Policy/Principle: | Clinical Significance: | Certification: | Specimen: | Materials: | Reagents: | Standardization: | Procedure: | Limitations: | Results Derivation: | Expected Results | Quality Control | Cleaning Monitor: | Replacing Batteries: | Reviewing Results | References:
The Alere INRatio2 INR test is CMS “Waived” status, obviating Equivalent QC and Calibration Verification as stated in CLIA regulations. This test is performed as a definitive function to monitor warfarinized patients’ INR. Results of the test could trigger therapeutic interaction without reflex laboratory analysis.
The Alere INRatio2 INR test strip contains human recombinant thromboplastin, stabilizers, preservatives and additives. When whole blood is applied to the test strip, the Alere INRatio2 meter provides an electrochemical measurement of prothrombin time following activation of blood coagulation with human recombinant thromboplastin.
When the blood clots, changes in impedance in the sample are detected by the monitor. The monitor calculates the PT and INR results from this impedance change using calibration information entered as a Test Strip Code, and displays results on the monitor.
Specimen integrity will be critical. Therefore, formal certification in capillary puncture is required.
The INR (International Normalized Ratio) is the ratio of the patients’ Protime to the method-specific population Protime mean offset (via ISI; i.e., International Sensitivity Index) to match, theoretically, the thromboplastin activity of the WHO’S IRP (World Health Organization’s International Reference Preparation). It is a Protime reporting format which should provide a standardized scale for monitoring warfarinized patients and allow effective transferability of Protime results between disparate laboratories and methods.
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. INR testing will be performed by specifically certified staff.
A. Certification requires completion of the Alere INRatio2 INR Testing in-service.
B. Operators must be certified in capillary puncture.
C. If the individual seeking certification is unable to demonstrate acceptable capillary puncture technique he/she must be retrained and successfully retested for authorization to perform INR testing.
D. If the individual seeking certification is unable to demonstrate acceptable performance, he/she must be retrained and successfully re-tested for authorization to perform INR testing.
E. Re-certification is required annually:
a. Re-certification for an individual may be required more often if deemed necessary. When an instructor observes improper technique, he/she may decertify the operator immediately. Arrangements for re-certification of that individual must be made through their immediate supervisor.
b. Re-certification requires an operator to successfully complete the Alere INRatio2 INR Testing Self-Instructional Competency documentation packet.
F. Certification Records:
The certification record of operators and instructors will be maintained at Finley Home Care.
1. Specimen Requirements: Capillary whole blood is the only acceptable sample type. Capillary whole blood will be used by applying sample directly to the test strip.
Notes: It is absolutely essential that the capillary puncture for coagulation 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.
2. Specimen Collection:
A. Assemble the necessary equipment:
a. Lancet device
b. Cotton ball or gauze pad
c. Alcohol wipe
d. Fresh, non-sterile gloves; changed for each patient encounter.
B. Capillary Puncture using a lancet device:
a. When possible, patients will 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. Position the lancet on the puncture site. For a “normal” puncture depth, place the oval opening “across” the long axis of the digit. For a “deeper” puncture, position the oval opening “with” the long axis of the digit.
e. While applying a small amount of pressure on the lancet device against the puncture site, press the trigger.
f. Gently milk the area to produce a large hanging drop of blood. Do not “squeeze” the tissue around the puncture site.
g. The first drop of blood is used for testing on the Alere INRatio2 INR test. DO NOT wipe the first drop of blood.
h. When testing is complete, discard the lancet device. Lancets are not to be reused, even on the same patient.
i. Rotate puncture sites on each patient to minimize soreness.
1. Alere INRatio2 Monitor
2. Laboratory-approved Lancet device
Alere INRatio2 INR Test Strip
Store strips at room temperature (2 - 32°C). Strips are stable until expiration date on the label.
1. Store strips in the original foil pouch until ready to use.
2. Use the test strip within 10 minutes of opening the foil pouch.
3. Do not leave the test strips in conditions above 90°F/32°C, such as in your car in the summer or on a window ledge in the sun.
4. Do not freeze the test strips.
Each lot of test strips is calibrated to a reference lot that is traceable to the WHO International Reference Preparations using a code specific for the lot number.
1. Ensure that Test Strip and monitor are at room temperature.
Note: The Low temperature or High temperature symbol; will appear on the display if the ambient temperature is outside the operating range of the monitor. You will not be able to perform a test until the ambient temperature is within the monitor’s operating range.
2. Place the monitor on a level surface that is free of vibrations. Do not hold the monitor in your hand while running a test. Testing on an uneven surface or shaking may cause inaccurate results.
3. Turn ON the monitor by pressing the OK button. The monitor will automatically perform a self test where all symbols will appear on the display.
4. Remove a fresh test strip from its foil pouch. Insert it into the test strip guide so that the clear end with the vertical contact bars goes in first. Make sure the sample well in the strip lines up with the green light on the test strip guide. (If the test strip is inserted incorrectly, the monitor will not recognize that the strip has been inserted, and will not perform the test.)
