Introduction to the Gastrointestinal and Hepatobiliary Systems PDF

Digestive system - Digestion begins in the mouth. Here the teeth mechanically shred and grind food and enzymes begin the chemical breakdown of carbohydrates. 1. The digestive tract, or alimentary canal, is a muscular tube containing a mucous membrane lining that extends from the mouth to t...

Digestive system - Digestion begins in the mouth. Here the teeth mechanically shred and grind food and enzymes begin the chemical breakdown of carbohydrates. 1. The digestive tract, or alimentary canal, is a muscular tube containing a mucous membrane lining that extends from the mouth to the anus and is approximately 9 m (30 ft) long. 2. Mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus. 3. Peristalsis is the coordinated, rhythmic, sequential contraction (wave-like movement) of smooth muscle that pushes food through the digestive tract, as well as bile through the bile duct. 4. Accessory organs (The teeth, tongue, salivary glands, liver, gallbladder, pancreas, and appendix) aid in the digestive process but are **[not]** considered part of the digestive tract. 5. Accessory organs release chemicals into the system through a series of ducts and are discussed here shortly. b. Organs of the Digestive System and Their Functions Box 45.1 (below) lists various organs of the digestive system and the accessory organs involved in digestion. 1. Mouth marks the entrance to the digestive system and is the floor of the mouth containing a muscular appendage. Involved in swallowing, and the formation of speech. Tiny elevations, called papillae, contain the taste buds which can differentiate among bitter, sweet, sour, and salty sensations. 2. Teeth. Each tooth is designed to carry out a specific task. At the front of the mouth are the incisors, which are structured for biting and cutting. Posterior to the incisors are the canines, pointed teeth used for tearing and shredding food. The molars are to the rear of the jaw. These teeth have four cusps (points) and are used for mastication (the crushing and grinding of food). 3. Salivary glands. The three pairs of salivary glands are the parotid, submandibular, and sublingual glands. They secrete fluid called saliva, which is approximately 99% water with enzymes and mucus. Once food enters the mouth, the secretion increases to lubricate and dissolve the food and to begin the chemical process of digestion. The salivary glands secrete about 1000 to 1500 mL of saliva daily. The major enzyme is salivary amylase (ptyalin), which initiates carbohydrate metabolism. Another enzyme, lysozyme, destroys bacteria and thus protects the mucous membrane from infections and the teeth from decay. 4. Esophagus. The esophagus is a muscular, collapsible tube that is approximately 25 cm (10 in) long, extending from the mouth through the thoracic cavity and the esophageal hiatus (a hole in the diaphragm) to the stomach. Digestion does not take place in the esophagus. Peristalsis moves the bolus (food broken down and mixed with saliva, ready to pass to the stomach) through the pharynx, to the esophagus, and then to the stomach in 5 or 6 seconds. 5. Stomach. The stomach is in the left upper quadrant of the abdomen, directly inferior to the diaphragm (Fig. 45.2). A filled stomach is the size of a football and can hold a volume of approximately 1 to 1.5 L. The stomach entrance is at the cardiac sphincter (so named because it is close to the heart); the exit is at the pyloric sphincter. As food leaves the esophagus, it enters the stomach through the relaxed cardiac sphincter. The sphincter then contracts, preventing reflux (splashing or return flow), which can be irritating to the esophagus. The gastric juices are secretions released by the gastric glands. Digestion of protein begins in the stomach. Hydrochloric acid softens the connective tissue of meats, kills bacteria, and activates pepsin (the chief enzyme of gastric juices that converts proteins into proteoses and peptones). Mucin is released to protect the stomach lining. Intrinsic factor (a substance secreted by the gastric mucosa) is produced to allow absorption of vitamin B12. The stomach breaks the food down into a viscous, semiliquid substance called chyme. The chyme passes through the pyloric sphincter into the duodenum for the next phase of digestion. 