GI tract Flashcards
what are the system components of the GI tract
- mouth
- teeth
- tongue
- salivary glands
- oesophagus
- stomach
- gall blader
- liver
- pancreas
- small intestine
- large intestine
- rectum
- anus
at what level does the oesophagus begin and end
C6 to T11
describe the two layers of muscle in the oesophagus
20-40 cm long and 1-2cm wide
what neves control the oesophagus
- right vagus nerve
- right sympathetic trunk
- left vagus nerve
- left sympathetic trunk
how much does a infant and adults stomach hold
infant - 30 ml
adult - 1.5-2L
where is the stomach located
- epigastrium, umbilical and left hypochondrium
what does the enlargement of left supraclavicular lymph nodes suggest
troisiers sign - lead to gastric ulcer, sign of stomach cancer
what happens with congenital hypertrophic pyloric stenosis
- hypertrophy of pylorus - thickening of muscular wall
- gastric obstruction - projectile vomiting
when is congenital hypertrophic pyloric stenosis common
around 4 weeks of age
what sex has the highest incidence of congenital hypertrophic pyloric stenosis
males: females is 5:1
higher incidence in monozygotic twins due to genetic factors
what are the parts of the small intestine
- duodenum
- jejunum
- ilium
what are the parts of the large intestine
- cecum
- colon
- rectum
describe the duodenum
- entirely retroperitoneal
- most fixed part of small intestine
how do duodenal ulcers cause disease
- perforate duodenal wall and allow contents to enter peritoneal cavity and cause peritonitis
- erosion of gastroduodenal artery causes severe haemorrhage
how does para-duodenal hernias cause disease
- intestinal lopp folds around duodenojejunal junction causing strangulation and hernia
how does gallstones in duodenum cause disease
- ulcerate for the eroded funds of gallbladder and enter duodenum from perforation
compare the jejunum with the ileum
- less complex arterial arcades
- longer vasa recta
- more place circulates, thicker and highly filed
- no fat in mesentery
what is meckels diverticulum
- yolk sac remnant extending into umbilical cord
- mimics appendicitis
what is the rule of 2 for meckels diverticulum
- 2% of population
- 2 inches long
- 2 feet proximal to ileocaecal junction
where is the appendix normally found
McBurney’s point
where does appendicitis pain start
peri-umbilical region - visceral pain poorly localised - T10
what is the main blood supply to the large intestine
inferior and superior mesenteric arteries
what does hirschsprungs disease cause
absence of certain nerve ganglion cell bodies in myenteric plexus in wall of bowel
what are the symptoms of hirschsprungs disease
- colon stays contracted
- bowel obstruction normally affecting 1-2 feet of the colon that ends with the rectum
what is volvulus
- twisting of intestinal loop
- sigmoid colon susceptible of extreme mobility
what are colon polyps
- abnormal growth of tissue in the lumen of the intestine
what is diverticulosis
- out pouching of the intestinal mucosa through muscular layer of intestinal wall
- herniation of mucosa through areas of weakness of circular smooth muscle
what is diverticulitis
inflamed or infected diverticula
what is intussusception
invagination of loop of intestine with another section or loop of intestine
what are the symptoms of intussusception
- nausea
- vomiting
- cramps by necrosis of tissue
- red currant jelly stools - mucous and blood
what in a physical exam shows they have intussusception
- sausage shape mass in their abdomen
- fetal position for protection
how is intussusception diagnosed
sonogram preferred over x-ray
what is the partial peritoneum
lines the walls of abdominal and pelvic cavities
what is the visceral peritoneum
covers organs
what is the peritoneal cavity
the potential space between the parietal and visceral layers of peritoneum
where is the supracolic compartment
lies above the transverse mesocolon and contains stomach, liver and spleen
where is the infracolic compartment
lies below the transverse mesocolon and contains the small intestine, ascending and descending colon
what connects the supracoloc and infracolic compartments
paracolic gutters
what is the greater sac
larger portion of the peritoneal cavity
what are the compartments of the peritoneal cavity
- greater sac
- lesser sac
- omental foramen of Winslow
what is the omentum
fold of peritoneum extending from the stomach
where does the coeliac trunk arise from
anterior surface of the abdominal aorta at T12
what does the coeliac trunk immediately divide into
- left gastric
- common hepatic
- splenic
what are the main branches to supply the GI tract
foregut - coeliac trunk
midgut - superior mesenteric artery
hindgut - inferior mesenteric artery
