The occult blood Hemoccult test is a rapid, convenient, and qualitative method for detecting fecal

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1 TITLE/DESCRIPTION: Occult Blood in Fecal Specimens Waive Testing DEPARTMENT: Emergency Department PERSONNEL: All EFFECTIVE: 09/2012 REVISED: 3/14 PURPOSE The occult blood Hemoccult test is a rapid, convenient, and qualitative method for detecting fecal occult blood which may be indicative of gastrointestinal disease. It is NOT a test for colorectal cancer or any other specific diseases. It is used as a diagnostic aid during routine physical examination when hospital patients are first admitted to monitor for bleeding in patients recuperating from surgery, patients with gastrointestinal bleeding with iron deficiency anemia, peptic ulcer, ulcerative colitis, and other conditions, and in screening programs for colorectal cancer. PRINCIPLE The occult blood test consists of a special guaiac impregnated paper. A smear from a stool sample is applied to one side of the paper, the paper is turned over, and a special developer is added. The test reaction is based on the oxidation of guaiac by hydrogen peroxide to a blue colored compound. Hemoglobin, if present in the fecal specimen, acts as a pseudo-peroxidase material. It catalyzes the oxidation of alpha guaiaconic acid (active component of guaiac paper) by hydrogen peroxide (active component of the developer) to form a highly conjugated blue quinine compound. Appearance of any blue color on the specimen area of the slide is an indication of the presence of occult blood. POLICY Task Classification/ Precautions:

2 1. CLIA Classification: Waived 2. Precaution Category: Universal Precautions a. Justification: High risk for exposure to blood/body fluids b. Protective Wear: Gloves Operator Certification 1. Only a Certified Operator will be allowed to perform the point-of-care occult blood procedure. 2. A certified operator is an employee who has attended the initial training and successfully completed the competency performance for this procedure. 3. In order to maintain the status of Certified Operator, all operators are required to demonstrate continuing competency on an annual basis. 4. It is the Nurse Managers responsibility to ensure that all staff performing this procedure is currently certified. Competency Verification 1. An operator must attend initial training offered by the Nurse Manager or designee, and demonstrate competency through direct observation. 2. An operator must pass a written test offered by the Nurse Manager or designee. Annual Competency Verification: 1. Demonstrate competency to a certified nurse/ Charge Nurse/ Nurse Manager on Annual Competency Checklist, and 2. Complete a written test. Record of Certification 1. The Staff Development Department maintains education course records in the Staff Development Department. 2. Subsequent re-certifications will be noted on Annual Competency Checklists. 3. Individual educational files are also placed in the nurse's personnel file maintained by the Nurse

3 Manager. SPECIMEN PREPARATION AND COLLECTION Ideally, the patient should be placed on a high fiber, meat-free diet three days before testing and continuing throughout the test period. Such a diet minimizes false positive reaction and provides roughage to help uncover silent lesions that may only bleed intermittently. For most accurate results, collect specimen before contact with the toilet bowl water. Stool sample should be collected in a clean, dry container, labeled with patient identification from properly identified patient. Random stool samples from ED patient may also be tested, with consideration of the limitations. INTERFERING SUBSTANCES The following items and medications may cause false POSITIVE and should be discontinued prior to testing and during the testing procedure: 1. RED MEAT (Avoid for 3 days prior and during collection) 2. ASPIRIN (>325 mg/day) and other non-steroidal anti-inflammatory drugs such as ibuprofen and naproxen. Avoid 7 days prior and during collection. Acetaminophen is NOT expected to affect results. 3. ALCOHOL in excess The following can cause False NEGATIVE results: 1. ABSORBIC ACID 2. VITAMIN C enriched foods in excess 3. Iron supplements which contain quantities of Vitamin C in excess of 250mg/day. The interfering food items and medications should be stopped ONLY with consent of the provider.

4 It is recommended that specimen from two different parts of the stool be tested on each three consecutive days. Gloves, hands, and working areas must be free from blood. Patient with overt bleeding (e.g. hemorrhoids or menstrual bleeding) should not be tested. Diet may include the following: 1. Meats: Well-cooked pork, poultry, and fish. 2. Vegetable: Any cooked fruits and vegetables. 3. High fiber food: Whole wheat bread, bran cereal. Specimens may be rejected due to the following: 1. Specimen other than stool (I.e. gastric fluid, sputum, urine). 2. Thick-smeared test cards are unacceptable for testing. THIN smears only will be tested. 3. Unidentified/unlabeled test cards submitted by patient 4. Stool inoculated test cards older than 14 days REAGENTS 1. Hemoccult slide ( test cards) 2. Hemoccult Developer 3. Applicator Sticks PRECAUTIONS 1. For in vitro diagnostic use 2. Do not use after expiration date which appears on each test component. 3. Interpretation of test should not be done by one who is color blind.