6. Small intestine. The small intestine is a tube that is 6 m (20 ft) long and 2.5 cm (1 in) in diameter. It begins at the pyloric sphincter, ends at the ileocecal valve, and is divided into three major sections: duodenum, jejunum, and ileum. Up to 90% of digestion takes place in the small intestine. The intestinal juices finish the metabolism of carbohydrates and proteins. Bile and pancreatic juices enter the duodenum. Bile from the liver breaks molecules into smaller droplets, which enables the digestive juices to complete their process. Pancreatic juices contain water, protein, inorganic salts, and enzymes. Pancreatic juices are essential in breaking down proteins into their amino acid components, in reducing dietary fats to glycerol and fatty acids, and in converting starch to simple sugars.The inner surface of the small intestine contains millions of tiny finger-like projections called villi, which are clustered over the entire mucous membrane surface. The villi aid in the digestive process by absorbing the products of digestion into the bloodstream. They increase the absorption area of the small intestine by about 600 times. Inside each villus is a rich capillary bed, along with modified lymph capillaries called lacteals. The primary function of the lacteals is to absorb metabolized fats. 7. Large intestine. Once the small intestine has completed its tasks of digestion, the ileocecal valve opens and releases the contents of digestion into the large intestine. The large intestine is a tube that is larger in diameter (6 cm, or 2 in), but shorter at 1.5 to 1.8 m (5 to 6 ft), than the small intestine. The large intestine consists of the cecum; appendix; ascending colon, hepatic flexure, transverse colon, splenic flexure, descending colon, and sigmoid colon; rectum; and anus. This is the terminal portion of the digestive tract, where the process of digestion is completed. The large intestine has four major functions: - \(1) completion of absorption of water - \(2) manufacture of certain vitamins (such as vitamins K and B7 - \(3) formation of feces - \(4) expulsion of feces. 8. Rectum. The rectum is the last 20 cm (8 in) of the intestine, where fecal material is expelled. The anus is the opening to the outside of the body, where feces are passed. c. Accessory organs of digestion 1. The liver is the largest glandular organ in the body, weighing approximately 1.5 kg (3 to 4 lb) in the adult, and is one of the more **complex organs** in the body. It is located just inferior to the diaphragm, covering most of the upper right quadrant and extending into the left epigastrium, and it is divided into two lobes. and further divided into several lobules containing small blood vessels. Approximately 1500 mL of blood is delivered to the liver every minute by the portal vein and the hepatic portal artery. The cells of the liver produce a product called bile, a yellow-brown or green-brown liquid; bile is necessary for the emulsification of fats. The liver releases approximately 500 to 1000 mL of bile per day, which then travels to the gallbladder through hepatic ducts. The gallbladder is a sac about 8 to 9 cm (3 to 4 in) long, located on the right inferior surface of the liver. Bile is stored in the gallbladder until it is needed for fat digestion. In addition to producing bile, the liver's functions include managing blood coagulation; metabolizing proteins, fats, and carbohydrates; manufacturing cholesterol; manufacturing albumin to maintain normal blood volume; filtering out old red blood cells (RBCs) and bacteria; detoxifying poisons (alcohol, nicotine, drugs); converting ammonia to urea; providing the main source of body heat at rest; storing glycogen for later use; activating vitamin D; and breaking down nitrogenous waste (from protein metabolism) to urea, which the kidneys can excrete as waste from the body 2. GallbladderThe gallbladder is a pear-shaped organ measuring approximately 7 to 10 cm (3 to 4 in) long. Areolar connective tissue connects it to the underside of the liver. The gallbladder can store 30 to 50 mL of bile, and its primary function is to store and eject bile into the duodenum for digestion of fats. 3. PancreasThe