NCLEX: Gastrointestinal disorders

Gastrointestinal disorders: Diagnostic tests

Focus topic: Gastrointestinal disorders

Many tests provide information that will help direct your care of the patient with a GI problem. Even if you don’t participate in testing, you’ll need to know why the practitioner ordered each test, what the results mean, and what responsibilities you’ll need to carry out before, during, and after the test.

 

Gastrointestinal disorders: Endoscopy

Focus topic: Gastrointestinal disorders

Using a fiber-optic endoscope, the doctor can directly view hollow visceral linings to diagnose inflammatory, ulcerative, and infectious diseases; benign and malignant neoplasms; and other esophageal, gastric, and intestinal mucosal lesions. Endoscopy can also be used for therapeutic interventions or to obtain biopsy specimens.

Lower GI endoscopy
Lower GI endoscopy, also called colonoscopy or proctosigmoidoscopy, helps diagnose inflammatory and ulcerative bowel disease, pinpoints lower GI bleeding, and detects lower GI abnormalities, such as tumors, polyps, hemorrhoids, and abscesses.

Nursing considerations
• Tell the patient that he will need to undergo a bowel preparation consisting of laxatives and enemas for 1 or 2 days before the procedure.
• Tell him that he must maintain a clear liquid diet the day before the procedure and then fast the morning of the test.
• Explain that he should review the medications he should take before the procedure with his practitioner.

Try to relax

Focus topic: Gastrointestinal disorders

  • If the patient will undergo a sigmoidoscopy, explain that he most likely won’t be sedated; if he will undergo a colonoscopy, tell him he’ll be under I.V. sedation.
  • Inform the patient that the doctor will insert a flexible tube into his rectum.
  • Tell him that he may feel some lower abdominal discomfort and the urge to move his bowels as the tube is advanced. To control the urge to defecate and ease the discomfort, instruct him to breathe deeply and slowly through his mouth.
  • Explain that air may be introduced into the bowel through the tube. If he feels the urge to expel some air, tell him not to try to control it.
  • Tell him that he may hear and feel a suction machine removing any liquid that may obscure the doctor’s view, but it won’t cause any discomfort.
  • Let him know he can eat after recovering from the sedative, usually about 1 hour after the test.
  • If air was introduced into the bowel, the patient may pass large amounts of flatus. Explain that this is normal and helps prevent abdominal cramping.
  • Tell him to report any blood in his stool.

Upper GI endoscopy

Focus topic: Gastrointestinal disorders

Upper GI endoscopy, also called esophagogastroduodenoscopy, identifies abnormalities of the esophagus, stomach, and small intestine, such as esophagitis, inflammatory bowel disease, Mallory-Weiss syndrome, lesions, tumors, gastritis, and polyps. During endoscopy, biopsies may be taken to detect the presence of Helicobacter pylori or to rule out gastric carcinoma.

Nursing considerations
• Tell the patient that he must restrict food and fluids for at least 6 hours before the test.
• If the test is an emergency procedure, inform the patient that he’ll have his stomach contents suctioned to permit better visualization.
• Explain that he’ll be given I.V. sedation to help keep him comfortable.

I can’t feel my lipths…

Focus topic: Gastrointestinal disorders

  • Before insertion of the tube, the patient’s throat will be sprayed with a local anesthetic. Explain that the spray will taste unpleasant and will make his mouth feel swollen and numb, causing difficulty swallowing.
  • Reassure the patient that he’ll have a mouth guard to protect his teeth from the tube.
  • Before the test, ask the patient to remove dentures and dental appliances, as applicable.
  • Tell the patient that he can expect to feel some pressure in the abdomen and some fullness or bloating as the tube is inserted and advanced and as air is introduced to inflate the stomach.
  • The patient can resume eating when his gag reflex returns — usually in about 1 hour.

Gastrointestinal disorders: Laboratory tests

Focus topic: Gastrointestinal disorders

Common laboratory tests used to diagnose GI disorders include studies of stool, urine, and esophageal, gastric, and peritoneal contents as well as percutaneous liver biopsy.

