HPT Correlation Criteria on the Medtronic HMS Plus

Hello, 
I'm not sure if you are specifically talking about Alternate Proficiency Testing for HPT cartridges?  I perform using the HepLine Linearity Kit for the Alternate PT Testing.  I only use Red, Tan, Blue and Green cartridges.  If you use other HPT cartridges, reach out to your HMS Sales Rep - possibly he can put you in contact with a HMS Specialist for the cut-off channels for other cartridges.  I have 4 HMS instruments - I perform the Alternate Assessment on one instrument, on a rotating basis (i.e, instrument A, Jan. 2023; instrument B, June, 2023, etc.).  Here is what I have in my policy.  Hope this helps.  

To perform the HEPline HPT Cartridge Alternate Proficiency test: 

1.      Remove each vial from the HEPline kit, tapping each one firmly to return any reagent to the bottom of the vial;   

2.      Uncap each vial, being careful to keep the cap from each vial in close proximity from the vial from which is was removed (NOTE:  recapping a vial with a lid from a wrong vial will result in erroneous results); 

3.      Place each uncapped vial from the HEPline kit in a plastic or wire rack; 

4.      Perform a venipuncture (A normal healthy donor, of any age, who is unheparanized, free of anticoagulant medications and has not taken aspirin within the last forty-eight (48) hours is suitable.  Thirty milliliter (mL) of fresh blood is collected via venipuncture using a 23 gauge butterfly.  The venipuncture must be clean with the first three (3) milliliters of blood discarded to avoid contamination of the sample with tissue thromboplastin; 

5.      Transfer blood into each heparinized vial up to the 5 mL mark; 

6.      Cap each vial tightly as soon as it is filled and gently invert the tube four to five times to mix the heparin with the blood.  If tubes will not be tested immediately,  invert the tubes again just before testing to ensure that a uniform sample is tested;   

a.      NOTE:  heparinized samples are stable at Room Temperature for ninety (90) minutes  

7.      Test the heparinized sample, using the appropriate HPT cartridge.  

Acceptance of results, HPT Cartridge Alternate Proficiency test:  

1.      For passage, each HEPline Kit vial sample must clot in the following cartridge channel: 

a.      Vial 1 (red) –     channel 3 or 4 

b.      Vial 2 (tan) –     channel 1 or 2  

c.       Vial 3 (tan) –     channel 3 or 4 

d.      Vial 4 (blue) –    channel 1 or 2 

e.      Vial 5 (green) – channel 1 or 2 

This is a CAP criteria for nonwaived testing. Check the updated Standards for this year for POCT general 

@david thrash 
I am talking about the 6 month correlations, not alternative proficiency testing but THANK YOU! 

The 6-months correlations for non-waived (high complexity) POCT tests, are part of the CAP POCT General standards. You are comparing every 6 month to the gold standard (laboratory instrument to the POCT instrument) 

@Cindy Sorensen- That is what we are currently doing is using QC to document the correlation but our form had this specific criteria listed which I found out is from Medtronic. We have a call scheduled later with our Medtronic Specialist to review this criteria and get more information. Can you explain your process a little more for what specifically you are reviewing on the tapes/patient runs (amount of heparin given to the HPT result it is expected to be at?) and how many you review? What do you consider matching? What do you do if it is not producing the expected results?

We currently use the QC material and compare it to the "expected results" for each cartridge we use. For Example:

We have not had any fallouts but the verbiage on our form that I listed in the OP was kind of confusing and we wanted to reword it so it was easier to understand. Like I said, we have a call with the rep to get a better understanding of this criteria definition so hopefully that will clear this up better for us. Thank you!




@Diana Sery- we do not perform this testing in the laboratory so there is no gold standard analyzer to correlate it to. We can only correlate our 6 devices to each other to adhere to the CAP standard. The standard I am looking at is actually part of the All Common Checklist, COM.04250 Comparability of Instruments and Methods - Nonwaived Testing and COM.04300 Comparability Criteria - Nonwaived Testing, are these what you are referring to when you say "POCT General standards"? We would still need to compare the 6 devices to each other (correct?) because we have multiple devices that report the same thing. ("This requirement only applies when the instruments/reagents are producing the same reportable
result") 
Thank you!

Kelly,
Can you call me when you get time?  I'll try to help :)
I'm in the office until 3pm CST

Cindy
314-205-6100 x5656

Yes Kelly, you are absolutely correct. And because there is no laboratory instrument that produces the POCT value result, the 6-instrument comparison to each other every 6 months is acceptable as based on the noted standards from CAP. I hope this helps. If you want more input, please do not hesitate to reach out.