pancreas is an elongated gland, approximately 12 to 15 cm (6 to 9 in) long, which lies posterior to the stomach. It is involved in endocrine and exocrine duties. In this chapter, discussion of the pancreas is limited to its exocrine activities. Each day the pancreas produces 1000 to 1500 mL ofpancreatic juice to aid in digestion. This pancreatic juice contains the digestive enzymes protease (trypsin), lipase (steapsin), and amylase (amylopsin). These enzymes are important because they digest the three major components of chyme: proteins, fats, and carbohydrates. The enzymes are transported through an excretory duct to the duodenum. This pancreatic duct connects to the common bile duct from the liver and gallbladder and empties through a small orifice in the duodenum called the major duodenal papilla. In addition, the pancreas contains an alkaline substance, sodium bicarbonate, which neutralizes hydrochloric acid in the gastric juices that enter the small intestine from the stomach. d. Regulation of food intake 1. The hypothalamus, a portion of the brain, contains two appetite centers that affect eating. One center stimulates the individual to eat, and the other signals the individual to stop eating. 2. These centers work in conjunction with the rest of the brain to balance eating habits. In addition to the hypothalamus, factors that also affect food intake include lifestyle, culture, eating habits, emotions, and genetics. a\. Diagnostic test: upper gastrointestinal study (upper GI Series, UGI). \(2) Nursing interventions and patient teaching: \(a) Instruct patient to remain NPO (nothing by mouth) and avoid smoking after midnight. \(b) Explain the importance of rectally expelling all barium after the examination. \(c) Inform the patient that the stool will be light in color. \(d) Instruct the patient to increase fluid intake to expel barium and prevent constipation or blockage. b\. Diagnostic test: tube gastric analysis. 1. Stomach contents are aspirated to determine the amount of acid produced by \(2) Nursing interventions and patient teaching: \(a) Instruct patients to remain NPO after midnight and that any anticholinergic medications will be held for 24-hours before the test so the gastric acid secretion will not be altered. b. Because nicotine stimulates the flow of gastric secretions, instruct patient not \(c) Explain that a nasogastric tube will be inserted into the stomach to aspirate gastric content. \(d) Send specimens immediately to the laboratory. c\. Diagnostic test: Esophagogastroduodenoscopy (EGD, UGI Endoscopy, Gastroscopy). \(1) Direct visualization of a hollow organ or cavity by means of a long, flexible fiberoptic scope. It visualizes the esophagus, stomach, and duodenum for routine screening was well as examination of tumors, varices, mucosal inflammations, hiatal hernias, polyps, ulcers, presence of helicobacter pylori, strictures, and obstructions. \(a) Can remove polyps, coagulate sources of active GI bleeding and perform sclerotherapy or esophageal varices through endoscopy. \(b) Enteroscopy (longer fiberoptic scope) can also be used to evaluate the esophagus, stomach duodenum and upper small intestine. \(2) Nursing interventions and patient teaching: \(a) Explain the procedure to the patient and tell them that they will be NPO after midnight. \(c) Inform the patient that he/she will receive a preoperative intravenous sedative such as midazolalm (Versed). \(d) Explain to the patient that he/she will not be able to eat or drink until the gag reflex returns. \(e) Assess the patient for signs and symptoms of perforation, including abdominal pain and tenderness, guarding, oral bleeding, melena and hypovolemic shock. d\. Diagnostic test: Capsule Endoscopy a. Patient swallows a capsule (approximately the size of a vitamin) containing a camera that provides endoscopic evaluation of the GI Tract. b. Used to visualize the small intestine and diagnose diseases such as Crohn's disease, celiac disease, and malabsorption syndrome. c. Examination takes 8 hours, taking tens of thousands of images. The capsule relays images to a data recorder that the patient wears on a belt. After the exam, the images are reviewed on a monitor. 