Policy: | Certification: | Testing Prerequisites: | Specimen: | Materials: | Procedure: | Limitations: | Results Derivation: | Expected Result(s) | Quality Control: | Infection Control: | References:
This test is performed as a definitive function to monitor patient’s Hemoglobin A1c. Results of the test could trigger therapeutic interaction without reflex laboratory analysis.
Only certified operators may perform the Hemoglobin A1c test. Established Quality Control and Infection Control Policies are followed.
A diluted whole blood mixture is directly applied to the sample port, and results are displayed in numeric form on the monitor’s liquid crystal display after 5 minutes. The monitor self-activates upon insertion of the Test Cartridge.
The A1c Now+ monitor utilizes both immunoassay and chemistry technology to measure HbA1c and total hemoglobin. Upon the addition of the diluted blood sample, blue microparticles conjugated to anti-HbA1c antibodies (sheep polyclonal) migrate along reagent strips. The amount of blue microparticles captured on the strips reflects the amount of HbA1c in the sample.
For the total hemoglobin (Hb) portion of the test, the sample diluent converts Hb to met-Hb, which is red-brown in color. The intensity of red-brown color measured on the reagent strips is proportional to the concentration of hemoglobin in the sample. Test results are express as %HbA1c (HbA1c/total Hgb x 100).
Calibration of the A1c Now+ is performed with a set of blood samples that have been value-assigned by a National Glycohemoglobin Standardization Program (NGSP) certified laboratory using an NGSP reference method. Total Hb calibration values for those samples are obtained with a Total Hb analyzer (HemoCue Hemoglobin Test System, HemoCue Inc., Lake Forest, CA). The calibration of the A1c Now+ test is thus traceable to the NGSP, and an NGSP Certified Network Method.
1. Orientation, authorization and competency of staff and licensed practitioners performing POCT are provided by the director’s (named on the CLIA certificate) designee as indicated in the “Point of Care (POCT) Program” procedure.
2. Only certified operators will perform Whole Blood Hemoglobin A1c testing.
A. To be certified, an operator must successfully complete the requirements of the Hemoglobin A1c, Whole Blood; POCT - Operator Certification Record. He/she must have read and understood the principles written into the Capillary Puncture Procedure (See IV. of this procedure) and the Hemoglobin A1c, Whole Blood; POCT procedure
B. If the individual seeking certification is unable to demonstrate acceptable capillary-puncture technique and/or is unable to demonstrate acceptable testing technique, he/she must be retrained and successfully retested for authorization to perform POCT for whole blood Hemoglobin A1c testing.
C. Recertification is required annually.
Complete the "Hemoglobin A1c, Whole Blood; POCT" self-instructional/competency documentation packet.
D. The certification record of operators and instructors will be maintained in the department.
The only designated Hemoglobin A1c test for the Hemoglobin A1c Testing; POCT Program is the Metrika A1c Now+.
5 µl capillary whole blood, or venous whole blood collected in a lithium heparin tube is acceptable specimens. Blood should be well-mixed, and tested at room temperature. Venous blood samples are stable for up to 8 hours at room temperature, and up to 14 days if refrigerated.
Note: It is absolutely essential that the capillary puncture for HbA1c testing produce a free-flowing, hanging drop of blood. Anything short of this will simply not generate reliable results! If the puncture does not produce a free-flowing, hanging drop of blood, THE TEST MUST NOT BE RUN.
Sample integrity problems can often be prevented if a warm washcloth is used to enhance capillary bed circulation in the patient’s hand for just a minute or two prior to the procedure.
A. Assemble the necessary equipment:
Note: The fingerstick device must be single-use and auto-disabling such as the MediChoice Pre-set safety lancet, 4863mc5020 through Owens and Minor.
The CDC has noted reports of increasing HBV infection outbreaks linked to diabetes care and warn that fingerstick devices should never be used for more than one person and that the single-use device should be auto-disabling.
a. single-use fingerstick device
b. Tenderfoot for heelsticks
c. MediChoice Pre-Set Safety Lancet Low Flow
d. Cotton ball or gauze pad
e. Alcohol wipe
f. Fresh, non-sterile, latex-free gloves; changed for each patient encounter.
B. Capillary Puncture on a Finger Using the site approved Blood Sampling device:
a. When possible, instruct patient to wash their hands in warm soapy water, rinse, and dry completely.
b. Place the patient’s hand in a dependent position. If the patient’s fingers are cold, wrap a warm washcloth around the fingers for several minutes prior to performing the puncture.
c. Cleanse the puncture site with an alcohol pad just prior to the procedure; allow the site to air dry. The area is then “milked” very gently to encourage capillary flow.
d. Positioning the lancet on the finger puncture site:
Position the oval opening across the long axis of the digit for a normal depth.
