Theme 1: Lecture 3 - Contents of the abdomen Flashcards
What are the 4 quadrants that the abdomen can be divided into
- Right upper quadrant
- Left upper quadrant
- Right lower quadrant
- Left lower quadrant
What are the 9 regions that the abdomen can be divided into
-Right hypochondriac region
-Right lumber region
-Right inguinal (iliac) region
-Epigastric region
-Umbilical region
-Hypogastric (pubic) region
-Left hypochondriac region
-Left lumber region
Left inguinal (iliac) region
Through which lines is the abdomen divided into 9 regions
- The mid clavicular lines (vertical)
- Through the transpyloric plane at L1, this sometimes drifts and becomes through the subcostal line at L3 because it’s easier to find on surface anatomy (horizontal)
- Through the transtubercular line, this goes through the iliac tubercles at the level L5 (horizontal)
What are the contents of the right upper quadrant of the abdomen
- Right lobe of liver
- Gallbladder
- Duodenum
- Head of Pancreas
- Hepatic flexure of colon
- Part of ascending and transverse colon
What are the contents of the left upper quadrant of the abdomen
- Stomach
- Spleen
- Left lobe of liver
- Body of pancreas
- Splenic flexure of colon
- Part of transverse and descending colon
What are the contents of the right lower quadrant
- Cecum
- Appendix
- Ascending colon
- Small intestine
What are the contents of the left lower quadrant
- Small intestine
- Descending colon
- Sigmoid Colon
What process does the digestive system do
- Ingestion
- Secretion of digestive fluids
- Mixing and propulsion
- Digestion
- Absorption
- Defacation
Describe the serous layer of the GI tract
the outer membrane; encloses several body cavities; secrete a lubricating fluid; outer epithelial layer (secretory) and inner layer (connective tissue with vessels)
Describe the muscular layer of the GI tract
- The middle layer
- longitudinal or circular; responsible for movement of lumen contents
Describe the mucosal layer of the GI tract
- inner layer; lines internal organs or cavities exposed to external environment; secrete mucus
- also involved in absorption
What are the 3 types of layers of the GI tract
- Serous
- Muscular
- Mucosal
What are the divisions of the GI tract in order
- Oral cavity
- Pharynx
- Oesophagus
- Stomach
- Small intestine (duodenum, jejunum, ilieum)
- Large intestine (colon)
Epiglottis
- flap of cartilage located in the throat behind the tongue and in front of the larynx
- Will fall down and cover the trachea and larynx during swallowing to prevent any digested material from getting into the respiratory tract
Contents and role of the oral cavity
- Teeth - Accessory organs, assist with mechanical digestion
- Palate - Roof of mouth, soft palate blocks nasal cavity during swallowing
- Tongue - Accessory organ, taste, assist mixing, swallowing
- Salivary glands - Secretion of saliva (dissolve foods)
Role of the pharynx
- Directs food to oesophagus
- Blocks entry to trachea
Describe anatomy of the oesophagus
- Muscular tube roughly 25 cm long
- Posterior to trachea
- Pierces diaphragm at oesophageal hiatus
- Upper edge is the pharynx
- Opens into the stomach
At what level is the oesophageal hiatus
T10
Describe anatomy of the stomach
- Most dilated part of alimentary canal
- Between oesophagus and small intestine
- J-shaped
- lies under the diaphragm and under the heart
- 2 openings, curvatures, surfaces
- Mechanical (muscle) and chemical (gastric juices) digestion
Cardial orifice
The link of the stomach to the oesophagus
Pyloric orifice
The link of the stomach to the small intestine (duodenum)
What is the superior border of the stomach
Lesser curvature
What is the inferior border of the stomach
Greater curvature
What are the 2 sphincters at the ends of the stomach
- Pyloric sphincter (surrounds pyloric orifice)
- Cardial sphincter (surrounds cardial orifice)
What are the 3 layered muscles of the stomach
- Longitudinal
- Circular
- Oblique
Describe the small intestine
- Convoluted tube - allows time for digestion and absorption
- Runs from pylorus of stomach to ileocaecal junction
- 5 metres in length
- Subdivided into: Duodenum, Jejunum, Ileum
- Where digestion and absorption take place
Describe the duodenum
- About 20-25 cm long
- Retroperitoneal
- C shaped
- Where the duct from the pancreas + gall bladder open (bile and pancreatic juices)
What are the 4 parts of the duodenum in order
- Superior
- Descending
- Horizontal
- Ascending
Where does the duodenum end
Duodenal-jejunal flexure
Describe the jejunum/ileum (almost impossible to find the transition from one to the other)
- At least 3 m long
- From duodenal - jejunal flexure to ileocaecal junction
- Site of absorption: large surface area, further increased by circular folds + villi + microvilli; motility
- Motility: one attached and one free edge
Describe the large intestine
-Terminal division of the GI tract – from end ileum to anus
-1.5 m length; greater cross section compared to small intestine
-4 parts
-Ascending/descending are retroperitoneal
-Absorption of water, from faeces and expelling these
(defecating)
-Rectum / Anus – sphincters close outside world except
when defecating
What are the 4 parts of the large intestine in order
- Ascending
- Transverse
- Descending
- Sigmoid
Name the arterial, venous, lymphatic, sympathetic and parasympathetic supply of the foregut
Arterial: Celiac Venous: Hepatic portal vein Lymphatic: Celiac nodes Sympathetic: Celiac ganglia Parasympathetic: Vagus
Name the arterial, venous, lymphatic, sympathetic and parasympathetic supply of the midgut
Arterial: Superior mesenteric Venous: Superior mesenteric Lymphatic: Superior mesenteric nodes Sympathetic: Superior mesenteric ganglia Parasympathetic: Vagus
Name the arterial, venous, lymphatic, sympathetic and parasympathetic supply of the hindgut
Arterial: Inferior mesenteric Venous: Inferior mesenteric Lymphatic: Inferior mesenteric nodes Sympathetic: Inferior mesenteric ganglia Parasympathetic: Pelvic splanchnic
What does the superior mesenteric and its branches supply
Distal part of duodenum to the proximal 2/3 of transverse colon
What branches does the superior mesenteric artery give off
- Jejunal and ileal branches
- Middle colic
- Right colic
- Ileocaecal
Arterial arcades
a series of anastomosing arterial arches between the arterial branches of the jejunum and ileum.
What does the inferior mesenteric artery and its branches supply
Distal 1/3 of transverse colon to half way down anal canal
What branches does the inferior mesenteric artery give off
- Left colic
- Sigmoid
- Superior rectal
What are the glands associated with the gut
- Liver
- Spleen
- Gall bladder
- Pancreas