2. Nursing Interventions: a. Patient NPO for 12 hours before test and no smoking for 24 hours before the test. b. Patient will be NPO for 2 hours after swallowing the capsule c. Patient can usually eat 4 hours after swallowing the capsule d. Peristalsis will cause passage of the disposable capsule with a bowel movement, usually within 2 to 3 days or sooner, depending on the patient's rate of peristalsis e. The pill camera does not have to be retrieved d\. Diagnostic test: barium swallow/gastrografin studies. \(1) Provides a more thorough study than most UGI examinations. It provides a clearer view of the esophagus because esophageal movements do not show up well on x-ray. \(2) Detects defects in the luminal filling. Such as: tumors, scarred strictures, and esophageal varices. And anatomical abnormalities such as: \(a) Hiatal hernia. \(b) Cancers of the esophagus. \(c) Gastroesophageal reflux disease. \(d) Ulcers and muscle disorders. NOTE: Gastrografin is now used in place of barium for patients with GI bleed and where surgery is being considered. Gastrografin is water soluble and rapidly absorbed. If Gastrografin escapes from the GI tract, it is easily absorbed by surrounding tissue, but complications can occur if barium leaks from the GI tract. \(2) Nursing interventions and patient teaching: same as Upper GI series. e\. Diagnostic test: esophageal function studies (Bernstein Test). \(1) The Bernstein Test (acid-perfusion test) is used to produce the symptoms of gastroesophageal reflux. \(a) Used to differentiate esophageal pain from angina pectoris. b. The test is positive for esophageal reflux if the patient suffers pain with the \(2) Nursing interventions and patient teaching: \(a) Explain that they will be NPO 8 hours prior to procedure and medications that may interfere with the production of acid, such as antacids and analgesics will be held. \(b) Patient needs to participate in the procedure so avoid sedating. \(c) Explain to patients that they will be asked to swallow and describe any discomfort during the instillation of hydrochloric acid. f\. Diagnostic test: examination of stool for occult blood. \(1) A benign or malignant GI tumor should be expected if occult blood (blood that is obscure or hidden from view) is detected in the stool. Usually the bleeding is so slight that gross blood is not seen in the stool. A tumor may ulcerate and bleeding occur. \(2) Nursing interventions and patient teaching: instruct patient to collect the stool specimen, ensuring it is free from urine and toilet paper, because it could possibly contaminate the specimen or alter the test results. g\. Diagnostic test: sigmoidoscopy (Lower GI Endoscopy). \(1) Sigmoidoscopy allows visualization of the lower GI tract and, if indicated, access to obtain biopsy specimens of tumors, polyps, or ulcerations of the anus, rectum and sigmoid colon. \(a) Direct visualization through sigmoidoscopy is beneficial because the lower GI tract is difficult to visualize radiographically. b. Diagnoses of many lower bowel disorders can be obtained through NOTE: There are 3 basic tests for colon cancer: a stool test (to check for blood); sigmoidoscopy (inspection of the lower colon); and colonoscopy (inspection of the entire colon). All 3 are effective in catching cancers in the early stages, when treatment is most beneficial. (Foundations 8^th^ Edition) \(2) Nursing interventions and patient teaching: \(a) Inform the patient of the procedure and obtain the patient's signature on the consent form for the procedure. \(b) Administer enemas per order the evening prior and/or the morning before the examination. \(c) Following the procedure, monitor for evidence of bowel perforation (Abdominal pain, tenderness, distention, and bleeding). h\. Diagnostic test: barium enema study (Lower GI Series). \(1) The barium enema (BE) study can detect the presence and location of polyps, tumors, diverticula, and positional abnormalities (such as malrotation). \(a) Barium sulfate is more effective for visualizing mucosal detail. b. The BE study may be used therapeutically to reduce nonstragulated ileocolic \(2) Nursing interventions and patient teaching: \(a) The evening before or the morning of the BE, administer cathartics such as \(c) Assess the patient after the BE, ensuring all barium (stool light in color) had been expelled. If the patient fails to expel all barium, it could cause hardened impaction. i\. Diagnostic test: colonoscopy. 