GI Flashcards
Foregut
Pharynx to duodenum
Midgut
Duodenum to proximal 2/3 of transverse colon
Hindgut
Distal 1/3 of transverse colon to anal canal above pectinate line
Omphalocele
Persistence of herniation of abdominal contents into umbilical cord, sealed by peritoneum.
Gastroschisis
Extrusion of abdominal contents through nonfused lateral abdominal walls
Rostral fold failure
caudal fold failure
Rostral – sternal defects
Caudal fold failure – bladder extrophy
Midgut development 6 weeks-10
Midgut herniates through ring and by the 10th returns to abdominal cavity and rotates around SMA
Duodenal atresia
Associated with trisomy 21, duodenum isn’t canalized causes double bubble sign and bilous vomiting.
Apple peel atresia
In jejunum, ileum, colon, due to vascular accident.
Esophageal atresia with TE fistula
Most common, vomiting, drooling, choking with first feeding. TEF allows air to enter stomach.
Cyanosis is due to laryngospasm to prevent reflux related aspiration.
Diagnose with failure to pass NG tube.
Also polyhydramnios due to lack of swallowing
Congenital pyloric stenosis
Doesn’t appear right away. Usually happens in firstborn males. Few weeks later there is projectile vomiting with palpable epigastric olive mass. Nonbilous.
Behcet syndrome
Recurrent apthous ulcers, uviitis, and genital ulcers. Due to small vessel immune complex vasculitis
Pancreas derived from…
Foregut. Ventral pancreatic buds rotate and contribute to pancreatic head and main pancreatic duct. Uncinate process is formed by the ventral bud alone.
Annular pancreas
Failure of ventral bud fusion that encircles the second part of the duodenum. Can cause duodenal narrowing.
Pancreas divisum
Ventral and dorsal parts fail to fuse
Spleen
Derived from mesoderm, but is supplied by foregut – celiac artery
Retroperitoneal structures
SAD PUCKER Suprarenals (adrenals) Aorta and IVC Duodenum 2-4 Pancreas (but not tail) Ureters Colon (ascending and descending) Kidneys Esophagus (lower 2/3) Rectum (partially)
Falciform ligament
Connects liver to anterior abdominal wall – contains the ligamentum teres hepatus (derivative of fetal umbilical vein)
Hepatoduodenal
Connects liver to duodenum. Contains the portal triad(portal vein, hepatic artery, common bile duct). Borders omental foramen
Pringle maneuver
Press on hepatoduodenal ligament to stop bleeding.
Gastrohepatic
Connects liver to lesser curvature of stomach and contains gastric arteries. Separates the greater and lesser sacs and may be cut during surgery to access the lesser sac
Gastrocolic
Connects greater curvature of stomach to transverse colon. Contains the gastroepiploic arteries. Part of the greater omentum.
Gastrosplenic
Connects greater curvature and spleen. Contains the short gastric arteries and the left gastroepiploic vessels. Separates the greater and lesser sacs on the left.
Splenorenal
Connects spleen to posterior abdominal wall. Contains the splenic artery and vein, and the tail of the pancreas
Layers of the digestive tract
Mucosa - contains epithelium, lamina propria, and muscularis propria
Submucosa- includes the submucosal nerve plexus (meissners)
Muscularis propria - Includes myenteric plexus between inner circumferential and outer longitudinal muscle
Frequencies of contractions in digestive tract
Stomach is slow, duodenum is fast, ileum/cecum is medium (8-9 waves)