Gastrointestinal Problems Flashcards
1
Q
Functions of the GI system
A
- process food substances
- absorb the products of digestion into the blood
- excrete unabsorbed materials
- provide an environment for microorganisms to synthesize nutrients, such as vit K.
2
Q
Stomach
A
- contains the cardia, fundus, body, and pylorus.
- hydrochloric acid kills microorganisms, breaks food into small particles, and provides a chemical environment that facilitates gastric enzyme activation.
- pepsin is the chief coenzyme of gastric juice, which converts proteins into proteoses and peptones,
- intrinsic factor comes from parietal cells and is necessary for the absorption of vit B12.
- gastrin controls gastric acidity.
3
Q
Small and large intestine
A
- the duodenum contains the openings of the bile and pancreatic ducts; small intestine terminates in the cecum.
- large: absorbs water and eliminates wastes; intestinal bacteria play a vital role in the synthesis of some B vitamins and vit K; the ileocecal valve prevents contents of the large intestine from entering the ileum.
4
Q
Pancreatic intestinal juice enzymes
A
- amylase digests starch to maltose.
- maltase reduces maltose to monosaccharide glucose.
- lactase splits lactose into galactose and glucose.
- sucrase reduces sucrose to fructose and glucose.
- nucleases split nucleic acids to nucleotides.
- enterokinase activates trypsinogen to trypsin.
5
Q
Liver
A
- largest gland in the body.
- contains Kupffer cells, which remove bacteria in the portal blood.
- synthesizes glucose, amino acids, and fats.
- aids in the digestion of fats, carbohydrates, and proteins.
- stores and filters blood (200-400ml of blood)
- secretes bile to emulsify fats (500-1000ml of bile/day).
- hepatic ducts: deliver bile to the gallbladder via the cystic duct and to the duodenum via the common bile duct.
6
Q
Gallbladder
A
- stores and concentrates bile and contracts to force bile into the duodenum during the digestion of fats,
- the sphincter of Oddi is located at the entrance to the duodenum.
- the presence of fatty materials in the duodenum stimulates the liberation of cholecystokinin, which causes contraction of the gallbladder and relaxation of the sphincter of Oddi.
7
Q
Pancreas
A
- exocrine gland: secretes sodium bicarbonate to neutralize the acidity of the stomach contents that enter the duodenum; pancreatic juices contain enzymes for digesting carbohydrates, fats, and proteins.
- endocrine gland: secretes glucagon to raise blood glucose levels and secretes somatostatin to exert a hypoglycemic effect; the islets of Langerhans secrete insulin; insulin is secreted into the bloodstream and is important for carbohydrate metabolism.
8
Q
Diagnostic Procedures: Upper GI Tract Study
A
- examination of the upper GI tract under fluoroscopy after the client drinks barium sulfate.
- preprocedure: withhold foods and fluid for 8h prior to the test.
- postprocedure: a laxative may be prescribed; increase oral fluid intake to help pass the barium; monitor stools for the passage of barium (appear chalky white for 24 to 72h) because barium can cause a bowel obstruction.
9
Q
Diagnostic Procedures: Capsule Endoscopy
A
- a procedure that uses a small wireless camera shaped like a med capsule that the client swallows; the test will detect bleeding or changes in the lining of the small intestine.
- the camera travels through the entire digestive tract and sends pictures to a small box that the client wears like a belt.
- preprocedure: a bowel preparation will be prescribed; the client will need to maintain a clear liquid diet on the evening before the exam; additionally, NPO status is maintained for 3h before and after swallowing the capsule.
10
Q
Diagnostic Procedures: Gastric Analysis
A
- requires the passage of a NG tube into the stomach to aspirate gastric contents for the analysis of acidity (pH), appearance, and volume.
- the entire gastric contents are aspirated, and then specimens are collected every 15 min for 1h.
- histamine or pentagastrin may be adm SC to stimulate gastric secretions.
- esophageal reflux may be diagnosed; a probe is placed just above the the lower esophageal sphincter and connected to an external recording device, which provides a computer analysis and graphic display of results.
- preprocedure: fasting for at least 12h, use of tabacco and chewing gun is avoided for 24-48h.
- postprocedure: may resume normal activities; refrigerate gastric samples if not tested within 4h.
11
Q
Diagnostic Procedures: Upper GI endoscopy
A
- following sedation, an endoscope is passed down the esophagus to view the gastric wall, sphincters, and duodenum; tissue specimens can be obtained.
- prepro: NPO for 6-8h; local anesthetic (spray or gargle) is adm along with med that provides moderate sedation.
- client is positioned on the left side to facilitate saliva drainage and to provide easy access of the endoscope.
- airway patency is monitored and emergency equipment should be readily available.
- postpro: NPO until gag reflex returns (1-2h); monitor for signs of perforation and maintain bed rest for the sedated client until alert.
12
Q
Diagnostic Procedures: Fiberoptic Colonoscopy
A
- study in which the linning of the intestine is visually examined; biopsies and polypectomies can be performed.
- client is positioned on the left side with knees drawn up to the chest.
- prepro: cleansing of the colon is necessary; a clear liquid diet is started ont he day before and NPO should start 4-6h prior the test (avoid red, orange and purple liquids).
13
Q
Diagnostic Procedures: Endoscopic retrograde cholangiopancreatography (ERCP)
A
- examination of the hepatobiliary system is performed via a flexible endoscope inserted into the esophagus to the descending duodenum.
- prepro: NPO 6-8h and moderate sedation during.
- postpro: monitor VS, return of gag reflex, and signs of perforation or peritonitis.
14
Q
Diagnostic Procedures: Magnetic resonance cholangiopancreatography (MRCP)
A
- uses magnetic resonance to visualize the biliary and pancreatic ducts in a noninvasive way.
- pre and postprocedure: same as ERCP.
15
Q
Diagnostic Procedures: Computed tomography (CT) Scan
A
- noninvasive cross-sectional view that can detect tissue densities in the abd, including in the liver, spleen, pancreas, and biliary tree.
- can be performed with or without contrast medium.
- prepro: NPO for at least 4h.
- postpro: no specific care.