Flexible SigmoidoscopyFlexible Sigmoidoscopy

Scott M. Strayer, MD, MPH

Assistant Professor

University of Virginia Health System

Department of Family Medicine

Colon CancerColon Cancer

• 150,000 cases per year.

• 50,000 deaths annually.

• #2 cause of cancer mortality in non-smoking males and females.

Screening Screening RecommendationsRecommendations

• The USPSTF strongly recommends that clinicians screen men and women 50 years of age or older for colorectal cancer. (A recommendation)

• Good evidence that periodic fecal occult blood testing (FOBT) reduces mortality from colorectal cancer and fair evidence that sigmoidoscopy alone or in combination with FOBT reduces mortality. Insufficient evidence that newer screening technologies (e.g., computed tomographic colography) are effective in improving health outcomes.

Screening Screening RecommendationsRecommendations•  

• AAFP-No published standards or guidelines for low-risk patients

• ACOG-After age 50, annual FOBT (DRE should accompany pelvic examination); sigmoidoscopy every 3 to 5 years

• ACS-After age 50, yearly FOBT plus flexible sigmoidoscopy and DRE every 5 years or colonoscopy and DRE every 10 years or double-contrast barium enema and DRE every 5 to 10 years

Screening Screening RecommendationsRecommendations

• AMA-Annual FOBT beginning at age 50, and flexible sigmoidoscopy every 3 to 5 years beginning at age 50

• AGA-FOBT beginning at age 59 (frequency not specified); sigmoidoscopy every 5 years, double-contrast barium enema every 5 to 10 years or colonoscopy every 10 years.

Screening Screening RecommendationsRecommendations

• CTFPHC-Insufficient evidence to recommend using FOBT screening in the periodic health examination of individuals older than age 40; insufficient evidence to recommend sigmoidoscopy in the periodic health examination; insufficient evidence to recommend screening with colonoscopy in the general population

• USPSTF-After age 50, yearly FOBT and/or sigmoidoscopy (unspecified frequency for sigmoidoscopy)

The EvidenceThe Evidence

• Screening for colorectal cancer reduces cancer-related mortality at costs comparable to other cancer screening programs. Given an expected screening compliance rate of 60% and current costs of the various procedures, annual rehydrated fecal occult blood testing plus sigmoidoscopy every 5 years is most cost-effective. If the cost of colonoscopy is reduced by 25% or more, screening every 10 years with colonoscopy is preferred by this model (LOE: 2b).

Frazier AL, Colditz GA, Fuchs CS, Kuntz KM. Cost-effectiveness of screening for colorectal cancer in the general population. JAMA 2000;284:1954-61.

More EvidenceMore Evidence

• 16% of colorectal cancers prevented with FOBT.• 34% of colorectal cancers prevented with flex sig.• 75% prevented with colonoscopy.• Colonoscopy q 10 years was more cost-effective

than flex sigs q 5-10 (LOE:?).

Sonnenberg A, et al. Cost-effectiveness of colonoscopy in screening for colorectal cancer. Ann Intern Med October 17, 2000;133:573-84.

Even More EvidenceEven More Evidence

• Screening with sigmoidoscopy: There is evidence from case control studies, to recommend that flexible sigmoidoscopy be included in the periodic health examination of patients over age 50 [B, II-2, III]. There is insufficient evidence to make recommendations about whether only 1 or both of fecal occult blood testing and sigmoidoscopy should be performed [C, I].

CMAJ 2001 Jul 24;165(2):206-8 [20 references]

IndicationsIndications

• Mostly for screening.

• Should consider colonoscopy if: previous polyps, family history of colon cancer, rectal bleeding, hemoccult positive stools, change in bowel habits, protracted diarrhea, surveillance in UC/Crohn’s, anemia, unexplained wt. Loss/fevers, abdominal pain.

ContraindicationsContraindications

• ABSOLUTE– Acute, severe cariopulmonary disease.– Inadequate bowel prep.– Active diverticulitis– Acute abdomen.– History of SBE or prosthetic valves with no

prophylaxis.– Marked bleeding dyscrasia.