Position the oval opening with the long axis of the digit for a deeper puncture.
e. While applying a small amount of pressure on the blood sampling device against the puncture site, press the trigger.
f. Using a clean tissue, cotton ball or gauze; wipe away the first drop of blood.
Note: The first drop of blood is mostly tissue fluid and will not give an accurate result.
g. Gently milk the area to produce a large hanging drop of blood. Do not “squeeze” the tissue around the puncture site.
h. When testing is complete dispose of the lancet in a sharps container. Lancets are not to be reused, even on the same patient.
i. Rotate puncture sites on each patient to minimize soreness.
1. Metrika A1c Now+ Test Kit (Metrika #03015) Obtain from Finley Purchasing.
The kit contains 1 test monitor, 10 Test Cartridges and 10 Sample Dilution pouches.
A. The A1c Now+ monitor, Test Cartridges and Sample Dilution kits are stable until the expiration date when stored refrigerated at 2 - 8°C.
B. Monitor, Test Cartridges and Sample Dilution kits must be at room temperature for at least 1 hour before using.
C. Pouched A1c Now+ Monitors, Test Cartridges and Sample Dilution kits may be stored at room temperature for up to 3 months prior to use.
D. Leave all components in their sealed pouches until use.
E. Do not mix pouches and Monitors with Cartridge and Sample Dilution kits from different lots.
2. NOD™ A1c Control Levels 1 and 2 (Nova-One Diagnostics #HbA-G13133-050)
A. Store controls frozen at -20°C. Controls are stable until the expiration date printed on the container.
B. Frozen control should be thawed at 2-8°C and mixed by gentle inversion prior to use.
C. Controls are stable for 120 days after opening, stored refrigerated 2 - 8°C. Refrigerated control should be mixed by gentle inversion prior to use.
1. Allow the A1c Now+ monitoring kit and sample dilution supplies to come to room temperature for at least 1 hour before running the test. Make sure all components are the same lot number.
2. Once the A1c Now+ monitor, Test Cartridges and Sample Dilution kit have been at room temperature for at least 1 hour, remove them from the pouches and place them on a clean flat surface. Test immediately.
A. Have the patient wash hands in warm water, or clean finger with alcohol. Make sure the finger is completely dry.
B. Perform the fingerstick procedure to obtain a large drop of blood (5 µl).
4. Venous Sample: Obtain a blood sample by venipuncture in an EDTA tube. Mix the sample well before testing.
5. Hold the tip of the blood collector horizontally against the blood drop (fingerstick), or blood volume (EDTA tube) and allow the capillary to fill to the line with blood. The blood will stop when it reaches the line.
6. Check the capillary to be sure blood level is at the line. Wipe off excess blood using a gauze pad. Be careful not to wick any blood out of the collection device. If under-filled, fill to the line with blood.
7. Insert the blood collector into the sample body using a twisting motion.
8. Shake the sample body 6 to 8 times.
9. Stand the sample body on the counter, base end down. (From this point the test must be completed within 15 minutes.)
10. Open pouch #2 and insert the cartridge into the monitor immediately. The display will turn on and show “SMPL”.
Note: The code on the monitor must match the code on the cartridge. If the code numbers do not match, DO NOT continue with the test.
11. Place the monitor on a flat surface.
12. Remove the base from the sample body.
13. Place the base end of the sample body over the cartridge sample well and push down gently. Hold the sample body in place for 1 second.
14. The display will start counting down for 5 minutes, and then will show test results alternating with the letters “QC OK”. Do not handle the monitor until the result is displayed. The results will remain displayed for 30 minutes or until the next Test Cartridge is inserted.
15.. If any quality control checks do not pass, an error message (QC1 to QC99) will appear in the window instead of a number. If this occurs, repeat the test using a new A1c cartridge and a new sample dilution kit. If repeat test quality control fails, contact UCL Office of the Technical Director (563) 556-2010 ext.124 or ext. 156.
16. If any Out Of Range (OR) situations arise, a message (OR1 to OR6) will appear in the window.
A. If OR5 or OR6 are obtained this indicates a temperature problem. Ensure that a new A1c cartridge and sample dilution kit is at room temperature and repeat test.
