Stomach and Spleen Flashcards
Location and shape of stomach
Upper abdomen, left of liver Intraperitoneal organ J shaped Lesser curvature, in epigastric region Greater curvature in hyperchondriac
Location and shape can vary on muscular contraction
Hypertonic
Hypotonic
Atonic
Location and shape can vary on body shape
Ectomorph
Mesomorph
Endomorph (steerhorn)
Parts of the stomach
Fundus, storage, filled with gas
Cardia, has columnar epithelial for mucus secretion
Body, storage, mucus, HCL, pepsinogen, intrinsic factor secretion
Pyloric antrum, mixing/grinding, gastrin
Functions of the stomach
Temporary chyme store for 4hrs
Secretions, gastrin enhances intestinal motility
Intrinsic factor, precursor for B12
Mucus, protects oesophagus and stomach from acid
Breakdown of food, churning
Pepsin, hydrolyse proteins
HCL, allows pepsin action, bacteria destruction
Absorption of H20, electrolytes, alcohol, aspirin
Arrangement of gut wall
Mucosal layer
Submucosal layer
Muscular externa
Adventitia/serosa
Function of structures in mucosal layer
Epithelium absorbs Glands secrete mucus Ducts come from pancreas, liver Lymphoid tissue removes pathogens Muscular mucosa, muscular movement in lumen
Function of structures in submucosal layers
Nerve cells, blood vessels, cell bodies here form ENS, function independently in Meissner’s plexus
Control contractions of muscular mucosa, self controlling
Function of structure in muscular externa
Outer longitudinal, inner circular muscle for peristalsis
Myenteric (Auerbach) plexus, part of ENS
Stomach has additional inner oblique layer
Function of structure of adventitia/serosa
Serosa, peritoneal membrane that wraps around the gut
If retroperitoneal, covered in adventitia
Blood vessels and nerves that come from outside, joint gut wall here
Motility of gut due to vagus nerve stimulation by parasympathetic innervation in proximal part of gut
Structure of stomach wall
Longitudinal muscle
Circular muscle
Oblique muscle, mucosa of longitudinal folds (rugae), allows room for expansion
Relations of the stomach
R kidney behind duodenum
IVC, A behind pyloric antrum
L kidney and pancreas behind body
DJ flexure behind bottom of greater curvature
Function of coeliac trunk
Comes from aorta, supplies liver, spleen, stomach
Branches into L gastric, splenic, common hepatic
Vasculature of stomach (veins)
Whole of gut drains into hepatic portal vein into liver
If hepatic systems blocked, blood enters azygos system around oesophagus => SVC
Splenic vein
L and R gastricepiploic (greater curvature)
Gastric vein (lesser curvature)
Vasculature of the stomach (arteries)
L and R gastricepiploic (greater curvature)
From the coeliac trunk:
L gastric artery
Splenic
Common hepatic
Gastroduodenal artery
Superior pancreatic duodenal
Lymphatics of stomach
Pancreasticolienal R gastroomental Pyloric R and L gastric Coeliac
All foregut nodes pass into coeliac nodes (preaortic lymph nodes)
Others go to paraaortic nodes (kidney etc)
Nerve supply of the stomach
Parasympathetic nerves
Motor and secretomotor
L vagus => anterior vagal trunk
R vagus => posterior vagal trunk
Nerve supply of the stomach
Sympathetic nerves
Afferent, epigastric pain
Efferent, vasoconstriction and antperistaltic
Splanchic nerves from coeliac ganglia cells form esophageal plexus
Spleen
Largest lymph organ
Highly vascular
Covered by peritoneum, intraperitaneal
At an angle, posterior, rib 10, comes forward to mid auxiliary vein
Functions of the spleen
Removes blood borne antigens
Removes and destroys old/damaged blood cells
Stores RBCs and platelets
Haemopoiesis in fetus
Structure of a spleen
Upper pole Diaphragmatic surface Indentation of anterior border Lower pole Visceral surface Hilium (point of insertion for splenic artery and vein
Has gastric, renal and colic and pancreatic sections
Causes of an enlarged spleen
Liver disease Blood cancers (lymphoma, leukemia, myelofibrosis) Infection Abnormal blood flow and congestion Catcher disease Blood cell disorders inflammatory disease
