rravkin@aol.com

Assuming that you are using the same ABS technique for both tube types I don't see why a series of serial dilutions (titers) of one or more anti-seras would not surfice your need. These titers should also work out your hypothetical reaction varience between the two tube types. As far as the level of fill of the pink tube I would further question the manufacturer for specifics.

When the initial ABS is positive and your panel, using the same technique, is negative, I think that using the alternative techniques such as PEG and Pre-Warm are worth while; but our ultimate goal is providing compatible blood products. I would not disregard any results if they are inconclusive and proceed with extended crossmatch for compatible units using the same technique for which the initial positive react was obtained. If compatible donor cells are acquired then we have acheived our goal. When futher testing is performed on new patient specimens after three or more days we wil then see if the positive result initially aquired will persist. If compatable units are not obtained then we should send out specimens to a reference lab for a complete workup. As far as weather to change an initial positive ABS result I would not only because you would want to maintain the record for future issues if any. If this initial positive was indeed a technical error it will work it's way out over time. As far as the response of Croydon I would be agreeable if the post testing were performed by different staff. Therefore, if the result was do to technical error you would have a better ability to find out the exact problem if any.

Hey Anyone, I am noticing that the posting I am veiwing are from 2006. Are there any current postings????

Labman, Also, the 30 to 45 degree angle of holding the pipette is a convention of practice formed to enable all practioners; laboratory techs; to dispence the same drop. As you know the angle that the pippette is held can alter the size of the drop such that if you have fourty employees practicing the same proceedure but all of which hold the pipette at different angles the procedure will potentially give different results per employee.

Labman, I think that what you are eluding to in your statement about the air bubble would apply if the cells were dispenced into the gel and let standing at room temp for a significant length of time before the plasma was added. The plasma should be added immediately after the cells and the card placed into the incbator right away. Therefore the cells do not have the opportunity to disipate into the gel prior to mixing with, and potentially reacting with, the free IgG in the plasma, if any.

Air bullbles in reaction volumes, such as that of the gel card, are not a good practice because they can cause an unequal distribution of the reactants and heat throughout the volume, such that, the reactions, if any, can be significantly altered and/or missed (ie false negative).