Abdominal “Viscera” I) Scrotum A) Arteries: 1) Posterior scrotal arteries – terminal branches of internal pudendal.  2) Anterior scrotal arteries – terminal branches of external pubendal branches of femoral artery. B) Veins: follow arteries             C) Lymphatics: drain into the superficial inguinal lymph nodes D) Nerves: 1) Genital branch of the genitofemoral nerve (L1,2) supply the anterolateral surface of the scrotum.                                2) Anterior scrotal nerves- branches of the ilioinguinal nerve (L1), supplying the anterior surface of the scrotum.                                3)Posterior scrotal nerves – branches of the perineal branch of the pudendal nerve (S2-4) supplying the posterior surface of scrotum.        4) Perineal brances of the posterior femoral cutaneous nerve (S2,3) supplying the lateral surface of the scrotum.   II) Testes             A) Arteries: The testicular arteries arise from the abdominal aorta just inferior to the renal arteries.             B) Veins: the testicular veins emerge from the testis and epididymis and join to form a venous network, the pampiniform plexus.  The cooler venous bood within the pampinoform plexus absorbs heat from the arterial blood, providing a thermoregulatory system for the testis.  The L testicular vein empties into the L renal vein.  The R enters the IVC.             C) Lymphatics: drainage is to the lumbar and pre-aortic lymph nodes.             D) Nerves: The autonomic nerves of the testis arise as the testicular plexus of nerves on the testicular artery, which contains vagal parasymp fibers and sympathy visceral afferent fibers from T7.   III) Hernies             A) Indirect: leaves the abdominal cavity lateral to the inferior epigastric vessels and enters the deep inguinal ring.  Passes through the inguinal canal.  Has a hernial sac formed by the persistent processesus vaginalis.  Exits the superficial inguinal ring and commonly enters the scrotum.             B) Direct: Leaves the abdominal cavity medial to the inferior epigastric artery, protruding through an area of relative weakness in the posterior wall of the inguinal canal.  Has a hernial sac formed by tranversalis fascia.  Does not traverse the entire inguinal canal.  Emerges through or around the conjoint tendon to reach the superficial inguinal ring, gaining an outer covering of external spermatic fascia, inside or parallel to that on the cord itself.  Lies outside the processes vaginalis, which is usually obliterated.  Almost never enters the scrotum.   IV) Mesentary: a double layer of peritoneum reflecting away from the abdominal wall to enclose part or all of one of the viscera.  A mesentery constitutes a continuity of the visceral and parietal peritoneum that provides a means for neurovascular communication between the organ and the body wall.  V) Oemntum: a broad, double layered sheet of peritoneum passing from the stomach to another abdominal organ.  The greater omentum (gastrocolic ligament) hangs down from the greater curvature and proximal part of duod.  After descending, it folds back and attaches to the anterior surface of the transverse colon.  The lesser omentum (gastrohepatic and gastroduod ligaments) connects the lesser curvature and proximal part of duod to the liver.   VI) Esophagus:             A) retroperitoneal             B) Arteries: supply of the abdominal part of the esophagus is from the left gastric artery, branch of ciliac trunk, and the left inferior phrenic artery.              C) Veins: left gastric veins à portal vein.  Thoracic portion of esoph drains through esophageal veins to azyos veins.             D) lymph: left gastric nodes à ciliac nodes             E) nerves: vagal trunks à anterior and posterioar gastric nerves                              And thoracic symp trunks à greater and lesser splanchnic nerves                              And esophageal plexus   VII) Stomach:             A) Arteries: Left gastric artery, arises directly from the ciliac trunk and runs in the lesser omentum to the carida of the stomach.  It gives off the esophageal artery and then turns abruptly to course along the lesser curvature and anastomose with R gastric.  R gastric arises from the hepatic artery and runs to the left only lesser curvature.  R gastro-omental artery arises as one of two terminal branches of the gastroduodenal artery, runs to the left along the greater curvature.  L gastroomental artery arises from the distal part of the splenic artery and courses along greater curvature.  