24-hour pH testing
The lower esophageal sphincter (LES) normally prevents gastric reflux. However, if this sphincter is incompetent, the recurrent backflow of acidic juices (and of bile salts, if the pyloric sphincter is also incompetent) into the esophagus inflames the esophageal mucosa. This inflammation (esophagitis) causes burning epigastric or retrosternal pain that radiates to the back or arms. To distinguish such pain from angina pectoris, patients who also complain of chest pain would have received cardiac testing to eliminate that possibility.
Performed on an outpatient basis, 24-hour pH testing provides 24 hours of continuous acidity data.

Dear Diary…

Focus topic: Gastrointestinal disorders

At the same time, the patient keeps a diary of activities — such as walking, sitting, lying down, and eating — and signs and symptoms — such as burping, vomiting, and chest pain. Then the diary and the data from the 24-hour pH study are entered into a computer, which compares the patient’s symptoms and activities with acid levels to determine the severity of the reflux disease.
Although 24-hour pH monitoring provides accurate results, it’s an uncomfortable procedure. A shorter monitoring period may provide the same results, with less discomfort to the patient.

Nursing considerations
• Document medications the patient takes for reflux, including the date and time of the last dose.
• Tell the patient not to use any antacids, chewing gum, lozenges, or hard candy during the study.
• Encourage him to follow his usual routine so that the study can accurately demonstrate the correlations between activities and reflux disease.
• To help relieve throat discomfort, tell the patient to suck ice chips or use dyclonine hydrochloride (Cepacol) spray.
• To help prevent reflux, tell the patient to avoid large meals, caffeine, alcohol, and lying in a supine position after meals.

Gastrointestinal disorders

Fecal studies
Normal stool appears brown and formed but soft. Narrow, ribbon like stool signals spastic or irritable bowel, or partial bowel or rectal obstruction. Diet and medication can cause constipation. Diarrhea may indicate spastic bowel or viral infection. Soft stool mixed with blood and mucus can signal bacterial infection; mixed with blood and pus, colitis.
Yellow or green stool suggests severe, prolonged diarrhea; black stool suggests GI bleeding or intake of iron supplements or raw-to-rare meat. Tan or white stool shows hepatic-duct or gallbladder-duct blockage, hepa titis, or cancer. Red stool may signal colon or rectal bleeding, but some drugs and foods can also cause this coloration.
Most stool contains 10% to 20% fat. However, higher fat content can turn stool pasty or greasy — a possible sign of intestinal malabsorption or pancreatic disease.

Nursing considerations
• Collect the stool specimen in a clean, dry container.
• Don’t use stool that has been in contact with toilet-bowl water or urine.

Gastrointestinal disorders

• Send the specimen to the laboratory immediately for accurate results.
• Keep in mind that serial stool specimens are usually collected once per day with the first morning stool.
• Instruct the patient being tested for fecal occult blood to avoid eating red meat, poultry, fish, turnips, or horseradish or taking iron preparations, ascorbic acid (vitamin C), or anti-inflammatory agents for 48 to 72 hours before the specimens are collected.
• Use commercial Hemoccult slides as a simple method of testing for blood in stool. Follow the package directions.

Percutaneous liver biopsy
A percutaneous liver biopsy involves the needle aspiration of a core of liver tissue for histologic analysis. It’s done under local or general anesthesia. This biopsy can detect hepatic disorders and can confirm cancer if ultrasonography, computed tomography (CT) scans, and radionuclide studies have proved inconclusive.

What’s your profile?

Focus topic: Gastrointestinal disorders

Because many patients with hepatic disorders have clotting defects, a clotting profile (prothrombin time [PT], partial thromboplastin time [PTT]) along with type and crossmatching should precede liver biopsy.
In a liver biopsy, a Menghini needle attached to a 5-ml syringe containing normal saline solution is introduced through the chest wall and intercostal space. Negative pressure is created in the syringe. The needle is then pushed rapidly into the liver and pulled out of the body entirely to obtain a tissue specimen.