1. The fiberoptic colonoscope examines the entire colon-from anus to cecum \(2) Nursing interventions and patient teaching: \(a) Explain to the patient that he/she needs to sign a consent form before the procedure. b. Instruct patient to restrict his/her diet to liquids for 1 to 3 days prior to the \(c) The physician may order an enema and GoLYTELY, both used as cathartics to decrease the residue in the bowel. \(d) Explain that 1 gallon of GoLYTELY must be taken over a 2-hour period. \(f) A sedative such as Versed is often given before the procedure. \(g) After the procedure, assess for evidence of bowel perforation, hypovolemic shock and examine the stool for gross blood. j\. Diagnostic test: stool culture. \(1) The physician may order a stool for culture to test for the presence of bacteria, ova and parasites. Many bacteria (such as Escherichia coli) are indigenous in the bowel. Bacterial cultures are usually done to detect enteropathogens (such as Staphylococcus aureus, Salmonella, Shigella, E. coli, or Clostridium difficile). The stool is examined for ova and parasites (O&P) when a patient is suspected of having a parasitic infection. \(2) Nursing interventions and patient teaching: \(a) Instruct the patient that if an enema is required to collect a stool specimen, the only solution that can be used is normal saline or tap water. Any other solution such as soap could affect the viability of the organisms collected. \(b) Instruct the patient not to mix urine with feces and the stool specimen is collected prior to barium examinations. c. Once the specimen has been obtained, it should be taken to the lab within 30 a\. Liver: \(1) Largest and one of the most complex glandular organs in the body. \(2) Located just inferior to the diaphragm, covering most of the right upper quadrant and extending into the left epigastrium. \(3) Divided into two lobes. \(4) Receives approximately 1500 ml/minute of blood via the portal vein and hepatic artery. \(5) Hepatocytes (cells of the liver) produce bile. \(a) Bile is necessary for the metabolism (emulsification) of fats. \(b) Bile travels through the hepatic duct to the gall bladder for storage. \(6) Functions: \(a) Metabolizes fats. \(b) Manages blood coagulation and produces most of the clotting factors (in the presence of Vitamin K). \(c) Manufactures cholesterol. \(d) Manufactures albumin (maintains normal blood volume). \(e) Filters out old red blood cells and bacteria. \(f) Detoxifies poisons (alcohol, nicotine, drugs). \(g) Converts ammonia to urea. \(h) Provides the main source of body heat. \(i) Stores glycogen for later use. \(j) Activates Vitamin D. \(k) Breaks down nitrogenous wastes to urea. b\. Gall Bladder: \(1) Sac about 3 to 4 inches long located on the right inferior surface of the liver. \(2) Stores bile needed for fat digestion. c\. Pancreas: \(1) Elongated gland that lies posterior to the stomach. \(2) Involved in both exocrine and endocrine function. \(3) Produces 1000 to 1500 ml of pancreatic juice daily to aid in digestion. \(4) Digests the three major components of chyme: proteins, fats and carbohydrates. \(5) Contents of pancreatic juice. \(a) Protease (Trypsin). \(b) Lipase (Steapsin). \(c) Amylase (Amylopsin). \(6) Enzymes are transported to the duodenum via the pancreatic duct to the common bile duct and out to the duodenum via the papilla of Vater. d\. The liver, gallbladder and exocrine pancreas all play an important role in digestion. 3\) Total bilirubin: 0.1-1.0 mg/dl. \(b) Rationale: Testing for bilirubin in the blood provides information for diagnosis and evaluation of liver disease, biliary obstruction and hemolytic anemia. 1\) Elevated levels will cause jaundice, which is the most common sign of a liver disorder. a\) Old red blood cells are broken down by the spleen and bone marrow. 1. The hemoglobin which is released is converted into indirect bilirubin. This bilirubin is carried by the blood to the liver, where it is converted to direct bilirubin. The bilirubin then enters the bile ducts and makes its way to the intestines. \(c) Nursing interventions: 1\) Keep patient NPO until blood specimen is drawn. 