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1、Section 6 结肠下区 Infracolic Compartment,Infracolic compartment lies between transverse colon with its mesocolon and superior aperture of lesser pelvis.,It contains jejunum, ileum, cecum, vermiform appendix, colon and other viscera.,I. 空肠及回肠 Jejunum and ileum I)位置 Location Jejunum and ileum are continu
2、ous coiled part of small intestine, extend from duodenojejunal,flexure to cecum and occupy most part of infracolic compartment. They probably average about 56 meters in length.,Jejunum comprises upper 2/5 of whole length, and ileum lower 3/5. Jejunum located upper left abdominal cavity and ileum in
3、lower right. The small part of ileum usually passes also into pelvis., Meckel憩室 (Meckels diverticulum) Persistence of proximal portion of yolk sac (vitelline duct) common malformation of digestive tract (24%) more prevalent in males. About 25cm long and located 30100cm from ileocecal valve. Usually
4、asymptomatic but: May become,inflamed (mimicking appendcitis) or cause intestinal obstruction by compressing adjacent intestinal loops., II)肠系膜 Mesentery It consists of two layers of peritoneum, and contains jejunal and ileal blood vessels, as wall as lymph nodes and some fat. Mesentery is fan-shape
5、d and allows coils of intestine considerable freedom of movement.,Root of mesentery begins from duodenojejunal flexure, which somewhat at left side of second lumber vertebra. Its line of attachment to posterior abdominal wall extends obliquely downwards and ends to ileocolic junction, which is appro
6、ximately at level of right sacroiliac joint. It is about 15 cm in length., III) 血管 Blood vessels Entire jejunoileum is supplied by branches of superior mesenteric a., which arises from,abdominal aorta at level of L1, posterior to neck of pancreas. It descends anterior to horizontal part of duodenum
7、and enters root of mesentery to right iliac fossa. It gives off 1218 intestinal arteries from its left side to jejunoileum.,Jejunal and ileal arteries branch and anastomose with each other to form a series of arterial arcades, from which further branches,form a second, a third and even a fourth tier
8、 of arcades. Last tier of arcades send straight arteries to each side of small intestine.,Jejunum,ileum,Vasa recta,Veins of small intestine unite to form superior mesenteric v. and then join splenic v. to form hepatic portal v. posterior to neck of pancreas.,Jejunum and ileum,II. 盲肠和阑尾 Cecum and ver
9、miform appendix I)盲肠 Cecum is blind sac, first part of large intestine,with largest diameter and thinnest wall, usually lying in right iliac fossa, rarely in lesser pelvis or at a higher level, even to right colic flexure. It is about 68 cm in length and width. Superiorly, it joins ascending colon.,
10、Cecum is an intraperitoneal organ, almost surrounded by peritoneum. It is relatively mobile, and sometimes cecum have a short mesocolon, cecum becomes more mobile, called “mobile cecum”, and easily to herniate or volvulate.,Terminal ileum opens into medial and posterior aspect of cecum, and is partl
11、y invaginated into cecum to form folds above and below opening, called Ileocecal valve (回盲瓣). It takes part in preventing,reflux of cecal contents into ileum, and controlling speed of,elimination of ileal contents into colon., I)阑尾 Vermiform appendix is a narrow, blind worm-like tube, usually 68 cm
12、in length, 0.5cm in diameter, but extremes varying from 220 cm have been recorded. It opens into posteromedial aspect of cecum about 2 cm,below ileoceal valve ( orifice). Base of appendix lies at point of convergence of three colic bands (used as a guide to find appendix during operation).,Surface m
13、arking of base is at the so-called McBurneys point which is at junction of lateral and middle thirds of line joining right anterior superior iliac spine and umbilicus. This point represents,a fixed point on abdominal wall, it is area of greatest tenderness in appendicitis. Special position is rarely
14、 as high position appendix (under liver), extraperitoneal appendix, and left lower abdominal position appendix.,Appendix is entirely covered by peritoneum and has a triangular mesentery (阑尾系膜 Mesoappendix) which extends from terminal part of ileum to appendix. Tip of appendix is very variable in pos
15、ition, according to statistical data of Chinese people, frequently it lies at following position: Preileal position (in 28%), Pelvic,position (in 26%), Retrocecal position (in 24%), Retroileal position (in 8%), Subcecal position (in 6%).,Appendicular artery arises from ileocolic a. Most of appendicu
16、lar arteries are single (in 92%). It runs in free margin of meseoappendix then along wall of appendix.,Appendicular vein drains into hepatic portal vein via superior mesenteric veins. In clinic, when appendix becomes suppurative appendicitis, bacterial emboli may enter liver and hepatic,abscess. Dur
