Elution Competency

[bevydawn]

I had an issue at my facility recently with a tech trying to pull the "I don't know how to, it's been too long" pertaining to performing an elution, so she choose not to do it and to send it to a reference lab (it was an off-shift when I was not there). I came in the next day, completed the workup and called the reference lab to cancel what she had sent. Elutions are something that we do and is included as part of our training for new employees. Because we offer it, obviously we also do the CAP survey. My question is, can anyone offer suggestions for making a competency for all of my techs to do to keep them up on how to do an elution? I rotate my surveys but have around 20 techs that work in blood bank at least a couple of shifts a month and only 4 survery samples a year. Many of them are "lucky" and may not have a patient with a positive DAT that requires an elution for quite sometime so they get out of the groove. I usually use my old surveys for students and new employees. Can anyone tell me how to make a sample for an elution that will work? I will greatly appreciate it (though my techs may not!).

[David Saikin]

Pick an antibody (anti-D is the easiest). Sensitize some Rh+ cells (or you could try using outdated check cells). You want the cells to be DAT+ but not agglutinate until AHG phase. This may take a few tries to get down (if you have a procedure for making check cells it should work). Give it to your techs.

[Peggy]

Like David said Anti D is the easiest (no antigen typing required). We have MT students here and I do this frequently. Take any Rh positive patient, add anti-D. Rotate, incubate for about an hour or so(no less). Spin and it is ready to go. Works pretty good.

[Eagle Eye]

I do same as peggy. Take RH positive donor segments and add anti-D. It works very well. I use it to train my new emplyoee and MT students.

[galvania]

Coombs control cells (IgG) are the easiest - they're already sensitised

[Peggy]

I like the control cell suggestion, we seem to allways have plenty left at expiration

[NedB]

In the interest of combining 2 processes, why not use the diluted Anti-D you make up for serofuge recalibration mixed with Rh+ cells? We are few enough here that all of us get to do elutions. But I will keep what y'all have said in mind, because I see us having 'Main Lab' people in the Blood Bank in the future.

[Likewine99]

Anti-D with donor cells is easy, I've also used expired check cells. NedB you are correct to think that "main lab" people will be working in the BB in the future. Of the 20 techs I have that rotate through BB, only 1 is an SBB and dedicated and everyone else works 2 and often 3 other spots and some are PRN.

The anti-D eluate is clear cut and boosts their confidence level.

[skoopus]

What are the proportions of Rh+ cells to Anti D? Do you incubate at 37? I have new employees and Med Tech students to prepare for.

[AMcCord]

I have MT students and this is what I use for them:

You can use 4 D negative donor segments and 1 D positive donor segment + 3-5 drops anti-D. Incubate 1 hr at 37C, mixing occasionally. Trial and error will tell you how many drops to use to get the strength of reaction you want with your DAT - "jump out and slap them" strong or a little more subtle. 10 drops of Coombs control cells + 3 D negative donor segments also works well.

If you want something else, try 1 Jk(a) positive donor segment + 3 Jk(a) negative segments + 8 or 9 drops of anti-Jk(a). This works for Fy(a), Fy( and Jk(. Use outdated antisera or a patient sample that reacts strongly (you will have to incubate, check your DAT and maybe add more patient serum to make the patient antibody work well). Incubate the same as with anti-D.

Anti-e works well also and I usually have some that has outdated. Any Rh neg patient or donor sample will give you red cells. Use 3-5 drops antisera. You can add the anti-e (5 drops to 2 mL serum) and provide 1-2 mL e positive red cells to fake a warm auto absorption. Incubate the same as above.

For red cells, grab some extra segments when you check out blood to get segments to work with or retrieve some empty bags. You could also use some agreeable lab employees for red cell samples - do some antigen types on them and keep a list of who is good for the sample you want to make. I usually make a double batch for students as they often need more sample to work with until they refine their technique. I also usually wash once with saline to remove some of the excess antibody before I hand it over. These samples work better if they are used the same day or the next day at the latest.

Edited August 25, 2008 by AMcCord
additional info

[skoopus]

Thanks! This is really helpful. I'll put it in my bag of tricks!