Short gastrics also arise from the distal part of the splenic artery and pass to the fundus of the stomach.             B) Veins: the L and R gastric veins drain directly into the portal vein while the short gastric veins and the L gastro-omental vein drain into the splenic vein, which then joins the superior mesenteric vein to form the portal vein.  The R gastro-omental vein usually empties into the SMV.             C) Lymph: accompany the arteries along the greater and lesser curvatures and drain where the gastric and gastro-omental lymph nodes are.             D) Nerves: the parasym nerve supply of the stomach is from the anterior and posterior vagal trunks and their branches, which enter the abdomen through the esophageal hiatus.  The symp nerve supply from T6-T9 passes to the celiac plexus via greater splanchnic nerves and is distributed as plexuses around the gastric and gastro-omental arteries.   VIII) Duodenum:             A) Arteries: Proximally (parts 1 and 2) supplies by celiac trunk à gastroduod à superior pancreaticoduodenal artery.  Distally supplied by SMA à inferior pancreaticoduodenal artery.  These form a loop and are a site of collateral circulation.             B) Veins: The duodenal veins follow the arteries and drain into the portal vein             C) Nerves: Derive from vagus and sympathetic nerves thorugh the celiac and superior mesenteric plexuses on the pancreaticoduodenal arteries.  IX) Jejunum and Ileum:             Arteries: SMA à arterial arcades à vasa recta             Veins: SMV à splenic vein à portal vein             Nerves: The SMA and its branches are surrounded by a dense perivascular nerve plexus though which the nerve fibers are conducted to the parts of the intestine supplied by the SMA.  The symp fibers in the nerves arise from T5-9 and reach the celiac plexus thorugh the symp trunks and thoracic (greater and lesser) splanchnic nerves.  The presymp symp fibers synapse on cell bodies of postsyn symp neurons in the celiac and superior mesenteric (prevertebral) ganglia.  The para fibers in the nerves to the jejunum and ileum derive from the posterior vagal trunk.  The presym para fibers synapse with postsynaptic para neurons in the myenteric and submucosous plexuses in the intestinal wall.  Sypmathetic stimulation reduces motility of the intestine and secretion and acts as a vasoconstrictor.  Parasympathetic stimulation increases motility of the intestine and secretion, restoring digestive activity following a symp reaction.    X) Large intestines:  Large can be distinguished from small by teniae coli (three thickened bands of longitudinal muscle fibers) haustra (sacculations or pouches of the colon between the teniae) omental appendices (fatty appendices of the colon) and caliber (the internal diameter is much larger).  Ascending and descending colon are retroperitoneal.  The transverse and sigmoid colon are intraperitoneal, and is covered by transverse and sigmoid mesocolon.             Arteries: the cecum is supplied by the ileocolic artery, the terminal branch of the SMA.  The appendix is supplied by the appendicular artery, a branch of the ileocolic artery.  The arterial supply to the ascending colon and right colic flexure is from the branches of the SMA- the ileocolic and right colic.   The arterial supply of the transverse colon is mainly from the middle colic artery.  Distal to the left colic flexure, blood is supplied by the IMA à left colic and sigmoid arteries.  Usually the branches of the arteries supplying the colon anastomose thus forming a continuous channel, marginal artery, and a potential opportunity for collateral circulation.             Veins: A tributary of the SMV, the iliocolic vein, drains blood from the cecum and appendix.  Tribuataries of the SMV, the ileocolic and right colic veins, drain blood from the ascending colon.  Venous drainage of the transverse colon is through the SMV.  The IMV returns blood from the sigmoid and descending colon, flowing into the splenic vein and then the portal vein on its way to the liver.              Nerves: The nerve supply to the cecum and appendix derives from sympathetic and parasympathetic nerves from the superior mesenteric plexus.  The sympathetic nerve fibers originate in the lower thoracic part of the spinal cord, and the parasym nerve fibers derive from the vagus.  Afferent nerve fibers from the appendix accompany the symp nerves to T10.  The nerves to the ascending colon derive from the superior mesenteric plexus.  