17、ing appendicectomy, do not extrude inflamed appendix to prevent infective emboli from entering into blood flow.,III.结肠 Colon I) Features of colon 1.结肠带 Colic bands There are three band-like longitudinal colic bands on wall of cecum and colon.,They converge at base of vermiform appendix and become co
18、ntinuous with its outer layer of muscle.,2.结肠袋 Haustra of colon Because lengths of colic bands are shorter than that large intestine, large intestine is typically sacculated, forming haustra of colon. 3.肠脂垂 Epiploic appendices They are small projecting,pouches of peritoneum filled with fat, and are
19、numerous on transverse and sigmoid colons, but are absent on cecum, appendix & rectum., II) Subdivisions of colon Colon includes ascending, transverse, descending and sigmoid colons. 1.升结肠 Ascending colon is about 15 cm in length. It is,continuous inferiorly with cecum and extends upwards to undersu
20、rface of right lobe of liver, where it bends sharply forwards and to left to form right colic flexure (结肠右曲), and is continuous with transverse colon.,2.横结肠 Transverse colon is about 50 cm in length, and is the most mobile part of colon. It extends across abdomen from right colic flexure to left col
21、ic flexure where it continues descending colon.,3.降结肠 Descending colon descends almost vertically from left colic flexure to sigmoid colon at left iliac crest. 4.乙状结肠 Sigmoid colon extends from descending colon to rectum at level of S3., III) Blood vessels of colon 1. Arteries Blood supply of colon
22、is in part through branches of superior mesenteric a., and in part through those of inferior mesenteric a,Right half of colon is supplied by branches of sup. mesenteric a Left half of colon is supplied by branches of inf. mesenteric a,Vessels from two sources usually meet at approximately left colic
23、 flexure. From ileocecum to terminal part of,sigmoid colon, an arterial arcade formed by anastomosis of colic branches of superior and inferior mesenteric arteries, is called colic marginal artery (结肠缘动脉) which gives longer and shorter branches to enter intestinal wall vertically.,2. Veins Venous dr
24、ainage of colon corresponds largely to its arterial supply.,Veins of ascending and transverse colons drain largely into superior mesenteric vein, and veins of descending and sigmoid colons into inferior mesenteric vein. The latter empties commonly into splenic vein.,IV. 肝门静脉 Hepatic portal vein I)特点
25、 Features It is a short venous trunk, about 68 cm in length and 11.2 cm in diameter Formed behind neck of pancreas by union of superior mesenteric v. and splenic v. Ascends upwards and posterior to first part,of duodenum and then enters hepatoduodenal lig. behind common bile duct and proper hepatic
26、a. to porta hepatis Divides right & left b. into left & right lobe of liver.,It is functional blood vessel of liver Drains blood from digestive tract from lower end of oesophagus to upper end of anal canal, pancreas, gall bladder, bile ducts and spleen. Hepatic portal v. is a venous trunk between tw
27、o sets of capillaries: one set is capillaries of alimentary canal; other is sinusoid of liver There are no functioning valves in hepatic portal system When pressure in hepatic portal v. ascends, blood can flow adversely., II)属支 Tributaries Hepatic portal v. have 7 tributaries: 1.肠系膜上静脉 superior mese
28、nteric v., 2.脾静脉 splenic v., 3.肠系膜下静脉 inferior mesenteric v., 4.胃,左静脉 left gastric v., 5.胃右静脉 right gastric v., 6.胆囊静脉 cystic v., 7.附脐静脉 paraumbilical v All tributaries except cystic and paraumbilical, accompany their corresponding arteries, and drain venous blood from territory of arteries., III)门腔
29、静脉系之间的吻合 Portal-Systemic Anastomoses Veins between hepatic portal and systemic veins, there are many collateral anastomoses. Normally, these anastomoses are unopened. In portal hypertension, some factors increase venous pressure in portal system, some of portal drainage may then back up and pass thr
30、ough portal-systemic anastomoses in a reverse direction into systemic veins.,Four important areas of portal-systemic anastomoses occur: 1. At lower end of oesophagus,Hepatic portal v. left gastric v. esophageal venous plexus esophageal v. azygos v. superior vena cava 2.At rectal venous plexus Hepati
31、c portal v. splenic v. inferior mesenteric v. superior rectal v. rectal venous plexus inferior rectal and anal v. internal iliac v. common iliac v. inferior vena cava, 3. At periumbilical venous plexus Hepatic portal v. paraumbilical v. periumbilical venous plexus following routes: thoracoepigastric
32、 v. lateral thoracic v axillary v subclavian v brachiocephalic v superior vena cava; superior epigastric v. internal thoracic v. brachiocephalic v. superiorvena cava; superficial epigastric v. great saphenous v. femoral v. external iliac v. common iliac v. inferior vena cava; inferior epigastric v.