ContraindicationsContraindications

• RELATIVE– Recent abdominal surgery (bowel or

pelvic).– Active infection– Pregnancy.

EquipmentEquipment

Additional EquipmentAdditional Equipment

• Light source

• Suction apparatus

• Biopsy forceps

• K-Y Jelly

• 4X4 inch gauze pads

• Nonsterile gloves

• Water container (for suction)

More equipmentMore equipment

• Video unit and monitor

• Anoscope

• Basin of water

• Formalin jars

• Disinfecting cleaner

ComplicationsComplications

• Bowel perforation (1/10000)

• Bleeding (increased risk with biopsy)

• Abdominal distention and pain

• Infection (SBE, infection from another pt.)

• Vasovagal symptoms

• Missed disease

Increased ComplicationsIncreased Complications

• Watch out for patients with previous bowel or pelvic surgery, irradiation, or diverticulosis.

• Caution with blind advancement (only limited distances).

Patient PreparationPatient Preparation

• Signed informed consent

• 2 fleets enemas (one 90 minutes prior, and one 30 minutes) before procedure

• Clear liquids after evening meal

• Take laxative if chronic constipation

• Take normal medications (caution with diabetics)

Clear Liquid DietClear Liquid Diet

• Beverages: carbonated, coffee, kool-aid (avoid red), tea.

• Desserts: Jello, clear popsicles

• Fruit: Apple juice, cranberry juice, grape juice

• Soups: Beef bouillon, clear broth

• Sweets: hard candy, sugar.

Anatomy ReviewAnatomy Review

The ProcedureThe Procedure

• Pt. Placed in left lateral decubitus position• Rectal examination first• Lubrication is key, don’t smear the lens• Either directly insert scope, or flex index

finger behind the scope.• Hold scope in left hand, use thumb for up and

down, use right hand for right-left (or can also use thumb).

RectumRectum

• Insert scope 7-15cm, insufflate and/or withdraw to visualize lumen

• Normal rectal mucosa is a nonfriable, vascular network.

• Proctitis produces an erythematous, friable mucosa, often with bleeding.

• Semilunar valves of Houston appear as sharp edges protruding into the lumen (there are 3) with shadows noted behind them.

RectumRectum

• Ulcerative colitis will produce erythema, friability, and mucosal bleeding.

Rectal Colon CARectal Colon CA

SigmoidSigmoid

• Redundant folds, hard to visualize lumen

• May have to: insufflate, extensive turning, torquing, accordionization, or dithering

• Avoid bowing out.

TechniquesTechniques

FIGURE 1.Hooking and straightening technique used to pass through a tortuous sigmoid colon. (A) The scope is inserted to the angled sigmoid. (B) The scope tip is turned to a sharp angle, and the sigmoid is hooked as the scope is withdrawn. (C) The sigmoid is straightened as the scope is withdrawn. The scope can then be inserted through to the descending colon.

Other TechniquesOther Techniques

FIGURE 2.Paradoxic insertion. (A) The scope is bowing out the sigmoid colon, which has a mobile mesenteric attachment. (B) Paradoxic insertion describes the insertion of the tube without advancement of the scope tip. Paradoxic insertion can be very uncomfortable for the patient.

Descending ColonDescending Colon

• Long, straight tube with concentric haustrae.

• Vascularity is random, reticular.• Polyps can either be mound-like

(sessile) or on a long stalk (pedunculated).

• Don’t mistake suction polyps or mucous for polyps!!

Pedunculated PolypPedunculated Polyp

DiverticulosisDiverticulosis

Crohn’s ColitisCrohn’s Colitis

C. Difficile ColitisC. Difficile Colitis

The Final Step-The Final Step-RetroflexionRetroflexion

• Accomplished by turning inner knob all the way “up” and outer knob all the way “right” while gently inserting and rotating 180 degrees.

• Make sure you are in rectum, and not to far from internal sphincter.

Retroflexion with Retroflexion with Hemorrhoid and Small Hemorrhoid and Small

PolypPolyp

Be nice to your patientBe nice to your patient

• Suction air out before terminating procedure!