Nursing considerations
• Tell the patient to restrict food and fluids for at least 4 hours before the test.
• Explain the testing procedure to the patient:
– He will be awake during the test and, although the test is uncomfortable, medication is available to help him relax.
– The doctor will drape and clean an area on his abdomen. Then he’ll receive a local anesthetic, which may sting and cause brief discomfort.
– He’ll be instructed how and when to hold his breath and to lie still as the doctor inserts the biopsy needle into the liver.
– The needle may cause a sensation of pressure and some discomfort in the right upper back but will remain in his liver for only a few seconds.

When it’s all over

Focus topic: Gastrointestinal disorders

After the procedure:

  • The patient must remain in bed on his right side for at least 2 hours and maintain bed rest for 24 hours.
  • The patient may experience discomfort for several hours and may take ibuprofen (Motrin) but not aspirin.
  • Let the patient know that he may resume his normal diet.
  • Watch for bleeding and symptoms of bile peritonitis — tenderness and rigidity around the biopsy site.
  • Be alert for signs and symptoms of a pneumothorax, such as rising respiratory rate, depressed breath sounds, dyspnea, persistent shoulder pain, and pleuritic chest pain. Report these complications promptly.
  • Apply a gauze dressing to the puncture site. Check the dressing frequently, whenever you check vital signs. Reinforce or apply a pressure dressing if needed.
  • Maintain the patient in a right side-lying position for at least 2 hours because the pressure will enhance coagulation at the site.
  • Monitor urine output for at least 24 hours and watch for hematuria, which may indicate bladder trauma.

Peritoneal fluid analysis
The peritoneal fluid analysis series includes examination of gross appearance, erythrocyte and leukocyte counts, cytologic studies, microbiological studies for bacteria and fungi, and determinations of protein, glucose, amylase, ammonia, and alkaline phosphatase levels. A sample of peritoneal fluid is obtained by paracentesis, which involves inserting a trocar and cannula through the abdominal wall while the patient is under a local anesthetic. If the sample of fluid is being removed for therapeutic purposes, the cannula can be connected to a drainage system.

Nursing considerations
• Before the procedure, have the patient empty his bladder.
• Observe the patient for dizziness, pallor, perspiration, and increased anxiety.
• Check the site for peritoneal fluid leakage.

Shocking signs

Focus topic: Gastrointestinal disorders

• Watch for signs of hemorrhage, shock, and increasing pain and abdominal tenderness. These signs may indicate a perforated intestine or, depending on the site of the paracentesis, puncture of the inferior epigastric artery, hematoma of the anterior cecal wall, or rupture of the iliac vein or bladder.

Urine tests
Urinalysis provides valuable information about hepatic and biliary function. Urinary bilirubin and urobilinogen tests are commonly used to evaluate liver function.

The name’s Rubin, Billy Rubin

Focus topic: Gastrointestinal disorders

Bilirubin results from the breakdown of the heme fraction of hemoglobin. In the liver, free bilirubin conjugates with glucuronic acid, which allows the glomeruli to filter bilirubin (unconjugated bilirubin isn’t filtered). Bilirubin is normally excreted in bile as its principal pigment, but it also occurs abnormally in urine. Conjugated bilirubin appears in urine when serum bilirubin levels rise — as in biliary tract obstruction or hepatocellular damage — and is accompanied by jaundice.

Formed in the intestine by bacterial action on conjugated bilirubin, urobilinogen is primarily excreted in stool, producing its characteristic brown color. A small amount is reabsorbed by the portal system and is mainly re-excreted in bile, although the kidneys also excrete some. As a result, elevated urine urobilinogen levels may be an early indication of hepatic damage. In biliary obstruction, urine urobilinogen levels decline.

Nursing considerations
• Collect a freshly voided random urine specimen in the container provided.