5. Match the code on the monitor display with the strip code on the test strip pouch.
A. If the codes match, press OK.
B. If the codes do not match, use the Up and Down buttons to change the first digit of the code which will be flashing. Press the OK button to accept the first digit and move to the next digit. Change each digit using the Up and Down buttons, then press the OK button to accept each digit and move to the next digit.
6. The monitor will count down and display the Temperature symbol as it warms up for the test.
7. The monitor display will prompt you to apply a blood sample when it’s ready to perform a test. The monitor will beep and a green sample target light will also appear through the test strip sample well.
8. Perform a finger stick when the monitor prompts you to apply a drop of blood.
9. Immediately apply a large hanging drop of blood to the Test Strip, directly over the green light. Hold the finger in place until a beep sounds indicating that sufficient sample was added.
10. Do not move the monitor or the finger as you apply the sample.
A. If the monitor does not beep and begin processing, an error message will state that not enough blood was applied. In this case, do NOT attempt to apply more sample. Retest with a new test strip and perform a new fingerstick.
B. If the blood sample was applied before the monitor was ready, the CAUTION symbol will flash on the display. In this case, remove the test strip. Do NOT add more blood to the test strip. Retest with a new test strip and perform a new fingerstick.
11. Results will be displayed in less than 2 minutes
12. When testing is complete, the monitor will beep and the results will appear on the display along with the date and time. The QC results for the high and low controls will also appear.
13. Record the patient INR and the QC results on the INRatio2 log.
14. Turn the meter OFF by pressing and holding the OK button.
15. Discard all materials that have come in contact with blood in a biohazard container.
1. The Alere INRatio2 INR Test should not be used for screening purposes.
2. The presence of anti-phospholipid antibodies (APAs) such as Lupus antibodies (LA) can potentially lead to prolonged clotting times, i.e., elevated INR values. A comparison to an APA-insensitive laboratory method is recommended if the presence of APAs is known or suspected.
3. A hematocrit higher that 55% or lower tha30% can cause inaccurate results.
4. In vitro studies show the INRatio system to be sensitive to levels of heparin and low molecular weight heparin of 4 U/ml or greater. This test should not be used for patients on heparin therapy.
5. Certain prescription drugs and over the counter medications (e.g. antibiotics, pain relievers) can affect the action of oral anticoagulants. Starting, stopping or changing the dose can affect the INR value.
6. Liver disease, congestive heart failure, thyroid dysfunction and other diseases or conditions can affect the action of oral anticoagulants and the INR value.
7. Changes in diet, lifestyle or taking nutritional supplements such as ginkgo biloba can affect the action of oral anticoagulants and the INR value.
1. INR results will be displayed on the monitor screen. INR is calculated by the analyzer using a fixed normal population mean of 12.0 and reagent ISI of 1.0.
2. Results are documented on the patient’s chart.
3. The INR analytical range is 0.8 to 8.0. If the INR result is < 0.8 or > 8.0 the result must be confirmed by the laboratory analysis. Report the result with the comment “PT/INR should be re-ordered for Laboratory confirmation.”
4. If there is a questionable result, i.e. too high, critical or too low notify the patient’s physician immediately. Document on the patient log that the result was called to the physician along with initials of the person to whom the result was reported.
1. Target INR Ranges (set by physician)
A. 2.0 - 3.0
B. Mechanical Valve: 2.5 - 3.5
≥ 5.0 for orally anticoagulated patients
1. Each time an INR test is performed, a Low and High control test are performed automatically by the monitor. If either or both controls are out of range, the monitor will display a flashing CAUTION symbol, and a “LO QC1” or “LO QC2”, “HI QC1” or “HI QC2” message.
2. A “LO” or “HI” QC message appears when the test strips have expired, or have not been stored properly and have deteriorated. If a “LO” or “HI” QC message is displayed, check to make sure the test strips have not expired, that the correct strip code was entered in the monitor and confirm that the strips have been stored properly.
-If the strips are outdated, obtain new strips.
-If the strip code is incorrect, enter the correct code.
-If strip deterioration is suspected, notify the UCL Office of the Technical Director.
1. Turn the instrument OFF.
2. Using an isopropyl alcohol pad, gently wipe off the exterior of the instrument. DO NOT use sprays of any sort.
3. Clean the area around the test strip guide with a swab or pad that has been dampened with isopropyl alcohol.
1. The monitor batteries should be replaced whenever the Low Battery symbol appears with the flashing CAUTION symbol after turning the monitor ON. The batteries still have enough power to perform a test but should be replaced as soon as possible.
2. Turn the monitor upside down so that the bottom is facing you.
3. Remove the battery door by pressing down on the battery door release.
4. Remove the old batteries and replace with 4 standard AA batteries
5. Replace the battery door.
The latest 60 results are available for on-screen review.
1. Press the Memory button “M”. The most recent result will be displayed.
2. Use the down button to scroll to the previous results.
3. To exit Memory Mode, press the OK button.
1. Alere INRatio2 PT/INR Professional Testing System User Guide. Alere San Diego, Inc. San Diego, CA. Rev. A 201/07/22
i. April 2011 L. McGovern
Representative: Finley Home Care