How long can a T&S result last?

[Alice Chan]

If surgical dept perform OT 1 month after the pre-admission workup, can a TS result last for 1 month? What is the longest duration can TS lasts for untransfused patients?

[Mary]

We use the specimen for up to 10 days on untransfused patients.

[Franklyn]

The standards do not specify what the "pre surgical testing" window is. We keep our samples for 23 days (up to 21 days prior to surgery). The most important part of that process is the interview because only patients that are not pregnant, have not been transfused within a defined time period and have no history of unusual antibodies qualify for the program. Everyone else gets drawn/redrawn on the morning of the surgery.

[Alice Chan]

Thanks.

Do u freeze the original serum/plasma? U perform new T&S on that new sample? What is the purpose of this new sample? Can the patient transfuse before the 2nd T&S is completed? However, this will double your workload !

[Melanie]

It is really a matter of storage space. We save our samples for a total of five weeks. Samples are good for use for 28 days if not transfused or pregnant within the last three months. We save them for an additional week in case they get transfused on day 28.

We completed a validation of sample viability with all methods we use and found that they are still reactive at end of storage period.

[skopti]

We keep our samples for 24 days (21 + 3 post transfuion). I am not aware of any standards for retaining pre-surgical testing samples.

[marvy1]

I was looking into this issue a while back. I think it depends on whether you are doing computer crossmatching or not. If you are doing computer crossmatch, I haven't read anywhere how long (or short) a type and screen is valid if the patient has no recent history of pregnancy or transfusion. However, if you are still doing an immediate spin crossmatch, I would defer to others (Judd for one I believe???) who believe the best guideline for the stability of plasma in the reverse group (which equals the immediate spin) should be equal to what the manufacturer of your reverse cells recommends. In our case, that was 21 days. Sorry..I'm not at work so cannot confirm the reference at this moment. Some separate and freeze plasma for these "preop" patients although many frown upon separating cells and serum in blood banks (adds an additional level of risk of sample mixups)

[Franklyn]

The reason for a new specimen on the day of surgery for patients that flunk the Preadmission testing screening or that have unusual antibodies is so that we thoroughly screen the patients and provide correct components on the day of procedure. If you have been pregnant, received a transfusion or have a history of antibodies, your antibody screen results 21 days apart may be different. So we re-test and crossmatch on the new sample to ensure that the correct products are setup and to confirm that, even though they were pregnant or received a transfusion, no new antibodies have appeared. We only crossmatch and issue products based on the results of the new sample for these patients. If they were pregnant or transfused but upon screen negative initially AND on the day of procedure specimen, we will electronic crossmatch and issue. If they EVER had antibodies, we coombs crossmatch antigen negative units, only.

[Alice Chan]

Currently, we perform TS in pre-admission clinic & the surgery performed within 9 days. For non-pregnant & untransfused patients, we allow e-XM until the 9th day from TS. We kept the TS sample for 9 + 7 = 16 days (limited by storage space). But hospital tend to prolong the period between pre-admission clinic & exact surgical day. This raise the problem of finding reference guidelines for maximum duration of TS validity. Our intended solution is to perform TS only on the surgical day, otherwise the workload will be doubled. However, this may create 'urgent' calls from Operation rooms & cannot entertain the abs positive cases that demand special blood phenotypes.

[Ellen Zeigler]

If surgical dept perform OT 1 month after the pre-admission workup, can a TS result last for 1 month? What is the longest duration can TS lasts for untransfused patients?

There are several issues. By keeping a specimen for 1 month, you're potentially going to use it at one month to crossmatch. What was the FDA 510(k) approval for the evacuated tubes you're using? These vary depending on what the manufacturer submitted to the FDA. Are you doing an AHG x-match, if so, does your AHG have limitations as specified in the package insert?

[Eoin]

Risk Assessment and management. We use pre-admission assessment Group, Screen and Save extensively for our Ortopaedic patients. We say 28 days, but if within 5 days over, the Q Manager will personally ( or medical scientist if out of hours) check that patient has not been transfused two months prior to or since Save sample drawn and authorise on individual basis. Plasma held frozen for 5 weeks + 1 if subsequently transfused (to cover Tx reaction workup in case of DHTR).

Cheers, Eoin

[Liz0316]

Theoretically, as long as your patient has not been transfused or pregnant in the last 3 months, their immune status won't change. Once you have done your type and screen, within the time frame of manufacturer's instructions your specimen is good for however long you need it. Though, keep in mind it won't last for too many weeks! At our hospital we keep the specs for 1 month, although we tell the pre-admission office we keep them for 3 weeks - just in case there is a schedule change. It is really a matter of space.

[KKidd]

If retesting comes into play, what are the sample requirements for your anti-sera? I use EDTA specimens and testing with my Anti-D is limited to 7days .

.

[Yanxia]

I think we may take drug induced hemolysis into account.

There is a link http://www3.interscience.wiley.com/journal/71009042/abstract

If the patient had been found is DAT positive before transfusion, maybe treat it earlier . If duration between the T&S and the transfusion is too long, during this period the patient receive some drug, the antibodies status maybe change.