No time to lose

Focus topic: Gastrointestinal disorders

  • You can analyze bilirubin at the patient’s bedside using dip strips. Wait 20 seconds before interpreting the color change on the dip strip. Bilirubin must be tested within 30 minutes, before it disintegrates. If it’s to be tested in the laboratory, send it immediately and record the collection time on the patient’s chart.
  • For urobilinogen, obtain a random specimen and send it to the laboratory immediately; it, too, must be tested within 30 minutes, before the sample deteriorates.

Gastrointestinal disorders: Nuclear imaging and ultrasonography

Focus topic: Gastrointestinal disorders

Nuclear imaging methods, which include liver-spleen scanning and magnetic resonance imaging (MRI), analyze concentrations of injected or ingested radiopaque substances to enhance visual evaluation of possible disease processes. Nuclear imaging methods can study the liver, spleen, and other abdominal organs.
Ultrasonography creates images of internal organs, such as the gallbladder and liver. Gas-filled structures, such as the intestines, can’t be seen with this technique.

Liver-spleen scan
In a liver-spleen scan, a scanner or gamma camera records the distribution of radioactivity within the liver and spleen after I.V. injection of a radioactive colloid. Most of this colloid is taken up by Kupffer’s cells in the liver, while smaller amounts lodge in the spleen and bone marrow. By registering the extent of this absorption, the imaging device detects such abnormalities as tumors, cysts, and abscesses. Because the test demonstrates disease nonspecifically (as an area that fails to take up the colloid, or a cold spot), test results usually require confirmation by ultrasonography, CT scan, gallium scan, or biopsy.

Nursing considerations
• Explain the testing procedure to the patient:
– This test examines the liver and spleen through pictures taken with a special scanner or camera.
– The patient will receive an injection of a radioactive substance (technetium-99m) through an I.V. line in his hand or arm to allow better visualization of the liver and spleen. The injection contains only trace amounts of radioactivity, and he won’t be radioactive after the test.
– He should immediately report any adverse reactions, such as flushing, fever, light-headedness, or difficulty breathing.
– If the test uses a rectilinear scanner, he’ll hear a soft, irregular clicking noise as the scanner moves across his abdomen.
– If the test uses a gamma camera, the patient will feel the camera lightly touch his abdomen. He should lie still, relax, and breathe normally. He may be asked to hold his breath briefly to ensure good-quality pictures.

MRI
Used in imaging the liver and abdominal organs, MRI generates an image by energizing protons into a strong magnetic field. Radio waves emitted as protons return to their former equilibrium state and are recorded. MRI transmits no ionizing radiation during the scan. One disadvantage of the process is the closed, tube like space that’s required for the scan, although newer MRI centers offer a less confining “open-MRI” scan. Patients with metal or implanted devices such as pacemakers can’t undergo this test because of the strong magnetic field it generates. MRI is useful in evaluating liver disease to help characterize tumors, masses, or cysts found on previous studies.

Nursing considerations
• Explain the testing procedure to the patient:
– He must lie still during the procedure, which may last from 30 to 90 minutes.
– He must remove any metal, such as jewelry, before the procedure.
– If he becomes claustrophobic during the test, he may be given mild sedation.

Ultrasonography
Ultrasonography uses a focused beam of high-frequency sound waves to create echoes, which then appear as images on a monitor. Echoes vary with tissue density. The test helps differentiate between obstructive and nonobstructive jaundice and diagnoses cholelithiasis, cholecystitis, and certain metastases and hematomas.

Spotlight on cold spots

Focus topic: Gastrointestinal disorders

When used with liver-spleen scanning, it can clarify the nature of cold spots, such as tumors, abscesses, and cysts. The technique also helps diagnose pancreatitis, pseudocysts, pancreatic cancer, ascites, and splenomegaly.

