i-stat iccnet CHSA Edition 1.2 Page 1 of 7 i-stat Rosy Tirimacco / Paul Simpson

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1 Page 1 of 7 i-stat Edition No: 1.2 Author: Rosy Tirimacco / Paul Simpson Date: January, 2012 Operative Date: January, 2012 Review Date: January, 2013 Location: Country Health SA Integrated Cardiovascular Clinical Network (iccnet CHSA)

2 Page 2 of 7 1. Principle Standard Operating Procedure i-stat Analyser The i-stat analyser utilises i-stat cartridges for the in vitro quantification of various analytes in the blood including: blood gases, ph, electrolytes, glucose, urea, creatinine, hematocrit and lactate. Analysis requires 2-3 drops of whole blood that the analyser tests and displays quantitative results in approximately 2 minutes. The single use cartridge contains calibrating solution, a sample handling system and all the sensors for the completion of the tests. The analyser automatically controls all steps in the testing cycle including fluid movement within the cartridge, calibration, continuous quality monitoring and thermal control for tests requiring it. Quality control is performed on the analyser by an electronic simulator, which checks the non-disposable components of the i-stat system. Testing of the analyser with liquid internal and external quality control samples provides a final full check of the total analyser system. 2. Specimen Collection For testing with i-stat cartridges FRESH whole blood from arterial, venous or skin punctures is required. Sample volume: 40µl, 65 µl or 95 µl depending on cartridge type. Test Timing: Within 3 minutes after collection when using capillary tubes, evacuated tubes or syringes without anticoagulant and when using cartridges that measure lactate. Within 10 minutes after collection when using evacuated tubes with Note: Anaerobic conditions must be maintained when analysing blood gases (ph, PCO2 and PO2) Use only fresh whole blood samples from skin (capillary), venous or arterial sites, either without anticoagulant or with balanced lithium or sodium heparin anticoagulant for later testing. Blood samples used to fill a cartridge must be collected and handled properly to ensure accurate results. Test sample immediately after draw. Samples drawn without anticoagulant must be tested within 3 minutes and those with anticoagulant within 10 minutes. If testing is delayed, remix by rolling between fingers and discard the first drop of blood. Sample Requirements Cartridge Syringes Evacuated Tubes Capillary Tubes

3 Page 3 of 7 Chem 8+ Without With lithium, sodium, or balanced heparin CG4+ Without With lithium, sodium, or balanced heparin Without With lithium or sodium heparin Without With lithium or sodium heparin Without With balanced heparin With sodium or lithium heparin if labelled for the measurement of electrolytes Without With balanced heparin With sodium or lithium heparin if labeled for the measurement of electrolytes 3. Cartridge Storage/Handling Select the appropriate cartridge for the tests or test required. For error free usage the cartridges should be handled as follows. A cartridge should not be removed from its pouch until it is at room temperature. Condensation on a cold cartridge may prevent proper contact with the analyser. Allow a single cartridge to stand for 5 minutes at room temperature before use. Use a cartridge immediately after removing it from its protective pouch. Do not contaminate the contact pads with fingerprints or talc from gloves, as the analyser may not be able to make proper contact with the cartridge. Do not apply pressure to the central area of the label as the calibrant pack inside could burst prematurely. Do not block the air vent as the sample will not flow to the fill mark and the calibrant solution will not flow to the sensors. To avoid contaminating the analyser, do not use a cartridge on which blood or any other fluid has spilled. Avoid filling cartridges on surfaces that may cause the cartridge to pick up fibers, fluid or debris that may lodge in the analyser.