The nerves of the transverse colon arise from the superior mesenteric plexus and follow the right and middle colic arteries.  These nerves transmit symp and para (vagal) nerve fibers.  The nerves that derive from the inferior mesenteric plexus follow the left colic artery.  The sympathetic nerve supply of the descending and sigmoid colon is from the lumbar part of the symp trunk and the superior hypogastric plexus thorugh the plexuses on the IMA and its branches.  The parasym nerve supply is from the pelvic splanchnics, which convey presympathetic fibers from the sacrum.  XI) Spleen:             Arteries: celiac trunk à splenic artery             Veins: splenic vein is formed by tributaries emerging from the hilum.  It is joined by the IMV and runs posterior to the body and tail of the pancreas throughout most of its course.  The splenic vein unites with the SMV posterior to the neck of the pancreas to form the portal vein.              Nerves: derived from the celiac plexus and are vasomotor in function.   XII) Pancreas: Lies retroperitoneally and transversely across the posterior abdominal wall, posterior to the stomach between the duod on the right and the spleen on the left.  The pancreas produces exocrine secretion (pancreatic juice from the acinar cells) that enters the duod and endocrine secretions (glucogon and insulin from the islet cells) that enters the blood.  The pancreatic duct begins in the tail, runs to the head and then merges with the bile duct.  They unite to form a short, dilated hepatopancreatic ampulla which opens into the descending part of the duod.             Arteries: derive mainly from the branches of the splenic artery.  The anterior and posterior superior pancreaticoduodenal arteries, branches of the gastroduodenal artery, and the anterior and posterior inferior pancreaticoduodenal arteries, branches of the SMA, supply the head.              Veins: The pancreatic veins are tributaries of the splenic and superior mesenteric parts of the portal vein; however, most of them empty into the splenic vein.              Nerves: Derived from vagus and thoracic splanchnic nerves passing thorugh the diaphragm.  The parasym and symp fibers reach the pancreas by passing along the arteries from the celiac plexus and superior mesenteric plexuses.  They are vasomotor (symp) and paenchymal (sym and para – to acinar and islet cells) in their distribution.    XIII) Liver: Part of the lesser omentum is  the hepatoduodenal ligament which encloses the portal triad (portal vein, hepatic artery and bile duct; a few lymph nodes and lymphatic vessels and the hepatic plexus of nerves also.)  The L lobe is demarcated from the caudsate and quadrate lobes by the fissure for the round ligament of the liver and the fissure for the ligamentum venosum on the visceral surface and by the attachment of the falciform ligament on the diaphragmatic surface.  The round ligament (ligamentum teres) is the obliterated remains of the umbilical vein, which carried well oxygenated blood from the placenta to the fetus.  The ligamentum venosum is the fibrous remnant of the fetal ductus venosus that shunted blood from the umbilican vein toe ht IVC, short circulating the liver.             The liver recies bllod from two sources: The portal vein (70%) and the hepatic artery (30%).  These two run together in the segments of the lobes are are drained by hepatic veins.  The liver is a major lymph producing organ.             Arteries:  The hepatic artery, a branch of the ciliac trunk, carries well O2 blood from the aorta.  Subdivides into R and L branches.             Veins: The portal vein carries poorly O2 blood from the abdominopelvic portion of the GI tract.  Subdivides into R and L branches.  The hepatic veins, formed by the union of the central veins of the liver, open into the IVC just inferior to the diaphragm.              Nerves: the nerves of the liver derive from the hepatic nerve plexus, the largest derivative of the celiac plexus.  It consists of symp fibers from the celiac plexus and para fibers from the anterior and posterior vagal trunks.    XIV) Bile Duct:  R and L hepatic ducts à porta hepatis à coomon hepatic duct which is joined by the cystic duct to form the bile duct. à the bile duct is later met by the pancreatic duct and the two run obliquely thorugh the wall of the duod where they unite to form the hepatopancreatic ampulla.  When food enters the duod, the gall bladder sends concentrated bile through the cystic and bile ducts to the duod.              