Acceptable Performance Ranges for Helmer Ultra CW cellwasher

[lehooke]

We are in the process of setting up our new Helmer Ultra CW cellwasher and I have a question about performing the tachometer checks. I am new to this facilty and they have been checking the rpms for the Pack rpm, the Decant rpm and the AHG rpms. I have never heard of checking all three of those readings for a cellwasher before. I have always only checked the rpms of the unit when it is spinning (packing?) Does anyone know if it's a requirement to perform tachometer checks for all three of these functions or is it sufficient to perform the one tach reading?

Thanks,

Lisa:confused:

[AMcCord]

We checked the RPMs for pack and decant with our old Sorval (may it rest in peace and boy, oh, boy do I miss having a cell washer!). We did not check for AHG RPMs because we didn't use it for that. If you do use it for AHG testing, you should definitely check it...it should be calibrated just like any serologic centrifuge for that use.

[Mabel Adams]

Does it run at a different speed for AHG than it does for packing? If not, I wouldn't see why you would need to check the rpms at both, unless you are checking the software's ability to run its program properly rather than whether the centrifuge is wearing out.

[AMcCord]

As I recall from a cell washer pre-Sorval days, though my memory may be out to lunch, the RPMs for AHG were different. Since the AHG spin would be a critical part of the crossmatch (or whatever test) process, wouldn't you want to ensure that the software was functioning correctly if the AHG was an automatic add? If not automatic, and the RPMs are different, I think you would still want to check it, as we do our serologic centrifuges at Lo and Hi speeds for test spins and wash.

Maybe checking Lo and Hi is over the top??? but I've never gotten a comment from an inspector about it, so we just keep on doing it and doing it and doing it........

[L106]

We have always just checked the rpm while the cell washer is centirfuging (ie: "packing.")

We "calibrate" the cell washer (ie: check it at 10 seconds, 15 seconds, 20 seconds, 25 seconds, etc.) to determine the optimum length of time to spin for the AHG (Coombs) phase.

[tbostock]

Same as L106 here.

[Mabel Adams]

The method of Terri and L106 will catch any problems with the cell washer running the AHG phase correctly and you won't have to check tachometer on that specifically. Since you have to do it anyway, that seems like a good approach. The chance that it will still work for everything but AHG when that fails seems so rare that the annual calibration should catch it. Or your daily use will catch it.