Nursing considerations
• If the patient is undergoing pelvic ultrasonography, he’ll need a full bladder; therefore, he must drink three or four glasses of water before the test and must avoid urinating until after the test.
• For gallbladder evaluation, tell the patient that he shouldn’t eat solid food for 12 hours before the test.
• For pancreas, liver, or spleen evaluation, tell the patient that he should fast for 8 hours before the test.
• If the patient is undergoing a barium enema or an upper GI series, make sure it occurs after abdominal ultrasonography because sound waves can’t penetrate barium.

Gastrointestinal disorders: Radiographic tests

Focus topic: Gastrointestinal disorders

Radiographic tests include abdominal X-rays, CT scans, various contrast medium studies, and virtual colonoscopy.

Abdominal X-rays
An abdominal X-ray, also called flat plate of the abdomen or kidney-ureter-bladder radiography, helps detect and evaluate tumors, kidney stones, abnormal gas collection, and other abdominal disorders. The test consists of two plates: one taken with the patient supine and the other taken while he stands. On X-ray, air appears black, adipose tissue appears gray, and bone appears white.

Compare and contrast

Focus topic: Gastrointestinal disorders

Although a routine X-ray won’t reveal most abdominal organs, it will show the contrast between air and fluid. For example, intestinal blockage traps large amounts of detectable fluids and air inside organs. When an intestinal wall tears, air leaks into the abdomen and becomes visible on X-ray.

Nursing considerations
• Radiography requires no special pretest or posttest care. Explain the procedure to the patient.
• X-ray interpretation involves locating normal anatomic structures, discerning any abnormal images, and correlating findings with assessment data.

CT scan
In CT scanning, a computer translates the action of multiple X-ray beams into three-dimensional oscilloscope images of the biliary tract, liver, and pancreas. The test can be done with or without a contrast medium, but contrast is preferred (unless the patient is allergic to contrast medium). This test:
• helps distinguish between obstructive and nonobstructive jaundice
• identifies abscesses, cysts, hematomas, tumors, and pseudocysts
• can help evaluate the cause of weight loss
• detects occult malignancy
• can help diagnose and evaluate pancreatitis.

Nursing considerations
• Tell the patient to restrict food and fluids after midnight before the test but to continue any drug regimen, as ordered.
• Explain that the patient should lie still, relax, breathe normally, and remain quiet during the test because movement blurs the X-ray picture and prolongs the test.
• If the practitioner orders an I.V. contrast medium, the patient may experience discomfort from the needle puncture and a localized feeling of warmth on injection.
• If the patient has a seafood or dye allergy, a pretest preparation kit containing prednisone, cimetidine, and diphenhydramine may be given to him. He should immediately report any adverse reactions, such as nausea, vomiting, dizziness, headache, and urticaria (hives). Assure him that reactions are rare.
• Explain that the patient may resume his normal diet after the test.

Contrast radiography
Some X-ray tests require contrast media to more accurately assess the GI system because the media accentuate differences among densities of air, fat, soft tissue, and bone. These tests include barium enema, barium swallow test, cholangiography, endoscopic retrograde cholangiopancreatography (ERCP), small-bowel series and enema, and upper GI series.

Barium below, barium above

Focus topic: Gastrointestinal disorders

The barium enema is most commonly used to evaluate suspected lower intestinal disorders. It helps diagnose inflammatory disorders, colorectal cancer, polyps, diverticula, and large-intestine structural changes such as intussusception. The barium swallow test allows examination of the pharynx and esophagus to detect strictures, ulcers, tumors, polyps, diverticula, hiatal hernia, esophageal webs, gastroesophageal reflux disease (GERD), motility disorders and, sometimes, achalasia.

Cholangiography clues

Focus topic: Gastrointestinal disorders

In cholangiography (percutaneous and postoperative), a contrast agent is injected into the biliary tree through a flexible needle. In percutaneous transhepatic cholangiography (PTHC), a radiopaque dye is injected directly into the liver through the eighth or ninth midaxillary intercostal space. If done postoperatively, the dye is injected by way of a T tube. In an oral cholangiogram, the patient is given the contrast medium by mouth. These tests are used to determine the cause of upper abdominal pain that persists after cholecystectomy, to evaluate jaundice, and to determine the location, extent and, usually, the cause of mechanical obstructions.