Arteries: posterior superior pancreaticoduod artery and gastroduodenal artery supply the retropertitoneal part of the bile duct.  The cystic artery supplied the proximal part of the duct.  The right hepatic artery supply the middle part of the duct.             Veins: The veins from the proximal part of the bile duct and the hepatic ducts enter the liver directly.  The posterior/superior pancreaticoduod vein drains the distal part of the bile duct and empties into the portal vein.             Nerves: Nerves are prominent along the bile duct.  The posterior hepatic plexus is related to the bile duct and its nerves arise in the right celiac plexus and from the celiac division of the posterior vagal trunk.   XV) Gallbladder:             Arteries: the cystic artery supplies the gallbladder and cystic duct commonly arises from the right hepatic artery in the angle between the common hepatic duct and the cystic duct.              Veins: the cystic veins drain directly into liver or thru portal veins.             Nerves: the nerves to the gallbladder and cystic duct pass along the celiac plexus (symp), the vagus nerve (para) and the right phrenic nerve (sensory).   XVI) Kidneys: There retroperitoneal organs remove excess water, salts, and wastes of protein metabolism from the blood while returning nutrients and chemicals to the blood.  The kidnes convey the waste products from the blood into urine, which drains thorugh the ureters to the urinary bladder.  The ureters pass over the bifurcation of the colon iliac arteries.  They then run along the lateral wall of the pelvis and enter the urinary bladder.  The ureters are muscular ducts with narrow lamina.             Minor calices à major calixes à renal pelvis à ureters.             Each minor calys is indented by the apex of the renal pyramid – the renal papilla.              Above each kidney are the suprarenal glands: The triangular right gland and the semilunar left gland.  Each has two parts; the suprarenal cortex and medulla, each with different origins, functions.             Arteries:  The renal arteries arise from the aorta at L1-2, and each divides at the hilum into five segmental arteries that do not anastomose.  The longer R renal artery passes posterior to the IVC.  The arteries to the ureters arise from the renal artery, testicular or ovarian artery, and the abdominal aorta.  The suprarenal arteries are the superior (from inferior phrenic) middle (from abdominal aorta near SMA) and inferior (from renal) suprarenal arteries.             Veins: the renal veins lie anterior to the renal arteries and the longer left renal vein passes anterior to the aorta.  Each renal vein drains into the IVC.  The veins of the ureters drain into the renal and testicular or ovarian veins.  The venous drainage of the suprarenal glands is a large suprarenal vein.  The R one drains into the Ivc.  The longer L one is often joined by the inferior phrenic vein, and empties into the left renal vein.             Nerves:  The nerves to the kidneys and ureters arise from the renal plexus and consist of symp, para and visceral afferent fibers.  The renal plexus is supplied by fibers fro the thoracic (esp. least) splanchnic nerves.  The suprarenal glands are innervated by the celiac plexus and thoracic splanchnics.  The nerves are mainly myelinated presymp sympathetic fibers that derive from the lateral horn of the spinal cord and are distributed to the chromoffin cells in the suprarenal medulla.   XVII) Diaphragm:             Arteries: The arteries supplying the superior surface of the diaphragm are the pericardiacophrenic and musculaophrenic arteries, branches of the internal thoracic, and the superior phrenic arteries, arising from thoracic aorta.  The arteries supplying the inferior surface of the diaphragm are the inferior phrenic arteries, which are typically the first branches of the abdominal aorta.             Veins: superiorly – pericardiacohrenic and musculophrenic veins à internal thoracic veins AND superior phrenic vein à IVC. Inferiorly – R inferior phrenic vein à IVC.  L (2 branches) à IVC and posterior branch joining the left suprarenal vein.             Nerves: The entire motor supply to the diaphragm is from the phrenic nerves (C3-5).  The phrenic nerves also supply fibers for pain and proprioception.  Peripheral parts of the diaphragm receive their sensory nerve fibers from the intercostal nerves (T5-11) and the subcostal nerves (T12).