Diagnostics Chapt 43 Flashcards
what do you look for in stool tests
consistency, color, and occult (not visible) blood
What else can be found from a stool test
Urobilinogen, fecal fat, parasites, pathogens, food residues, C Diff
How are stool samples collected?
on a random basis unless a quantitative study (ex. fecal fat, urobilinogen) is to be performed.
When should stool samples be sent to the lab?
random specimens should be sent promptly to the lab for analysis. Quantitative 24-72 hour collections must be kept refrigerated until transported to the lab.
What is the most commonly performed stool test?
Fecal Occult Blood Testing (FOBT)
What is FOBT used for
it can be useful for the initial screening of several disorders. Most frequently used for early cancer detection.
Where can a FOBT test be collected?
at the bedside, in the laboratory, or at home
When should a FOBT NOT be performed
if there is hemorrhoidal bleeding.
What is a fecal immunologic test (FIT)
uses monoclonal or polyclonal antibodies to detect globin protein in human hemoglobin
Are there dietary restrictions prior to submitting a FIT test?
No dietary restrictions
Hematoporphyrin is a test that detects _____
are dietary restrictions necessary?
the broadest range of blood derivatives.
A strict dietary protocol is essential
what is stool DNA used for?
to detect certain DNA related to colon cancer
Breath tests determine the amount of ____ expelled in the breath after it has been produced in the ____ and absorbed into the blood
hydrogen, colon
breath tests aid in the diagnosis of
bacterial overgrowth in the intestine and short bowel syndrome
Urea breath tests determine the presence of
Helicobacter Polyri (lives in the lining of the stomach and causes peptic ulcer disease)
How the urea breath sample is collected?
The patient ingests a capsule of carbon-labeled urea, a breath sample is obtained 10-20 mins later
Prior to urea breath testing the patient should avoid
antibiotics or bismuth for 1 month before the test, sucralfate and omeprazole for 1 week before the test, and cimetidine, famotidine, and ranitidine for 24 hours before the test.
What is an ultrasound
noninvasive diagnostic technique in which high-frequency sound waves are passed into internal body structures
What are the advantages of ultrasounds?
absence of ionizing radiation, no noticeable side effects relatively low costs, and almost immediate results
What is endoscopic ultranonography
is a specialized enteroscopic procedure that aids in the diagnosis of GI disorders by providing direct imaging of a target area.
Nursing Interventions for ultrasounds
The patient is instructed to fast for 8-12 hours before testing to decrease the amount of gas in the bowel.
If gall bladder studies are being performed the patient should eat a fat-free meal the evening before the test
Barium studies should be done after the ultrasound
Patients that receive sedation should be observed for an hour after
What is an Upper GI Tract study used for?
it can detect or exclude anatomical functional disorders of the upper GI organs or sphincter. Aids in diagnosis of ulcers, varices, tumors, regional enteritis, and malabsorption syndromes.
There are two variations of the upper GI tract study
double-contrast studies and enteroclysis
what is a double contrast study?
The patient is given barium to outline the stomach and esophageal wall. Then tablets that release CO2 in water are given. This technique shows the esophagus and stomach in finer detail. Permitting signs of early superficial neoplasms to be noted.
What is enteroclysis?
very detailed double contrast study of the entire small intestine that involves a continuous infusion of 500-1000 mL of a thin barium sulfate solution, after this methylcellulose is infused through the tube.
How long does enteroclysis last?
can take up to 6 hours and its very uncomfortable.
What is enteroclysis used for?
aids in the diagnosis of partial bowel obstructure or diverticula.
Nursing interventions for upper GI tract study
clear liquid diet, NPO from midnight the night before the study.
Meds are withheld on the morning of the exam and resumed that evening
when an insulin pt is NPO their insulin should be adjusted
What is the most effective bowel cleansing preparatory agent?
Polyethylene glycol (PEG)
upper GI tract study follow up care
ensure the patient has eliminated most of the ingested barium. Fluids may be increased to facilitate evacuation of stool and barium.
Lower GI tract study
Barium enema is used to detect the presence of polyps, tumors, or other lesions of the large intestine and show any anatomic abnormalities or malfunctioning of the bowel
How long does the lower GI tract study take?
15- 30 minutes (during which xrays are obtained)
What is a double-contrast or air contrast barium enema?
involves the installation of a thicker barium solution, followed by the installation of air. The pt may feel cramping or discomfort.
When is a water-soluble iodinated contrast agent used?
if active inflammatory disease, fistulas, or perforation of the colon is suspected. The procedure is the same as the barium enema
PATIENT MUST BE ASSESSED FOR IODINE OR CONTRAST AGENT ALLERGY
Preparation for a lower GI tract study
emptying and cleaning of the lower bowel
low residue diet 1-2 days before the test
clear liquid diet
laxative the evening before the test
NPO after midnight
cleansing enemas until returns are clear the following morning.
When are enemas contraindicated?
- if the patient has active inflammatory disease of the colon.
