ileum and we see that it has two important structures that join on its medial face or more specifically on its posteromedial face, the most superior of which is the mouth of the ileum in the iliocecal junction, cecal is the adjective that defines the cecum anatomically, while in the lower part of that same posteromedial surface is where the vermiform appendix is found or emerges, here we make a cut in the anterior wall of that cecum and in part of the ascending colon and we see the orifices on its middle posterior surface, first the lowest orifice in the appendiceal orifice, which is what continues it with the lumen of the vermiform appendix and we are going to find a structure that joins it to the most distal part of the ileum, that is why we are going to call these folds, which are visceral peritoneum and then it falls through the two structures that it is joined, now here we see that we hold the colon and the appendix with clamps, well the colon or the cecum and we see the back part that remains behind the cecum, we see that it is joined by some folds called cecal folds, which are what connect the cecum to a certain extent to the posterior abdominal wall, at this level there would be the iliopsoas muscle, which is the muscle that is directly related to this cecum; Let's see that all this space is a space, let's say that you can put your hand under the cecum to reach its posterior part until it is stopped by these secal folds, that space is called recess or retrocecal space because it is behind the cecum, now There is an important structure of the large intestine that we will talk about especially when we talk about the colon, which are the tapeworms. These tapeworms are, let's say, elongated muscular structures of which there are three that surround the entire small intestine, like a support for the large intestine. Sorry, let's see that the anterior tapeworm, that there are some books that call it anterior, other books call the free tapeworm, in which the anterior part of the cecum is found; Then we have two posterior tapeworms, one posteromedial or posterointerna, which was also called the mesocolic tapeworm, and one posteroexternal tapeworm, also called the posterior lateral tapeworm, which is also called the epiploic tapeworm. It is said that the three tapeworms converge, join at the back. inferior of the cecum, in fact the vermiform appendix when you look for it anatomically it is found at the union of the three tapeworms, in fact in surgery for us to find the appendix we look in the three lines because it is not so easy sometimes to find an appendix despite You see it there, apparently very easy to locate, in this section we also see this tapeworm, which would be the anterior one, this would be the free one, this would be the internal postero, which would be the external postero, which is the epiploica , and this would be the internal posterior, which would be I had it mesocolic, later when you see the colon videos you will understand why they are called free, mesocolic and epiploic, there is an explanation for that but you won't understand it here, you will understand it well when you see the colon videos. Now we are going to talk about the liocecal valve, which is the valve that is at the mouth of the ileum in the cecum, first the central orifice of this valve is the iliocecal orifice, we are going to see that this valve is made up of two lips, although currently many Authors say that it does not have the shape of a lip, which we will see now; These structures are generally seen in the corpse, now I will explain to you why they are seen in the corpse, then it would be formed by an upper lip and a lower lip, there are places where those lips join which are the commissures, this would then be the posterior commissure and forward we would have the anterior commissures, they are a structure where the lips join and from those commissures come out some folds called cecal folds or frenulums, we would then have the posterior frenulum coming out of the posterior commissure and one that would be surrounding the cecum forward. , in the place that is cut, which would be the anterior frenulum coming out of the anterior commissure, you see this cecum, this cecum is from a living person who remembers that living people have normal intestinal contraction, they have muscle tone; So you see that it has a rather circular shape that even looks like the cervix of a woman's cervix. When the corpse dies, how all those muscles relax is that you see that it adopts that shape of lip and commissure, which is what the texts, about all the anatomical texts, let's talk quickly then about the vermiform appendix, you will say: well, why did they give it the name vermiform appendix? well vermi means worm guys, that's why vermicelli pasta, you see, is the long one in the shape of worms and shaped like; then vermiform because you see it has a shape of helminth, it forms a worm that is why it receives that name but we can also call it cecal appendages because it comes out right from the cecum and remember that it specifically comes out from its medial posterior surface. This vermiform appendage has a very controversial function, some say that its function is to give money to surgeons, but many books actually say that it is a vestige, but it is not really a vestigial organ, even though it does not have an important function, this The vermiform appendix is a lymphoid organ, it has an abundant lymphatic follicle, however