GI procedures

Question 1

Nasogastric Intubation

Answer 1

Passage of a tube through the nares, esophagus and into the stomach

Indications:
Evacuate blood 
Decompress 
Remove toxic substances
Provide enteral feedings

Required equipment
Nasogastric tube
Lubricant
Cup of water with a straw
Tape
Large syringe

Question 2

Nasogastric intubation complications and contraindications

Answer 2

Complications
Bleeding	
Aspiration
Tracheal intubation
Erosion of naris (Long term)
Pharyngeal/nasal perforation

Contraindications
Facial trauma 
Basilar skull fracture
Bilateral nasal obstruction  
Recent nasal, pharyngeal,  esophageal or gastric surgery 
Bleeding diathesis

Question 3

Types of nasogastric tubes

Answer 3

The Levin tube is a one-lumen nasogastric tube. The Levin tube is usually made of PVC with several drainage holes near the gastric end of the tube. There are graduated markings on the lumen so that you can see how far you have inserted the tube into the patient.

The Salem-Sump tube is a two-lumen tube. It has a drainage lumen and a smaller secondary tube that is open to the atmosphere. The second lumen allows for continuous suction and prevents gastric mucosa from being aspirated into the tube.

Question 4

Esophagogastroduodenoscopy (EGD)

Answer 4

Esophagogastroduodenoscopy (EGD) is a procedure during which a small flexible endoscope is introduced through the mouth (or with smaller caliber endoscopes, through the nose) and advanced through the pharynx, esophagus, stomach, and duodenum. EGD is used for both diagnostic procedures and therapeutic procedures.
Other instruments can be passed through the endoscope to perform additional procedures. For example, a biopsy can be done in which a small tissue specimen is obtained for microscopic analysis. A polyp or tumor can be removed using a thin wire snare and electrocautery.

Question 5

EGD indications

Answer 5

Diagnostic evaluation for signs or symptoms suggestive of upper GI disease, e.g. dyspepsia, dysphagia, noncardiac chest pain, recurrent emesis
Surveillance for upper GI cancer in high-risk settings, e.g. Barrett’s esophagus, polyposis syndromes
Biopsy for known or suggested upper GI disease, e.g. malabsorption syndromes, neoplasms, infections
Therapeutic intervention e.g. retrieval of foreign bodies, control of hemorrhage, dilatation or stenting of stricture, excision of neoplasms, gastrostomy tube placement

Question 6

egd contraindications

Answer 6

Absolute contraindications
Known or suspected perforation
Medically unstable patients
Obstruction

Relative contraindications:  
Anticoagulation 
Pharyngeal diverticulum 
Recent head or neck surgery
Esophageal stricture

Question 7

EGD complications

Answer 7

Bleeding 
Infection 
Perforation
Vocal cord injury
Pharyngeal irritation 
Cardiopulmonary problems  ** Cardiopulmonary events make up 50% of all major complications; such events are usually caused by the medications used for conscious sedation.

Question 8

The following increase the risk of esophagitis:

Answer 8

• Alcohol use
• Cigarette smoking
• Surgery or radiation to the chest (for example, treatment for lung cancer)
• Taking certain medications, i.e. tetracycline, doxycycline, vitamin C and aspirin
• Prolonged vomiting
• Persons with weakened immune systems due to HIV and certain medications (such as corticosteroids)
• Fungi or viruses

Question 9

Barrett’s Esophagitis

Answer 9

Esophageal adaption from chronic acid reflux

• Columnar epithelium replaces the squamous epithelium of the esophagus
• Premalignant condition
• Malignant transformation is highest in Caucasian men greater than 50 with more than 5 years of symptoms

Question 10

Esophageal Cancer

Answer 10

Squamous cell in the proximal and mid esophagus, adenocarcinoma in the distal esophagus
20-30 times higher rate of occurrence in China
Risk Factors
Smoking
Ethanol use
High fat/low protein diet
GERD/Barrett’s esophagitis
Most common sites of metastasis are lungs, pleura, liver, stomach, peritoneum, kidneys and the adrenal gland.

Question 11

Gastric Ulcer

Answer 11

Usually caused by disruption of the gastric mucosal barrier:

• Helicobacter pylori infection
• NSAIDS/aspirin
• The most common site is the angular incisura, followed by the lesser curvature and the antrum.