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5 Page 5 of 7 4. Quality Control Electronic Control Perform electronic simulator check on each analyser once per day. The Electronic Simulator is inserted into the cartridge port of the analyser to verify electrical measurement. A PASS/FAIL message indicates whether the analyser s measurements are within specification. If a fail message appears in the display window on the analyser, repeat the test. If the instrument still fails, document the problem on the problem action log and contact iccnet technical support (page ). Liquid Controls Internal: Aqueous controls are used to verify the integrity of cartridges. Each level of control is packaged with a sheet with target values and acceptable ranges. The control solutions do not contain human serum or serum products. Store controls at 2 to 8 C. Control solution may also be stored at room temperature for up to 5 days. When using cartridges that contain sensors for ph, pco 2, PO 2 and ionised calcium a separate ampoule must be used for each cartridge being tested. Do not use the solution left in a syringe, ampoule or capillary tube for additional testing of cartridges that contain sensors for ph, pco 2, PO 2 or ionised calcium. Cartridges without these sensors may be tested with remaining fluids if within 10 minutes of opening the ampoule. Target values are printed on the value assignment sheet included with each box of control ampoules. Always be sure that the lot number printed on the insert matches the lot number on the ampoule in use. Level 1, Level 2 and Level 3 i-stat control levels. Run one control each month alternating between levels for each cartridge type and record results in the QC log. Results should be faxed to iccnet CHSA on External: External quality controls are sent to each site at the beginning of the year and contain 24 samples for testing. Due dates and result sheets are given for each of the samples (approx. 2 samples per month) and should be faxed to iccnetsa on upon completion. Procedure for internal and external quality control testing: 1. Remove sample from the refrigerator at least one hour prior to sampling and leave to equilibrate at room temperature. 2. Prepare i-stat instrument and cartridge for use. If using a blood gas cartridge (CG4+), always test this first as exposure to air will affect the results. All cartridges must be out of the refrigerator for at least 5 minutes before use.

6 Page 6 of 7 3. Use a 1 or 2ml tuberculin syringe to collect sample. DO NOT USE A NEEDLE to draw up the sample from the ampoule. 4. Shake the ampoule vigorously for seconds, holding only the top and bottom of the ampoule. 5. Swirl the ampoule gently to ensure the liquid returns to the bottom of the ampoule. Bubbles should remain on the liquid as a protective interface from air contamination. 6. Protect fingers with tissues and carefully snap off the neck of the ampoule and insert the end of the 1ml syringe into the opening of the ampoule. 7. Holding the syringe tightly in the opening of the ampoule, quickly invert the ampoule and syringe and draw at least 0.5ml into the syringe. 8. Load the sample into the test cartridge as you would when performing a patient test and insert into the analyser. 9. Once analysis is complete fill out appropriate sheet and fax results to the iccnet CHSA office on (08) Test procedure 1. Take the i-stat cartridge to be used out of the fridge and allow five minutes for it to come to room temperature. Ensure that at all times the test cartridge is handled on the side (as shown below) as touching the top may cause a test failure. 2. Collect patient s blood into a syringe and take to the i-stat analyser. Remove and place needle in a sharps container. Test should be performed within 3 minutes of collecting blood sample. NOTE: If performing the test on the CHEM8+ cartridge, blood may be taken into a lithium heparin vacuette, which allows the operator 10 minutes to perform the test. 3. Ensure no air bubbles are in the syringe by emptying a few drops on to a tissue. 4. Remove the cartridge from the individual pouch (do not discard pouch as this is needed to scan in the cartridge lot number). Place the syringe on a 45 angle to the cartridge sample well (as shown below) and gently fill the cartridge to the blue arrow.

7 Page 7 of 7 NOTE: Insert the blood into the cartridge very slowly as over-filling will cause a test failure. 5. Fold the closure tab until you here it snap into place. 6. Turn on the i-stat and select 2 (i-stat Cartridge). 7. Enter the operator ID and press enter. 8. Enter the patient ID (UR number) and press enter. Re-enter patient ID and press enter to confirm. 9. If a barcode is present on the cartridge pouch (i.e. CHEM 8+ cartridges), the lot number MUST be scanned in at this point by holding down the scan button and scanning the barcode. If no barcode is present on the cartridge pouch (i.e. CG4+ cartridges), press enter without entering the lot number. Insert the cartridge into the analyser when prompted. NOTE: Never remove a cartridge from the i-stat if Cartridge Locked is seen on the display. 10. The test will take two minutes to perform and results will be shown on the display. Press page to scroll to next page of results. 11. Remove cartridge and place in appropriate waste container. 6. Printing Results 1. Take i-stat analyser to the printer and align the infra red beams. 2. Press print on the i-stat and it should print automatically. As the paper from the printer will fade over time, ensure the printout is photocopied (along with patient details) and placed into the patient s notes.