It is the endoscopic examination of the colon and the distal part of the small bowel with a CCD camera or a fiber optic camera on a flexible tube passed through the anus. It may provide a visual diagnosis and grants the opportunity for biopsy or removal of suspected lesions.IT differs from sigmoidoscopy in allowing an examination of the entire colon while sigmoidoscopy allows to vizualize only the final two feet of the colon.
INDICATION:
1. Gastrointestinal hemorrhage
2. Suspicion of malignancy
3. Inflammatory bowel disease (chron's disease & ulcerative colitis)
4. Unexplained drop in hematocrit (In anemia)
5. Positive feacal occult blood test
6. Unexplained changes in bowel habit
7. If any abnormality found on colon x- ray or a CT scan
PROCEDURE:
Bowel preparation
* The colon must be free of solid matter for the test to be performed properly
* For one to three days, the patient is required to follow a low fiber or clear-liquid only diet
* Patient should be well hydrated
* The patient should be given appropriate Colonic Cleansing
* Most medications should be continued as usual, but some may interfere with the examination.
* If the patient is on Aspirin products, blood thinners (Coumadin, etc.), arthritis medications, insulin, and iron preparations that may require special instructions
## Regimens For Colonic Cleansing Before Colonoscopy:-
a.Diet - Dietary modifications alone, such as a clear liquid diet, are inadequate for colonoscopy
b.Enemas - Used in patients who present to endoscopy with a poor distal colon preparation and in patients with a defunctionalized distal colon
c.High-Volume - Gut Lavage such as mannitol
d.Rectal Pulsed Irrigation - Rectal pulsed irrigation administered immediately before the procedure combined with magnesium citrate given the evening before the procedure is a reasonable alternative to full-volume (4-liters) polyethylene glycol (PEG) in those individuals who cannot tolerate per oral administration of PEG
e.PEG (Electrolyte Lavage Solution) -
faster, more effective, and better-tolerated method
PEG is safer than osmotic laxatives/sodium phosphate (NaP) for patients with electrolyte or fluid imbalances, such as renal or liver insufficiency, congestive heart failure, or liver failure
PEG regimens (2–3 liters given the night before the colonoscopy and 1–2 liters on the morning of procedure)
f.Aqueous Sodium Phosphate - An equal alternative to PEG solutions except for pediatric and elderly patients, patients with bowel obstruction, and other structural intestinal disorders, gut dysmotility, renal failure, congestive heart failure, or liver failure
-Contraindications of NaP
* In patients younger than five years of age
* Those with serum electrolyte imbalances
* Advanced hepatic dysfunction
* Acute and chronic renal failure
* Recent myocardial infarction, unstable angina, congestive heart failure
* Ileus, malabsorption, and ascites
IN THE PROCEDURE:
* It usually takes 15 to 60 minutes
* The patient is often given sedation intravenously such as fentanyl or
midazolam
* Monitoring the Vital parameters
* Patients will be lying on their left side or back
* First step is usually a digital rectal examination, to examine the tone of the
sphincter and to determine if preparation has been adequate
* Then endoscope is passed to visualize the entire colon
* Suspicious lesions may be cauterized, treated with laser light or cut with an
electric wire for purposes of biopsy or complete removal polypectomy
* Medication can be injected, e.g. to control bleeding lesions
COMPLICATIONS:
1. Gastrointestinal perforation, which is life-threatening
2. Bleeding
3. Splenic rupture
4. On very rare occasions, intracolonic explosion