2\) Monitor venipuncture site for bleeding. 3\) Apply pressure for 5 minutes if patient has a problem with clotting. 2. Liver Enzymes: \(a) Rationale: The liver is a storehouse of enzymes. 1\) Injury or disease will cause release of these intracellular enzymes into the bloodstream and their levels will be elevated. 2\) Some of these enzymes are produced in other organs so elevations may not be specific to the liver. \(b) AST (aspartate aminotransferase): formerly serum SGOT. 1\) Normal value: adult 0 to 35 IU/L. 2\) Elevated in myocardial infarction, hepatitis, cirrhosis, hepatic necrosis, hepatic tumor, acute pancreatitis, acute renal disease and acute hemolytic anemia. \(c) ALT (alanine aminotransferase): formerly SGPT. 1\) Normal value: adults/child 4 to 36 IU/L. 2\) Elevated in hepatitis, cirrhosis, hepatic necrosis, hepatic tumors, and by hepatotoxic drugs. \(d) LDH (lactic dehydrogenase): 1\) Normal value: 100 to 190 IU/L. 2\) Elevated in myocardial infarction, pulmonary infarction, hepatic disease, pancreatitis, hemolytic anemia and skeletal muscle disease. \(e) Alkaline phosphatase: 1\) Normal value: adult 30 to 120 IU/ml. 2\) Elevated in obstructive disorders of the biliary tract, hepatic tumors, cirrhosis, primary and metastatic tumors, hyperparathyroidism, metastatic tumor in bones and healing fractures. \(f) Gamma GT (Gamma glutamyl-transferpeptidase): 1\) Normal value: a\) Male / female over 45: 8 to 38 U/L. b\) Female under 45: 5-27 U/L. 2. Elevated in liver cell dysfunction: hepatitis, cirrhosis, hepatic tumors, \(g) Nursing interventions: 1\) Patient teaching. 2\) Assess site for bleeding. 3. Serum Protein Test a. Used to assess the liver's functional status and this is done by measuring the products it synthesizes. b. When a disorder or disease affects liver cells, they lose their ability to synthesize albumin. c. When the albumin falls low, it may result in loss in the urine (i.e. nephrotic syndrome) or into third-space volumes (ascites). d. This test measures, total protein, albumin, albumin/globulin, and globulin. \(a) Normal values: 1\) Total protein: 6 to 8 g/dl. 2\) Albumin: 3.2 to 4.5 g/dl. 3\) Globulin: 2.3 to 3.4 g/dl. 4\) Albumin Globulin (A/G ration): 1.2 to 2.2 g/dl. \(b) Nursing interventions: 1\) Patient education regarding the purpose of the test. 2\) Monitor venipuncture site for bleeding. \(5) Serum Ammonia: \(a) Rationale: byproduct of protein metabolism is converted by liver to urea and excreted by kidneys. 2\) Primarily used as an aid in diagnosis of hepatic encephalopathy and hepatic coma. \(b) Normal value: 10-80 ug/dl \(c) Nursing interventions: list antibiotics patient is taking on lab request as they may affect results. b\. Radiographic studies: \(1) Cholecystography: \(a) Rationale: 1\) Provides visualization of the gallbladder after ingestion of radiopaque contrast. 2\) Requires concentration of the dye within the gallbladder. 3\) Patient must take dye tablets evening prior to test. 4\) Vomiting or diarrhea will cause decreased absorption and affect results. \(b) Nursing interventions: 1\) Interview patient and review medical records to rule out allergy to iodine/contrast medium. 2\) Administer radiopaque tablets as ordered. 3\) NPO after midnight. 4\) May be given high fat diet after test has started to stimulate emptying of the gallbladder. \(2) Intravenous Cholangiography (IVC): \(a) Rationale: 1\) Radiographic dye, injected intravenously, is concentrated by the liver and secreted into the bile duct. 2\) IVC allows visualization of hepatic and common bile ducts and gallbladder if cystic duct is patent. 3\) Used to identify stones, stricture, or tumor of the hepatic duct, common bile duct and gallbladder. \(b) Nursing interventions: same as above, except tablets are not given. \(3) Operative Cholangiography: \(a) Common bile duct is injected with dye which allows surgeon to view this anatomically difficult area before interventions to decrease chance of injuring common bile duct. \(b) Nursing interventions: same as above. \(4) T-tube Cholangiography (Postoperative Cholangiography): \(a) Rationale: 1\) Performed to identify retained stones in the Post-operative cholecystectomy patient. 2\) Performed via a T-tube placed by the surgeon intra-operatively. 