Norm of Sigmoidoscopy
Usage of Sigmoidoscopy
Identify bowel obstruction, carcinoma of sigmoid colon, celiac sprue, colitis, Crohn's disease, diverticulitis, diverticulosis; help diagnose causes of malabsorption.
Description of Sigmoidoscopy
Sigmoidoscopy is the endoscopic visualization of the interior space and walls of the sigmoid colon, using a sigmoidoscope. A sigmoidoscope is a 50-cm fiberoptic tube with a lighted mirror lens system that illuminates the sigmoid colon for visualization. A rigid sigmoidoscope is rarely used, because of the degree of discomfort it causes. The most common method for this procedure is a flexible sigmoidoscopy, in which a short, flexible tube with a light source is inserted through the rectum and advanced to the sigmoid colon. Because flexible sigmoidoscopy examines only the lower one third of the colon, it cannot completely rule out colon cancer. However, it has been shown to identify 50%–70% of advanced colorectal neoplasms and thus is considered a cost-effective test for screening. The American Cancer Society recommends screening sigmoidoscopy every 5 years for all adults >50, followed by a colonoscopy in those with positive results.
Professional Considerations of Sigmoidoscopy
Consent form IS required.
Bowel perforation (rare), peritonitis, hemorrhage, vasovagal reaction.
Anorectal fistula, diverticulitis, paralytic ileus, third-trimester pregnancy. Sedatives are contraindicated in clients with central nervous system depression.
- See Client and Family Teaching.
- Obtain sterile specimen containers if a biopsy is planned.
- The client should disrobe below the waist or wear a gown.
- Just before beginning the procedure, take a “time out” to verify the correct client, procedure, and site.
- The client is placed in the left lateral position.
- Monitor blood pressure, heart rate, and oxygen saturation rate by pulse oximeter before analgesic and sedative are given and then every 5 minutes during the procedure.
- An analgesic and/or a sedative may be administered. Monitor respiratory status continually after sedation.
- The sigmoidoscope is lubricated and inserted into the anus and rectum and then slowly advanced into the sigmoid colon. Insufflation occurs to aid in visualization. However, insufflation of CO2 rather than air reduces abdominal pain and bowel distention after colonoscopy.
- During the procedure, biopsy specimens and photographs may be taken, and suction is used to remove excess secretions.
- Assess for side effects of the sedative: hypotension, depressed respirations, and bradycardia.
- Continue the assessment of the respiratory status. If deep sedation was used, follow institutional protocol for post-sedation monitoring. Typical monitoring includes continuous ECG monitoring and pulse oximetry, with continual assessments (every 5–15 minutes) of airway, vital signs, and neurologic status until the client is lying quietly awake, is breathing independently, and responds to commands spoken in a normal tone.
Client and Family Teaching
- This test is performed to evaluate the colon for several different disorders.
- Consume a full liquid diet the evening before the test.
- Laxatives may be prescribed to be administered the night before the test with or without an enema or suppository 1 hour before the test, except in pregnant women. Magnesium citrate and a Fleet enema also produce excellent results.
- The urge to defecate as the sigmoidoscope is inserted into the rectum is normal.
- The procedure takes approximately 30 minutes.
- Resume normal activities and diet as soon as you feel ready.
- Call a physician if your temperature is higher than 101 degrees F (38.3 degrees C), or if you have trouble breathing or experience stomach pain, nausea, or bright-red rectal bleeding.
Factors That Affect Results
- Retained barium from previous studies makes visualization impossible.
- Fixation of the bowel from previous radiation therapy or surgery may inhibit the passage of the sigmoidoscope.
- Older clients and female clients have a higher incidence of incomplete exams and inadequate sigmoidoscopies, because of failure to achieve at least a depth of insertion of 40 cm. The rate of complete exams can be increased by use of sedation, analgesia, and/or distraction during the examination.
- Women more than men fail to comply with recommendations to have this procedure done for cancer screening. A major contributor to this decision is a low perceived risk of bowel cancer because of current health/symptom status, and lack of having a family history of colorectal cancer.