removing it from a person does not apparently interfere with any factor in their life and that is why many believe that it is a vestige but it is not really a vestige, remember that I commented at the beginning that the vermiform appendix was located at the junction of the three tapeworms, so you look for their lengths. Some books say 7 to 9, others say 8 to 10 centimeters. Its size is variable and it has a conical shape. What does it mean? that have a conical shape? It has a base that is wide, which is what the cecum sticks to, and a tip that is a little bit, it is not sharp, but if it is blunt, it even has a light inside that we are going to see right now, which is a light that It communicates to the blind man that he is blinder in himself than the blind man because the self is the blind street itself, it is only a light that is full of fecal content, which is a very small light, let's say big, a very small almost virtual light. Now we are going to find it precisely on that internal posterior face of the cecum we see the beginning of the lumen, there in the appendiceal orifice two centimeters from the mouth of the ileal valve of the iliocolic valve, then it will have a structure of the visceral peritoneum that fixed to the posterior abdominal wall, which is the mesoappendix, that mesoappendix is important because when I explain the irrigation, they will see that the appendiceal artery, which is the artery that supplies the appendix, runs through the mesoappendix. It is important in surgery to know that because I know that when I cut the mesoappendix, inside there is the appendiceal artery and I have to take into account that in most cases I will find the artery appendiceal to it, so the tip of the appendix is anywhere that is why it is not So easy to find in appendicular surgery, it is said that the positions can be either anterior or posterior, which is the most common? anterior without a doubt, in the majority of people they have, on the peninsula, an anterior location like here that may be facing the pelvis, we then say that it is an anterior pelvic location or it may be in front of the ileum, which would then be an iileal or anterior location lieal, the posterior locations that are less frequent but that can also be found several times in many people are those that are behind the cecum, which would be in the retrocecal position, one that reaches behind the colon, which would be the retrocolic portion, one that is under the cecum which would be the subsecal position and one that could be behind the ileum which would be the retro skill. These posterior locations are very rare. You already know that the most common is an anterior location and pelvis, the layers of the appendix we are going to see from the most superficial to the deep one, this would be the mesoappendix so that you have an idea. So there are four layers, an external one which is the serosa, then a muscular one, then it joins the submucosa which is important because it is where all these lymphatic follicles are located, which is why they I say that it is a lymphoid organ and it is not a vestigial organ and then the part that is closest to the lumen of the appendix would be the mucosa of the appendix. What is the irrigation of these structures of the cecum and the appendix? Well, it is irrigated mainly by branches of the superior mesenteric artery, remember that this superior mesenteric artery gives the branch of the aorta, so that superior mesenteric artery gives many branches, the one that I care about right now that you learn about is the branch or ileocolic artery, This ileocolic artery that in turn divides into two branches: a colic branch that would be this one that goes upwards and an ileal branch that goes looking for the ileum, the colic branch anastomoses with the right colic artery to help irrigate the colon, but also see here that it grabs downwards and anastomoses with the same ileal branch, helping then to indirectly irrigate the cecum and appendix. Let's talk about the ileal branch, which is the one that I would go to. This structure, first we are going to see here that the ileocolic branch, sorry, the ileal branch of the ileocolic artery towards an arch that ends up joining its former, which is the superior mesenteric artery, from which two arteries emerge that go to the cecum, one that It grabs in front of the cecum, which is the anterior secantella artery, and one that grabs behind the cecum, which in the secant the posterior, of which the most important is the posterior secant artery because it is the one that supplies most of the cecum, in addition to this, Let's see what gives branches to the terminal part of the ileum, which is called the digital ileal branch and one of the most important branches in the ileocolic, many say that it is its terminal branch, which is the one you see here, which is the appendiceal artery. Let them see how it runs through the meso-appendix to supply the vermiform appendix, here we see very well the seca, the posterior, you know that here the majority of the cecum and here you can see the appendiceal artery very well running through the meso-appendix, so This was the entire video of the blind man and the appendix of the report, I hope you liked it, don't forget to subscribe again in the little circle that appears here, that's the only thing I ask of you here, like the video if you liked it and you can follow me on my social networks on Instagram like @juan_sanchez1315