33、external iliac v. common iliac v. inferior vena cava., 4. Portal-retroperitoneal anastomosis anastomoses through unions between small veins At posterior wall of abdomen, small tributaries of sup. and inf. mesenteric v. anastomose with small branches of inferior diaphragm v., renal v. and testicular
34、v.; anastomoses through vertebral venous plexus At posterior wall of abdomen, small tributaries of sup. & inf. mesenteric and splenic v. are anastomosed with small tributaries of posterior intercostal v., vertebral v. and lumbar v,Clinical Notes: Hepatic portal hypertension Normally, hepatic portal
35、venous blood traverses liver and empties into inferior vena cava. This pathway may be obstructed by various causes, e. g. , pressure of a tumor on hepatic portal v., cirrhosis of liver, valvular disease of heart.,In this condition, portal venous pressure rises and collateral pathways open up between
36、 portal and cava venous systems.,Anastomotic veins then become dilated and varicose and they may even rupture to lead to a fatal hematemesis. The varicose veins are called esophageal varices in esophagus, hemorrhoids in rectum, and caput medusae around umbilicus., Portal Hypertension for Surgeons 1.
37、Total Shunts Common way of reducing portal pressure is to divert blood from portal venous system to systemic venous system by creating a communication between portal vein and inferior vena cava.,When hepatic portal vein and inferior vena cava cross each other at angles, end-to-side portal-caval anas
38、tomosis is suitable. When hepatic portal v. runs parallel to inferior vena cava, side-to-side portal-caval anastomosis is desirable.,Side to Side Portocaval,End to Side Portocaval, Portal Hypertension for Surgeons 1.Total Shunts Because splenic vein and left renal vein lie close to each other, anoth
39、er way is to join splenic vein to left renal vein (splenorenal anastomosis) after removal of spleen (splenectomy).,Central Splenorenal Shunt,Distal Splenorenal Shunt, Portal Hypertension for Surgeons 2.Transjugular Intrahepatic Portocaval Shunt (TIPS 经颈静脉肝内门体静脉内支架分流术), Portal Hypertension for Surgeo
40、ns 2.Transjugular Intrahepatic Portocaval Shunt (TIPS 经颈静脉肝内门体静脉内支架分流术), Portal Hypertension for Surgeons 3. Endoscopic Banding 经内镜食管曲张静脉套扎术, Portal Hypertension for Surgeons 4. Name Tube (三腔两囊管止血),Sengstaken-Blakemore Tube,Minnesota Tube,Section 7 腹膜后间隙 Retroperitoneal space,I.概述 Introduction I) Po
41、sition It lies between parietal peritoneum and transvers fascia of posterior abdominal wall, from diaphragm to promontory of sacrum, continuation with extraperitoneal fascia. Inflammation in retroperitoneal space may spread superiorly and inferiorly., II) Contents Important contents in retroperitone
42、al space are kidneys, suprarenal glands, abdominal part of ureters, abdominal aorta, inferior vena cava, nervers and lymphatics, loose connective tissue. Pancreas and duodenum have been described in supracolic compartment.,II. Main Contents I)肾 Kidney 1.位置 Position Kidneys lie on posterior abdominal
43、 wall, one on each side of vertebral column. Upper poles are closer to one another than lower poles.,Left kidney lies at level from lower border of T11 to L2; 12th rib is behind its middle part of post surface. Right kidney lies at level from upper border of T12 to L3; 12th rib crosses its upper par
44、t of post surface.,Renal hilum(肾门) is at level of spine of 1st lumbar vertebra, and 5 cm lateral to it, or at angle where lateral border of erector spinae crosses 12th rib (called Renal angle肾角 or Renal region ). Tenderness or percussing pain caused by kidney disease is localized to this renal angle
45、.,2.毗邻 Relation Upper pole of kidney is covered by suprarenal gland.,Posteriorly Each kidney lies on four muscles (Diaphragm and pleural cavity, Psoas major, Quadratus lumborum and transversus abdominis) and three nerves (Subcostal, Iliohypogastric, Ilioinguinal nerve). Medial Left kidneyabdominal a
46、orta; Right kidneyinferior ceva vana.,Anteriorly Left kidney is in contact with Stomach and Spleen (superior), Tail of pancreas (middle), and Coils of jejunum Right kidney is in contact with Right lobe of liver (superior), Descending part of duodenum (middle), and Right colic flexure (inferiorly).,S
47、tructures which enter and leave renal hilum is called Renal pedicle, including renal vein, renal artery, renal pelvis, lymphatic vessels and nerves.,Order of structures in renal pedicle from anterior to posteriorV. A. P.; from superior to inferiorA. V. P.,3.肾门、肾窦、肾蒂 Renal hilum, Sinus and Pedicle Me
48、dial border of kidney is concave and has a vertical slit called Renal hilum. Renal sinus is renal hilum leads into a space within kidney. It is occupied by renal vessels, minor and major renal calices, renal pelvis and some adipose tissue.,4.被膜 Coverings Each kidney is enclosed, from outside inwards
49、, by renal fascia, adipose capsule and fibrous capsule. 肾筋膜 Renal fascia As a separate sheath on outside, surrounds both kidney and suprarenal gland, holding organs in place.,Because ureter leaves, ant. & post. layers of Renal fascia are open below kidney.,脂肪囊 Fatty renal capsule A thick adipose connective tissue between renal fascia and fibrous capsule, surrounds kidney. It acts as a shock absorber to protect kidney from jolt