Question 12

Gastric Cancer

Answer 12

Risk Factors:
H. pylori
Salty and smoked foods
Chronic gastritis
Smoking
Diet low in fruits and vegetables
Blood type A

Once 2nd most common cancer in U.S., now 14th

Primarily adenocarcinoma

In Japan, it remains the most common type of cancer among men
In western countries, the most common sites of gastric cancer are the proximal lesser curvature, cardia, and GE junction
In Asia, distal locations in the stomach are more common

Question 13

distinguishing factor: upper GI to lower GI

Answer 13

ligament of treitz

Question 14

Sigmoidoscopy

Answer 14

Flexible sigmoidoscopy is a procedure where the rectum and the lower (sigmoid) colon is examined under direct visualization. The flexible sigmoidoscope is a flexible tube 60 cm long and about 1.25 cm in diameter. It is inserted through the anus and advanced slowly into the rectum and sigmoid colon.

Question 15

Sigmoidoscopy indications

Answer 15

Colorectal cancer screening
Preoperative evaluation prior to anorectal surgery
Surveillance of previously diagnosed (treated or untreated) malignancy (or polyp with high-grade dysplasia) in the rectum or sigmoid colon
Local treatment of ailments such as radiation proctitis
Removal of rectal foreign bodies
To perform therapeutic procedures such as endoluminal stent placement for strictures, balloon dilation, or decompression with placement of a decompression tube
Hematochezia requiring hemostasis

Question 16

Sigmoidoscopy contraindications

Answer 16

Absolute contraindications 
Bowel perforation
Acute diverticulitis
Active peritonitis
Fulminant colitis
Cardiopulmonary instability

Relative contraindications
Lack of informed consent (except in emergencies)
Lack of patient cooperation
Lack of good bowel preparation

Question 17

Sigmoidoscopy complications

Answer 17

Pain
Bleeding
Perforation
Infection

Question 18

Colonoscopy

Answer 18

The advantage of colonoscopy over flexible sigmoidoscopy is the ability to find and remove polyps in the parts of colon that are beyond the reach of the flexible sigmoidoscope.

The patient is mildly sedated, the endoscope is inserted through the anus and advanced gently around the bends of the colon. If a polyp is encountered, a thin wire snare is used to remove it. Electrocautery (electrical heat) is applied to painlessly control any bleeding. Other tests can be performed during colonoscopy, including biopsy.

Question 19

Colonoscopy indications

Answer 19

Colorectal cancer screening in average-risk adults
Evaluation and removal of polyps
Current or previous bowel resection for colon cancer
Family history of cancer
Management of inflammatory bowel disease
Identification of acute bleeding sites
Decompression of colon

Question 20

colonoscopy contraindications

Answer 20

Absolute contraindications
Fulminant colitis
Known or suspected perforation
During early post-colectomy time period

Relative contraindications
History of radiation therapy for abdominal or pelvic cancer
History of abdominal or pelvic malignancy
Extensive adhesions from prior abdominal surgery
Bleeding dyscrasias
Anticoagulant therapy

Question 21

Colonoscopy complications

Answer 21

Bleeding 
Perforation 
Respiratory depression 
Cardiac arrythmias or ischemia 
Transient bacteremia 
Nausea/vomiting 
Ileus

Question 22

Colonoscopy/Sigmoidoscopy Preparation

Answer 22

In order to obtain accurate results, the rectum and the lower colon must be completely clean of stool. In general, this requires the use of one or two enemas prior to the procedure and may also call for a laxative and some dietary modifications. Under special circumstances, such as the presence of significant diarrhea, the preparation may be waived.

Question 23

Pedunculated Polyp

Answer 23

Pedunculated polyps are mushroom-like tissue growths that are attached to the surface of the mucous membrane by a long, thin stalk, or peduncle.

The development of pedunctulated polyps can be due to inherited or non inherited causes.

Question 24

Sessile Polyp

Answer 24

Sessile polyps sit right on the surface of the mucous membrane and do not have a stalk.

• Sessile polyps are flat.
• Generally have more malignant potential.

Question 25

Colon Cancer

Answer 25

Surface of the cancer is generally irregular and ulcerated.

-Malignant tumors often are partially or completely circumferential and if left untreated obstruct the lumen.

Question 26

• Ulcerative Colitis

Answer 26

Patients generally have more pain, cramping and rectal bleeding
Diarrhea and fever are common
On colonoscopy, characterized by ulceration, bleeding, continuous involvement and pseudopolyps
Mucosa is more friable and bleeds more easily than Crohn’s
Risk of coplon cancer rises each decade after diagnosis

Question 27

• Crohn’s Disease

Answer 27

Symptoms can occur at any point along the gastrointestinal tract
Symptoms are similar to ulcerative colitis but usually:
More cramping with diarrhea
Less bleeding
Symptoms wax and wane
On colonoscopy, characterized by inflammation, cobble-stone appearance and “skip” lesions

Question 28

ulcerative colitis vs crohn’s disease

Answer 28

crohn's:
discontinuous involvement
cobblestoning
aphthous ulcers
deep, longitudinal serpiginous ulcers
rectal sparing or segmental inflammation
anal lesions
ileocecal valve stenotic and ulcerated

ulcerative colitis:
continuous involvement
erosions/ microulcers
loss of vascular pattern
rectal involvement
ileocecal valve patulous and free of ulceration

Question 29

Virtual Colonoscopy (VC)

Answer 29

Medical imaging procedure which uses imaging and computers to produce two- and three-dimensional images of the colon from the rectum, all the way to the distal ileum.
The procedure is used to diagnose colon and bowel disease, including polyps, diverticulosis and cancer.
VC is performed via x-rays, i.e. computed tomography (CT) or magnetic resonance imaging (MRI).