5 4. Keep cover flap of slide (yellow and green striped card) sealed until ready to use. Protect slides from heat, light and volatile chemical. Hemoccult slides present no hazard to user. 5. Hemoccult Developer (yellow striped label with yellow bottle cap) should be protected from heat and the bottle kept tightly capped when not in use. It is flammable and subject to evaporation. Hemoccult Developer is an irritant. Avoid contact with skin. Do not use in eyes. Should contact occur, rinse promptly with water. STORAGE AND STABILITY Store product at controlled room temperature 15 to 30 C (50 to 86 F) in original packaging. Do not refrigerate or freeze. Protect from heat and light. Do not store with volatile chemicals (e.g., iodine, chlorine, bromine, or ammonia). Hemoccult Slides and Developer, stored as recommended, will remain stable until the expiration dates which appear on each slide and developer bottle. Do not use after expiration date. INTERNAL QUALITY CONTROL The function and stability of the slides and developer can be tested using the on-slide Performance Monitor feature. The positive (+) and negative (-) Performance Monitor Areas are located below the sample windows on the developing side of the slides. The positive Performance Monitor area contains a hemoglobin-derived catalyst which will turn blue within 10 seconds after applying developer. The Negative Monitor will not turn blue upon addition of the Developer. The Performance Monitor feature provides assurance that the guaiac paper and developer is functional. In the unlikely event that the Performance Monitor areas do not react as expected after applying developer, the test results should be regarded as invalid. If this occur, repeat test using another slide. QUALITY CONTROL, CORRECTIVE ACTION:

6 1. If Quality Control Monitors do not perform as expected do not report results. 2. Check expiration dates on Guaiac slides and developer. 3. Review procedure 4. Repeat control monitors with a new slide and freshly open developer. 5. If successful, discard old vial of developer. 6. Using a new slide repeat patient test and controls. 7. If the controls do not perform correctly on repeat, call the manufacturer of Hemoccult at SmithKline Diagnostics, and notify the POC Coordinator. PROCEDURE 1. Identify slide with appropriate patient information. 2. Using an applicator stick, collect a small fecal sample and apply a thin smear inside Box A. 3. Reuse the applicator to obtain a second sample from a different part of the feces and apply a thin smear to Box B. 4. Close cover flap. Dispose of applicator in waste container. 5. If testing immediately, wait 3 to 5 minutes before developing. Otherwise, slides may be stored up to 14 days until ready to develop. 6. Open back of slide and apply two drops of Hemoccult Developer to guaiac paper directly over each smear. 7. Read patient test results within 60 seconds. Any trace of blue on or at the edge of the smear is positive for occult blood. 8. Apply one drop only of Hemoccult Developer between the positive and negative Performance Monitor areas. 9. Read QC results within 10 seconds. If the slide and developer are functional, a blue color will appear

7 in the positive Performance Monitor area, and no blue will appear in the negative Performance Monitor area. Neither the intensity nor the shade of blue from the Positive Performance Monitor area should be used as a reference for the appearance of positive test results. Any blue originating from the positive Performance Monitor area should be ignored when reading the sample test results. INTERPRETATION Positive-any trace of blue indicates a positive test for occult blood Negative-no evidence of blue indicates a negative test for occult blood. NOTE: Occasionally, a light blue discoloration may be noticed on the guaiac test paper. This discoloration does not affect accuracy or the performance of the test when it is developed and interpreted according the recommended procedure. When developer is added directly over the fecal smear on a discolored slide, the blue background color migrates outward. A blue ring forms at the edge of the wetted area, leaving the guaiac paper around the fecal smear off-white color. Any blue on or at the edge of the smear is positive for occult blood. Proper storage of Hemoccult Slides will help prevent blue discoloration. Some specimens have a high bile content, which causes the feces to appear green. A distinct green color (no blue), appearing on or at the edge of the smear within 60 seconds after adding Hemoccult Developer, should be interpreted as negative for Occult blood. A blue or blue-green color should be interpreted as positive for occult blood. LIMITATIONS OF PROCEDURE Bowel lesions, including some polyps and colorectal cancer, may not bleed at all or may bleed

8 intermittently. Also, blood, if present, may not be distributed uniformly in the fecal specimen. Therefore, as with any occult blood test, results with the Hemoccult cannot be considered to provide conclusive evidence for the presence or absence of gastrointestinal bleeding or pathology and should be correlated with clinical finding. Hemoccult tests are designed for preliminary screening as an aid to diagnosis. They are not intended to replace other diagnostic procedures such as sigmoidoscopy, colonoscopy, barium enema, or other x-ray studies. No confirmatory testing using this method is required. Additional diagnostic testing is at the discretion of the provider. REPORTING RESULTS Hemoccult results are documented as Positive or Negative in HIS on the ED Assessment Flowsheet under Hemoccult Results section and are reported to the ED physician. Performed By is used to document who performed the test. If test was done by someone other than the person doing the charting, that person s name is entered. The acceptability of the Internal Positive and Negative Performance Monitor Area (internal controls) is also documented along with the patient results. REFERENCES Hemoccult Package Insert, Beckman Coulter, Inc, Brea, CA, EA, September 2009