Abdominal Cavity: Peritoneum & GIT

(G, To stretch or cover around ) Peritoneum A serous membrane of 2 continuous layers that covering the abdominal organs (G, To stretch or cover around ) Parietal: lining internal abdominal wall Visceral: lining abdominal organs (viscera) Peritoneal cavity: space between parietal & visceral layers fluid filled  reduce friction * NO organs in peritoneal cavity

Abdominal Organs Relation to Peritoneum Intraperitoneal: completely covered by visceral peritoneum Retroperitoneal: posterior (behind) the peritoneum touched anteriorly by parietal peritoneum

Peritoneal Cavity 2 parts Greater sac: main part of peritoneal cavity Lesser sac (omental bursa): extensional cavity behind the stomach allows free movement of stomach connects with greater sac through epiploic foramen

Epiploic Foramen Foramen of Winslow Connects lesser sac to greater sac Boundaries: Ant.: portal triad (p. vein, h.a., & bile duct) Post.: IVC Sup.: Liver (caudate lobe) Inf.: duodenum (1st part)

Foramen of Winslow & Lesser Sac

Terms describing parts of peritoneum Peritoneum has special names at specific regions: omentum mesentry & mesocolon ligaments

Greater curvature of stomach Omentum Broad, double layered sheet of peritoneum that connects stomach to another abdominal organ 2 parts 1. Greater Omentum: Greater curvature of stomach  Down (like apron) Reflects up again Ant. transverse colon

Lesser curvature of stomach & small part of dudenum (2cm) 2. Lesser Omentum Lesser curvature of stomach & small part of dudenum (2cm)  Liver Post. to it = lesser sac * The free edge of lesser omentum is called: hepatoduodenal ligament  contains portal triad

Hepatoduodenal Ligament

Mesentery & Mesocolon Mesentry: Mesocolon: double layer of peritoneum connects small intestine to posterior abdominal wall mesentry of small intestine Mesocolon: double layer of peritoneum connects large transverse mesocolon sigmoid mesocolon mesoappendix

Mesentery & Mesocolon

Ligaments Double layer of peritoneum that usually attached to the liver Falciform Lig.: Attachs the liver to ant. abdominal wall & ends by enclosing ligamentum teres Hepatoduodenal Lig.: The free edge of …? 1st 2 cm of duodenum to liver Contents?

Peritoneal Nerve Supply Parietal Peritoneum: (sensations) T7 – T12 L1 (iliohypogastric) Obturator nerve (in the pelvis) Visceral Peritoneum: Autonomic nerve supply (only for stretch)

Organs Relations to Peritoneum Stomach (intra) Duodenum (retro, except 1st 2 cm) Jejunum & ileum (intra) Cecum (??) Appendix (intra) Ascending (retro) Transverse (intra) Descending (retro) Sigmoid (intra) Rectum: within the pelvis upper part (ant. & lat.) middle part (ant.) lower (no covering, subpertoneal) Liver: Intraperitoneal except over 3 areas Pancreas: Retroperitoneal except for the tail Spleen: Kidneys:

Gastro-Intestinal Tract (GIT) in Abdomen Esophagus (abdominal part, 1.25cm) Stomach Small intestine Large intestine

Esophagus Enters through esophageal opening (T10) Pass about 1.25cm before entering stomach Ends at cardiac orifice (T11)

Stomach (Read your text for detailed anatomy) *Intraperitoneal 4 regions Cardia: surrounds esophag. opening Fundus most sup. Part (dome shape) Body central part, largest Pylorus (gate guard) antrum & canal

Stomach 2 openings: Cardiac orifice esophagus  stomach (Physiologic sphincter) Pyloric sphincter stomach  duodenum (Anatomic & Physiologic) Anat = thickened circular m. layer 2 curves: greater (lf.) & lesser (Rt.)

Stomach

Muscular Wall of Stomach Outer ?? Middle ?? inner ?? ???

Small Intestine (Read your text for detailed anatomy) Duodenum (C-shaped) Jejunum Ileum

Duodenum * Retroperitoneal except over omental attachment (first 2 cm) 4 parts 1. Superior (1st): From pylorus Horizontal (vertebral level?) 2. Descending (2nd): Rt. To L2 & L3 Curves around head of pancreas Receives bile & main pancreatic ducts (Major papilla)

Duodenum

Ampulla of Vater & Major duodenal papilla

3. Horizontal (3rd): Ant. to IVC At level of L3 4. Ascending (4th): At left side of L3 Ends at duodenojejunal jxn. Forms flexure (bending) (flexure = lig. of treitz) Small intestine enters peritoneum at the lig. of treitz

Jejunum & Ileum * Intraperitoneal Jejunum: (L, empty) upper left half Ileum: (G, twisted) lower right half ends at ileocecal junction (valve)

Large Intestine (Read your text for detailed anatomy) Cecum & Appendix Ascending (retro) Transverse (intra) Descending (retro) Sigmoid (intra) Rectum (in pelvic cavity)

Distinguishing Features of Large Intestine Haustra (saccules): Sacculations or pouches of the colon Teniae coli: 3 longitudinal bands of muscle that extend from the base of the ?? until the rectum Epiploic (omental) appendices Fatty tags attached to the wall of the colon Rt. & Lf. Colic Flexures

Clinical Notes

Peritonitis: inflammation of peritoneum that causes pain in abdomen & overlying skin. Usually associated with Ascites: distention of peritoneal cavity by abnormal fluid Rx: draining the cavity fluids (paracentesis) by inserting a needle into peri. Cavity, usually through linea alba

Peptic Ulcer Disease A discontinuation (erosion) in the mucosal covering in an area of the GIT (esophaguslarge intestine). Most commonly in the ? Causes: 1. Bacteria: Helicobacter pylori ~80% PUD urease  urea= ammonia + CO2 2. Drugs & Irritants: NSAIDs (aspirin), smoking, alcohol 3. Hypersecretion of HCl

Rx.: antibiotics: only when ?? Amoxi. + Mitro. + Clarithromycin gastric acid inhibitors: histamine receptor (H2) blockers or PPI Antacids: buffer Diet: irritants Surgical: Vagotomy, antrum removal (out of date) Complications: GI-bleeding: - erosion of a bld. Vessel - hematemesis (?) Perforation: - erosion of the whole wall  opening into abd. Cavity  peritonitis & inflammation of adjacent organs * requires emergency surgical treatment

Inflammation of the appendix due to: Appendicitis Inflammation of the appendix due to: 1. Bact. Infection or 2. luminal obstruction: by chyme or foreign objects Signs & Symptoms: 1. Pain: Starts: vague pain in peri?? region (referred pain) Later: sever pain in  Rt. Quadrant due to irritation of ?? 2. Vomiting, 3. Fever, 4. Leukocytosis Complications: perforation of the appendix  peritonitis & gangrene necrosis

McBurney’s Point On a straight line : 1/3 from ant. sup. iliac spine 2/3 from the umbilicus Corresponds to the base of the appendix The incision site during appendectomy (removal of the appendix)

Diarrhea & Constipation  In frequency, volume & fluid content of the feces Because of:  motility &  absorption of the intestine Complication: Dehydration & electrolyte imbalance Rx.: ? Constipation Infrequent & difficult defecation Because of:  motility & absorption of the intestine Rx.: - mild laxative: castor oil or Mg(OH)2 - fibers diet & exercise