B. If any other OR error is displayed, test must be performed by an alternate method.
17. When the test is finished, remove the cartridge and discard in a biohazard waste container.
18. The monitor is reusable until all the cartridges in the kit are used. The monitor will display 3TL, 2TL, 1TL and 0TL, alternating with “QC OK” and the result when there are 3, 2, 1 and 0 tests left. After all the cartridges in the kit are used, the monitor will expire.
1. If the patient has high levels of Hemoglobin F, Hemoglobin S, Hemoglobin C, or other hemoglobin variants, the A1c Now+ may report incorrect results.
2. Any cause of shortened red cell survival (e.g., hemolytic anemia or other hemolytic diseases, pregnancy, recent significant blood loss, etc.) will reduce exposure of red cells to glucose. This results in a decrease of %HbA1c values. Percent HbA1c results are not reliable in patients with chronic blood loss and consequent variable erythrocyte life span.
3. Rheumatoid Factor in high amounts will cause low results, or an error code. It is recommended that A1c be checked by an alternate method.
1. Results are displayed in the display window after 8 minutes and will remain for about one week Results are expressed as %HbA1c.
2. The A1c Now+ test is linear from 4%HbA1c to 13%HbA1c, and produces reliable results with a hematocrit between 20% and 60%.
A. If %HbA1c result is less than 4%, less than 4.0 will be displayed.
B. If %HbA1c result is greater than 13%, greater than 13.0 will be displayed.
1. %HbA1c reference range for nondiabetic patients: 4 - 6%
2. %HbA1c reference ranges for diabetic patients:
A. Controlled %HbA1c: less than 7%
B. Poorly controlled: greater than 8%
1. Before using the kits, check the temperature dot located on the box flap. If the dot has not changed color the product is okay to use. If the temperature dot has changed color the product should not be used.
2. Endogenous Controls: Each A1c Now+ monitor performs over 25 internal chemical and electronic quality control checks, including potential hardware and software errors (e.g., cartridge alignment, programming) and potential reagent strip errors (e.g., insufficient sample volume, invalid calculations). The monitor has been programmed to report an error code if these quality checks are not passed.
3. Exogenous Controls:
A. CMS “Waived Status”.
B. The Level 1 and Level 2 HbA1c Controls will be run for each lot number of each shipment received regardless of whether the lot number has changed. A Supervisor ensures that those individuals who are authorized to run POCT run the quality control on a rotational basis. Nursing staff record their results in a log, which documents their identity, the date and time and allowance tolerances. Logs are kept on site and are reviewed periodically by the Office of the Technical Director, for compliance and to ensure that the task is routinely rotated among the personnel who perform the test.
C. If a control fails to generate the expected reaction response, do not use the kit; complete the following procedure:
a. Repeat the Q.C. test.
b. Document the failed test result and repeat test on the designated laboratory test log. Notify the Site Supervisor and the office of the UCL Technical Director immediately.
c. Indicate in the designated Metrika A1c Now+ Test log who was called along with the date and time of the call.
1. Staff will wash their hands before and after the procedure using proper technique and will wear a fresh pair of latex or vinyl gloves while performing the capillary stick and the Hemoglobin A1c test.
2. Patients having a fingerstick are to wash their hands with soap and water, when possible. If handwashing is not possible, their hands or the puncture site is to be cleansed with a prepackaged towelette containing alcohol.
3. Dispose of all lancets in a sharps container. All other soiled materials used in the testing are disposed in accordance with the hospital approved waste management policy.
1. Metrika A1c Now package insert. Metrika Inc. Sunnyvale, CA. 90067 rev. B.
2. Metrika A1c Now Inview package insert. Metrika Inc. Sunnyvale, CA. PN 90553 rev. A.
3. Metrika A1c Now+ Professional Procedure Guide. Metrika Inc. Sunnyvale, CA. 90474. rev.A.
4. A1c Control Levels 1&2 package insert. Nova-One Diagnostics. Woodland Hills, CA.
5. Metrika A1c Now+ Professional; Use Product Insert. Metrika, Inc. Sunnyvale, CA. 90747, rev.A.
i. September 2002 L. McGovern
ii. March 2006 L. McGovern (Revised: for A1c Now Inview Test)
iii. September 2007 L. McGovern (Revised: for A1c Now+ Test)
iv. June 2009 L. McGovern (Revised: V.10.)
v. July 2009 L. McGovern (Revised: IV.2.; XII.4. added)
vi. October 2009 L. McGovern/S. Raymond (Revised: II.1. added)
vii. September 2010 L. McGovern (Revised: IV.2.)
Representative: Kehl Diabetes Center
Interim Review: September 2011 L. McGovern (Revised: V.1.E., 2., C.; VI.9.; XII.5.)