First Aid Anatomy Flashcards
Layers of gut wall from inside to outside
MSMS
Mucosa (epithelium, lamina propria, muscularis mucosa)
Submucosa includes Submucosal nerve (Meissner) Secretes fluid
Muscularis externa includes Myenteric nerve plexus (Auerbach), Motility
Serosa (when intraperitoneal) adventitia (when retroperitoneal)
Ulcers location
can extend into submucosa, inner or outer muscular layer
Erosions location
in the mucosa only
Frequencies of basal electric rhythm (slow waves)
Stomach
3 waves/min
Frequencies of basal electric rhythm (slow waves)
Duodenum
Duodenum 12 waves/min
Frequencies of basal electric rhythm (slow waves)
Ileum
Ileum 8-9 waves/min
Esophagus histology
Nonkeratinized stratified squamous epithelium
Stomach histology
Gastric glands
Duodenum histology
Villi and microvilli ^ absorptive surface
Brunner glands (HCO3- secreting cells of submucosa) and crypts of Lieberkuhn (contain stem cells that replace enterocytes/goblet cells and Paneth cells that secrete defensins, lysozyme and TNF
Jejunum histology
Plicae circulares (also present in distal duodenum) and crypts of Lieberkuhn
Ileum histology
- Peyer patches (lymphoid aggregates in lamina propria, submucosa)
- Plicae curculares (proximal ileum)
- and crypts of Lieberkuhn
- Largest number of goblet cells in the small intestine
The location of the largest number of goblet cells in the small intestine
Ileum
Colon histology
Crypts of Lieberkuhn but no Villi
Abundant goblet cells
Foregut artery
Celiac
Midgut artery
SMA
Hindgut artery
IMA
Foregut parasympathetic innervation
Vagus
Midgut parasympathetic innervation
Vagus
Hindgut parasympathetic innervation
Pelvic
Foregut vertebral level
T12/L1
Midgut vertebral level
L1
Hindgut vertebral level
L3
Midgut artery
SMA
Hindgut artery
IMA
Hindgut parasympathetic innervation
Pelvic
Hindgut vertebral level
L3
Midgut vertebral level
L1
Watershed regions of the GI tract
two areas of the colon -> susceptible in colonic ischemia
Splenic flexure - SMA and IMA
Rectosigmoid junction - the last sigmoid arterial branch from the IMA and superior rectal artery
Superior mesenteric artery syndrome
Characterized by intermittent intestinal obstruction symptoms (primarily postprandial pain) when SMA and aorta compress transverse (third) portion of duodenum
Typically occurs in conditions associated with diminished mesenteric fat (eg low body weight/malnutrition)
Arteries supplying GI tract are?
single and branch anteriorly
Arteries supplying non-GI structures are?
paired and branch laterally and posteriorly