Down endoscope

Focus topic: Gastrointestinal disorders

In ERCP, the doctor passes an endoscope into the duodenum and injects dye through a cannula inserted into the ampulla of Vater. This test helps to determine the cause of jaundice; evaluate tumors and inflammation of the pancreas, gallbladder, or liver; and locate obstructions in the pancreatic duct and hepatobiliary tree.

Shorter series or better distender?

Focus topic: Gastrointestinal disorders

Results of a small-bowel series or enema, which follow the contrast agent through the small intestine, may suggest sprue, obstruction, motility disorders, malabsorption syndrome, Hodgkin’s disease, lymphosarcoma, ischemia, bleeding, inflammation, or Crohn’s disease of the small intestine. Although longer and more uncomfortable than the small-bowel series, the enema study better distends the bowel, making lesion identification easier.

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I spy with an upper GI

Focus topic: Gastrointestinal disorders

In an upper GI series, the practitioner follows the barium’s passage from the esophagus to the stomach. Usually combined with a small-bowel series, the upper GI series helps diagnose gastritis, cancer, hiatal hernia, diverticula, strictures, and (most commonly) gastric and duodenal ulcers. It may also suggest motility disorders.

Nursing considerations
• Tell the patient where and when the test will take place.
• Explain that the test will take only 30 to 40 minutes for a barium swallow or enema but can take up to 6 hours for an upper GI or small-bowel series.
• Instruct the patient to maintain a low-residue diet for 2 to 3 days and restrict food, fluids, and smoking after midnight before the test. He’ll receive a clear liquid diet for 12 to 24 hours before the test. As ordered, he’s to stop taking medications for up to 24 hours before the test.
• Unless he’s undergoing a barium swallow test, the patient will receive a laxative the afternoon before the test and up to three cleaning enemas the evening before or the morning of the test. Explain that the presence of food or fluid may obscure details of the structures being studied.
• Let the patient having a barium enema know that he will lie on his left side while the practitioner inserts a small, lubricated tube into his rectum. Instruct the patient to keep his anal sphincter tightly contracted against the tube to hold it in position and help prevent barium leakage. Stress the importance of retaining the barium.

Eliminating barium

Focus topic: Gastrointestinal disorders

• After the test, the patient may resume his normal diet and medication as ordered, and will receive a laxative to help expel the barium. Stress the importance of barium elimination because retained barium may harden, causing obstruction or impaction. The barium will lighten the color of his stools for 24 to 72 hours after the test.
• If the patient is having an oral cholangiogram, explain that, if ordered, he’ll eat a meal containing fat at noon the day before the test and a fat-free meal that evening. After the evening meal, he can have only water but should continue any drug regimen, as ordered.
• Tell the patient that he’ll be given a cleaning enema and, 2 to 3 hours before the test, he’ll be asked to swallow six tablets, one at a time, at 5-minute intervals. The enema and tablets help outline the gallbladder on the X-ray film. He should immediately report any adverse reactions to the tablets, such as diarrhea, nausea, vomiting, abdominal cramps, and dysuria.
• Explain that he’ll be asked to swallow barium several times during the test. Describe barium’s thick consistency and chalky taste.

Virtual colonoscopy
Virtual colonoscopy is a nonsurgical approach to evaluate the colon. A soft-tipped catheter introduces air into the colon while a three-dimensional CT scan is performed. The scan takes about 10 minutes. Images are assembled in a computer program that can be viewed on a screen. This test may be useful for the patient who refuses traditional colonoscopy.

Nursing considerations
• Tell the patient that he may feel discomfort when air is introduced into the colon.
• Instruct the patient to remain still while images are taken.
• Tell the patient that he’ll have no restrictions after the test but that he may feel bloated from the air introduced into his colon.

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