3\) Contrast is injected to ensure adequate flow of bile into the duodenum. \(b) Nursing interventions: 1\) Protect the patient from infection by connecting tube to sterile drainage system. 2\) Cover with sterile dressing. 3\) NPO after midnight. \(5) Other Imaging Procedures: \(1) Ultrasonography of Liver, Gallbladder and Biliary System: \(a) Rationale: 1\) Imaging technique in which deep structures are visualized by recording the reflections of ultrasonic waves directed into the tissues. 2\) Good for patient who is allergic to contrast. \(b) Nursing interventions: 1\) NPO after midnight. 2\) Check to see that patient has not had a recent barium enema. (Ultrasound waves cannot penetrate barium). 3\) Explain to patient that they will be lying on a table. 2. Gallbladder Scanning: \(a) Rationale: nuclear medicine scan with radioactive isotope used for the diagnosis of acute cholecystitis. \(b) Nursing interventions: 1\) Educate patient that the small dose of radiation used is harmless. 2\) NPO after midnight. 3\) Encourage patient to drink fluids after test to promote excretion of the radionuclide. 4\) Nursing staff should wear gloves when handling urine. \(6) Tissue Examination: \(1) Needle Liver Biopsy: \(a) Rationale: 1\) Safe, simple and valuable method to diagnose pathological liver conditions. \(b) Nursing interventions: 1\) Explain procedure to patient and obtain informed consent. 2\) Check lab values for coagulation studies. 3\) Observe for bleeding after procedure. 4\) Monitor VS. 5\) Assess for pain, provide analgesics as ordered. 6\) Assess for pneumothorax. 7\) Keep patient lying on right side for 2 hours and flat for 12 to 14 hours. \(7) Radioisotope Liver Scanning: \(a) Rationale: 1\) Used to outline and detect structural changes in liver. 2\) After contrast is injected, gamma-ray device passed over abdomen. 3\) Records distribution of the radioactive particles in the liver. \(b) Nursing interventions: same as above. 3. The Pancreas a. Endoscopic Retrograde Cholangiopancreatography (ERCP): i. Rationale: Fiberoptic duodenoscope inserted through GI tract into duodenum. 2\) Common bile duct and pancreatic duct are visualized after dye is injected. 3\) Used to diagnose pancreatic dysfunction. 4\) Also used to evaluate obstructive jaundice, remove common bile duct stones and place biliary and pancreatic duct stents to bypass obstruction. \(b) Nursing interventions: 1\) NPO after midnight. 2\) Educate patient and sign permit. a\) Test takes 1-2 hours to complete. b\) Patient must lie completely motionless on a hard X-ray table. 3. NPO post-procedure until gag reflex returns. 4. Assess for abdominal pain, tenderness and guarding. 5\) Assess for signs and symptoms of pancreatitis-increased abdominal pain, nausea, vomiting, diminished or absent bowel sounds. e\. Laboratory Tests related to the Pancreas: \(1) Amylase Test: \(a) Normal value: 30 to 220 U/L (SI units). \(b) Rationale: 1\) Test for pancreatitis. 2\) Abnormal serum rise occurs 12 hours after onset of pancreatic disease. 3\) May return to normal within 48 to 72 hours. (Amylase is cleared efficiently by the kidneys). \(c) Nursing interventions: list medications on lab request due to false- positive results. \(2) Serum Lipase Test: \(a) Normal value: 0 to 160 U/L. \(b) Rationale: Elevated in acute pancreatitis. (More specific than amylase for pancreatitis). \(c) Nursing interventions: keep patient NPO after midnight. f\. Imaging Procedures for the Pancreas: \(1) Ultrasonography: \(a) Rationale: used to establish the diagnosis of pseudocyst, pancreatitis, and pancreatic abscess. \(b) Nursing interventions: 1\) NPO after midnight. 2\) Assess abdomen for distention or gas that may interfere with sound waves. \(2) Computed Tomography (CT) of Abdomen: \(a) Rationale: noninvasive accurate test used to diagnose pathological pancreatic conditions such as inflammation, tumor, cyst formation, ascites, aneurysm and cirrhosis of liver. \(b) Nursing interventions: 1\) NPO after midnight. 2\) Decrease patient\'s anxiety to claustrophobia from machine. \"c:\\\\documents and settings\\\\kathleen.d.carroll\\\\my documents\\\\68wm6\\\\phase ii\\\\module 2 - medical surgical nursing\\\\gi - urinary medications\\\\asat\_632\\\\632\_229.doc\"