Question 30

Colorectal Cancer Screening Tests

Answer 30

FOBT
Stool DNA
Sigmoidoscopy
Colonoscopy
Colonography 
DCBE
DRE

Question 31

Fecal Occult Blood Test (FOBT)

Answer 31

Advantages:
No cleansing of the colon is necessary.
Samples can be collected at home.
The cost is low compared with other colorectal cancer screening tests.
FOBT does not cause bleeding or tearing/perforation of the lining of the colon.

Disadvantages:
This test fails to detect most polyps and some cancers.
False-positive results are common. Very sensitive but not specific since the wood resin of Guaiacum trees reacts with iron
Dietary restrictions and changes, such as avoiding meat, certain vegetables, vitamin C, iron supplements, and aspirin are often recommended for several days before a guaiac FOBT.
Should be repeated three to four times prior to drawing any conclusions
Additional procedures, such as colonoscopy, may be necessary if the test indicates an abnormality.

Question 32

DNA Stool Testing

Answer 32

Cologuard
Came to market 2014, FDA approved
Recommended for screening in average-risk patients aged 50+, to repeat every three years
Colonoscopy may still be needed if test is abnormal
Does not require special bowel prep or change in diet or medication
Can be done at home
Does not require time off from work

Question 33

Sigmoidoscopy- advantages and disadvantages

Answer 33

Advantages
The test is usually quick, with few complications.
For most patients, discomfort is minimal.
In some cases, the doctor may be able to perform a biopsy and remove polyps during the test, if necessary.
Less extensive cleansing of the colon is necessary with this test than for a colonoscopy.

Disadvantages
This test allows the doctor to view only the rectum and the lower part of the colon. Any polyps in the upper part of the colon will be missed.
There is a very small risk of bleeding or tearing/ perforation of the lining of the colon.
Additional procedures, such as colonoscopy, may be necessary if the test indicates an abnormality.

Question 34

Colonoscopy

advantages and disadvantages

Answer 34

Advantages
This test allows the doctor to view the rectum and the entire colon.
The doctor can perform a biopsy and remove polyps or other abnormal tissue during the test, if necessary.

Disadvantages
This test may not detect all small polyps, nonpolypoid lesions, and cancers, but it is one of the most sensitive tests currently available.
Thorough cleansing of the colon is necessary before this test.
Some form of sedation is used in most cases.
Although uncommon, complications such as bleeding and/or tearing/perforation of the lining of the colon can occur.

Question 35

Colonography

advantages and disadvantages

Answer 35

This test allows the doctor to view the rectum and the entire colon.
The test takes only 10-15 minutes and does not require the use of anesthesia.
This is not an invasive procedure, so there is little risk of bleeding or tearing/perforation of the lining of the colon.
Still covered on most insurances, recommended to be done every five years in average risk patients age 50+.

Disadvantages
This test may not detect all small polyps, nonpolypoid lesions, and cancers.
Thorough cleansing of the colon is necessary before the test.
If a polyp or non-polypoid lesion 6 to 9 millimeters in size or larger is detected, standard colonoscopy, usually immediately after the virtual procedure, will be recommended to remove the polyp or lesion or perform a biopsy.
During the procedure the rectum is insufflated with gas for visibility, the gas is removed at the end of the procedure but patients report this is extremely uncomfortable during the procedure and takes several days to fully resolve.

Question 36

Double Contrast Barium Enema (DCBE)

advantage and disadvantages

Answer 36

Advantages
This test usually allows the doctor to view the rectum and the entire colon.
Complications are rare.
No sedation is necessary
This is still a covered screening benefit on most insurances at recommended intervals of five years.

Disadvantages
This test may not detect some small polyps and cancers.
Thorough cleansing of the colon is necessary before the test.
False-positive results are possible.
The doctor cannot perform a biopsy or remove polyps during the test.
Additional procedures are necessary if the test indicates an abnormality.

Question 37

Digital Rectal Exam (DRE)

advantages and disadvantages

Answer 37

Disadvantages
The test can detect abnormalities only in the lower part of the rectum.
Additional procedures are necessary if the test indicates an abnormality.