Gastrointestinal System Flashcards
8 derivatives of the foregut
- Esophagus
- Diaphragm
- Stomach
- Duodenum
- Liver
- Biliary apparatus
- Pancreas
- Spleen
Bile is produced in the _______
Liver
Bile is stored in the ____________
Gall bladder
Two functions of the pancreas
- Endocrine: produce insulin
2. Exocrine: produce proteolytic digestive enzymes
2 derivatives of midgut
- Small intestine
2. Ascending colon
4 derivatives if hindgut
- Transverse, descending, sigmoid colon
- Rectum
- Superior part of anal canal
- Epithelium of urinary bladder & most of urethra
Function of stomodeum
Allows for communication with amniotic fluid
Foregut is supplied by
Celiac artery
Midgut is supplied by
Superior mesenteric artery
Hindgut is supplied by
Inferior mesenteric artery
Polyhydramnios
Too much amniotic fluid
Cause of tracheoesophogeal fistula
Tracheoesophageal septum develops incorrectly in wrong place
Allows trachea to communicate with distal esophagus
Gastroesophageal reflux
Acid from the stomach is not prevented from flowing retrograde into the esophagus
Cause of congenital diaphgragmatic hernia
Failure of pleuroperitoneal canals to become obliterated ➡️ intestines enter thoracic cavity through foramen Bochdalek
Cause of eventration of diaphragm
Diaphragm is poorly muscularized which allows abdominal visecera to ascend into chest and compress the lung
Results in lung hypoplasia
Cause of paralysis of diaphragm
Damage to phrenic nerve during traumatic delivery (usually of large baby)
Cause of infantile hypertrophic pyloric stenosis
Excessive development of the muscle around the pylorus during the first few weeks of life
Outlet is hypertrophied➡️ vomiting
2 types of biliary atresia
- Intrahepatic
2. Extrahepatic
Atelectasis
Collapse of portion of the lung
Bronchiectasis
Abcesses in the lung
Meconium ileus associated with
Cystic fibrosis
Meconium ileus
Meconium is increaed viscosity; so thick it cannot move through the bowel and creates a functional intestinal obstruction in distal ileum
Cause of duodenal atresia
Failure of the gut to recanalize after the normal stage of epithelial proliferation during development
May involve genetic predisposition
Omphalocele
Defect in midline abdominal wall that causes intestines and other abdominal organs (i.e liver) to exist outside the body; covered by perineal membrane
Gastroschisis
Non-midline abdominal wall defect (usually on right side) that causes intestines to be located outside the body
No membrane covers intestines
Not associated with MCA
Cause of malrotation
Failure of normal rotation of the midgut around its mesenteric attachment during development
Leads to absence of normal fixation of the gut to the body wall
3 types of malrotation
- Reversed rotation
- Mixed rotation
- Nonrotation
Ladd’s bands
Run from abnormally placed anterior cecum to the posterior peritoneum and obstruct the duodenum
Volvulus
Sudden twisting if the gut caused by abnormal anchoring of the intestine to the body wall
Causes intestinal obstruction
Cause of jejenal/ ileum atresia
Vascular accidents late during fetal life with ischemic necrosis followed by resorption of the affected regions of the bowel
Cause of intussusception
Section of bowel invaginates into the lumen of the distal bowel creating a complete obstruction
Cause of Meckels diverticulum
Presence of remnant of vitelline duct
Cause of duplication
Failure of recanalization of the intestine following epithelial proliferation during normal development
Ileus
Functional obstruction of peristalsis of the small intestine
Usually results from severe illness
Cause of Hirsphrung disease
Failure of neural crest cells to migrate caudally to the end of the bowel➡️ absence of autonomic innervation in distal bowel (varying lengths)
Prevents bowel from relaxing resulting in functional obstruction
Imperforate anus
Anal or rectal atresia (infant fails to pass meconium normally)
Inguinal hernia
Enlarged opening at the inguinal ring which communicates with the abdomen (loops of bowel in hernia sac)
Yolk sac divided into 3 parts
- Foregut
- Midgut
- Hindgut