- patients with signs of perforation or obstruction
- Active GI bleeding
What is a CT scan used for?
to detect inflammatory conditions in the colon, such as appendicitis, diverticulitis, regional enteritis, and ulcerative colitis, as well as evaluating the abdomen for diseases of the liver, spleen, kidney, pancreas, and pelvic organs, and structural abnormalities of the abdominal wall.
Risks associated with a CT scan
allergic reactions and acute kidney injury
Determine allergies to contrast agents, iodine, shellfish before the test.
What can you give the patient to prevent kidney injury
administration of IV sodium bicarbonate 1 hour before and 6 hours after IV contrast and oral N-acetylcysteine before or after the study
what is fibroscopy/esophagogastroduodenoscopy
the gastroenterologist views the GI tract through a viewing lens and can obtain images through the scope to document findings
what is PillCam ESO or capsule endoscopy
requires the patient to swallow a capsule that travels by peristalsis through the small intestines. The capsule contains a camera that transmits digital images of the GI mucosa to a data recorder. The patient passes the capsule in 24 hours
what is Endoscopic retrograde cholangiopancreatography (ERCP) used for?
It is helpful in evaluating jaundice, pancreatitis, pancreatic tumors, common bile duct stones, and biliary tract disease.
ASSOCIATED WITH POSTPROCEDURE PANCREATITIS
What is therapeutic endoscopy used for?
to remove common bile duct stones, dilate strictures, and treat gastric bleeding and esophageal varices.
Nursing interventions for endoscopy
pt should be NPO for 8 hours prior to the exam. The patient is given a local anesthetic before the introduction of the endoscope.
What anesthetic is given to the patient during an endoscopy
Midazolam (Versed) provides moderate sedation, with loss of the gag reflex and relieves anxiety.
Why is Atropine given to patients?
to reduce secretions
Why is glucagon given to patients?
to relax smooth muscle
What position is the patient placed in during an endoscopy?
Left lateral- to facilitate clearance of pulmonary secretions and provide smooth entry of the scope
What is a colonoscopy used for?
diagnostic aid and screening device. Most frequently used for cancer screening and for surveillance in patients with previous colon cancer or polyps
What are other uses of a colonoscopy?
for the evaluation of patients with diarrhea, occult bleeding, or anemia; further study of abnormalities detected on barium enema; and diagnosis, clarification, and determination of the extent of inflammatory or other bowel disease.
What position is a patient placed in during a colonoscopy?
left side with the legs drawn up towards the chest.
Complications of a colonoscopy
cardiac dysrhytmias, and respiratory depression from the meds that are given.
Vasovagal reactions
circulatory overload
hypotension
How long does a colonoscopy take?
about an hour
What is the preparation for a colonoscopy?
the doctor may prescribe a laxative for two nights before the exam and a fleet or saline enema until the return is clear the morning of the test.
Clear liquid diet starting at noon the day before the procedure
What is the current recommendation for colonoscopy preparation
2-L PEG split-dose regimen in low or no risk patients, and 4-L split-dose with sodium picosulfate plus bisacodyl in patients with comorbidities such as diabetes, chronic constipation, or current hx of opioid use, or with a hx of problematic colonoscopies.
Then the pt ingests the lavage solution orally at intervals over 3-4 hours
lavage solution is contraindicated in
patients with intestinal obstruction or Inflammatory bowel diease
Side effects of electrolyte solutions
nausea, bloating, cramping, abdominal fullness, fluid and electrolyte imbalance, and hypothermia
Why is it important to monitor older adults during a bowel prep
b/c their physiologic ability to compensate for fluid loss is diminished.
The nurse instructs all patients to do what while undergoing bowel cleaning
maintain adequate fluid, electrolyte, and caloric intake
Colonoscopy cannot be performed if there is
a suspected or documented colon perforation, acute severe diverticulitis, or fulminant colitis.
Patients with prosthetic heart valves or a hx of endocarditis require____ antibiotics before the procedure
prophylactic
Does a colonoscopy require informed consent?
YES!!
During a colonoscopy, the patient should be monitored for
changes in oxygen saturation, vital signs, color and temperature of the skin, level of consciousness, abdominal distention, vagal response, and pain intensity
After a colonoscopy, the patient should be
kept on bed rest until fully awake, monitored for signs and symptoms of bowel perforation (rectal bleeding, abdominal pain, distention, fever, or focal peritoneal signs).
what is an endoscopy used for?
used to evaluate chronic diarrhea, fecal incontinence, ischemic colitis, lower GI hemorrhage and to observe for ulcerations, fissures, abscesses, tumors, polyps, or other pathologic processes.
Preparation for an endoscopy
limited bowel prep is necessary.
warm tap water or fleet enema until returns are clear
Dietary restrictions usually not necessary
What does the nurse monitor during an endoscopy?
vital signs, skin color, temperature, pain tolerance and vagal response.
What does the nurse monitor after the endoscopy procedure
rectal bleeding and signs of intestinal perforation
