28-week RhIg dose

[scodina]

My blood bank stores and issues all RhIg doses for all OB patients. Our current outpatient (28-week dose) procedure is to draw a T&S on mom and armband her with a blood bank armband. If she is Rh-negative, we will recall her. If she returns within 72 hours with her armband on, we will give her RhIg. If she returns after the 72-hour window or cuts off her armband, we will re-armband her, redraw the T&S, and make her wait 3 hours while we test it prior to giving RhIg.

This is a ridiculous procedure that makes both the patient and the physician mad. I am trying to get buy-in from the hospital to change the current process. However, I can't find any data to support the idea that the prophylactic, 28-week dose of RhIg does not have to be given within 72 hours of the T&S test. Our BB Medical Director firmly believes that the woman could develop an anti-D after 72 hours and that we would not be able to discern Anti-D from passive Anti-D due to RhIg at the time of delivery (not that it would matter for the current pregnancy). My biggest argument right now is that patients will forgo any RhIg and develop real anti-D if we make the process too difficult.

This is the first hospital I have worked at that actually administered the antenatal dose of RhIg, so I am unsure if this is truly the practice in other locations. I have also tried to pull up the OB treatment recommendations for RhIg, but they just say "28 weeks." They don't list a specific timeframe from the ABO or antibody screen tests.

Help! I need suggestions

[Malcolm Needs ☆]

My blood bank stores and issues all RhIg doses for all OB patients. Our current outpatient (28-week dose) procedure is to draw a T&S on mom and armband her with a blood bank armband. If she is Rh-negative, we will recall her. If she returns within 72 hours with her armband on, we will give her RhIg. If she returns after the 72-hour window or cuts off her armband, we will re-armband her, redraw the T&S, and make her wait 3 hours while we test it prior to giving RhIg.

This is a ridiculous procedure that makes both the patient and the physician mad. I am trying to get buy-in from the hospital to change the current process. However, I can't find any data to support the idea that the prophylactic, 28-week dose of RhIg does not have to be given within 72 hours of the T&S test. Our BB Medical Director firmly believes that the woman could develop an anti-D after 72 hours and that we would not be able to discern Anti-D from passive Anti-D due to RhIg at the time of delivery (not that it would matter for the current pregnancy). My biggest argument right now is that patients will forgo any RhIg and develop real anti-D if we make the process too difficult.

This is the first hospital I have worked at that actually administered the antenatal dose of RhIg, so I am unsure if this is truly the practice in other locations. I have also tried to pull up the OB treatment recommendations for RhIg, but they just say "28 weeks." They don't list a specific timeframe from the ABO or antibody screen tests.

Help! I need suggestions

I totally agree with you that this, on the face of it anyway, is a ridiculous practice.

I absolutely agree that, the more difficult you make it for the pregnant lady, the more likely it is that she will not bother to come for the shot of anti-D immunoglobulin.

One question I have is, what if there is a foeto-maternal bleed 24 hours after the type and screen? The lady could well be sensitised in this time, if there has been a "silent" bleed prior to this and the bleed at 24 hours stimulates a secondary responce (but you sure as hell won't pick it up).

Secondly, what if there is a large, but "silent" bleed after the 28 week anti-D is given? How does your BB Medical Director expect you to then tell the difference between immune and prophylactic anti-D?

He/she might argue, "Yes, but how often is that likely to happen?" (either scenario).

I would ask, how many times have you detected anti-D in a pregnant mother after the 72 hours, without there being an overt sensitising event?

:eek::mad::mad::eek:

[mcgouc]

I have never worked in a hospital that gave the 28-week RhIG, but I worked in an outpatient lab where our routine work was type and screens on OB patients. Usually, the physician's office would draw the blood for the antibody screen and then give the RhIG to the patient on the same visit. Basically, they did a type and screen early in the pregnancy and an antibody screen (sometimes they repeated ABO/Rh) drawn just prior to the 28-week RhIG injection.

[Lcsmrz]

Our OB clinic draws a T&S at 28 wks, then injects the RhIg before she leaves.

[swede]

Our outpatient OB docs have us draw an antibody screen and administer the rhogam before the screen is complete. We do a quick type to make sure the lady is truly rh negative, but the screen is done later in the day. The path and the docs decided the convenience to the patient was the most important thing. We have followed this practice for many many years.

Some offices administer their own Rhogam, but send the antibody screen to us. Some offices send us the screen and give the rhogam themselves a week later.

[Eagle Eye]

we do T& S and is valid for week...in other words if patient comes bcak in a week we do not draw specimen and just give 1 vial of RhIg.

[rcollins]

Our policy also states we're allowed to issue the rhogam before the screen is complete. We do quick ABO/Rh and then release the rhogam if the patient is waiting. If they don't receive the rhogam at the time their type and screen is drawn then they have 7 days to come claim it. If they're not there within that time, they're redrawn.

I also agree that your current policy is probably discouraging moms from even going to get their rhogam! And that's no good!

Good Luck!

Becky

[jcdayaz]

We quite frequently, several per day, get 28ish week gestation ladies in our OPA (Outpatient Admitting) department for rhogam injections. We require a written order from the physician's office as well as a printed copy of lab results showing the RH status to be negative. Often times the patient's prenatal work (including a type and screen) was done by a different lab. We never do an antibody screen prior to antenatal rhogam injection.

[RR1]

We always have a sample drawn just moments prior to administering rhogam. Saves time and effort for everyone and is easier to interpret the origin of any anti-D detected in further samples.

[jcdayaz]

I totally agree with you that this, on the face of it anyway, is a ridiculous practice.

I would ask, how many times have you detected anti-D in a pregnant mother after the 72 hours, without there being an overt sensitising event?

:eek::mad::mad::eek:

I agree...TOTALLY ridiculous practice!!

To the second part..."How many times have you detected anti-D....." my guess is NEVER!!!!!!!!!!

"Sensitising event"... Our Dr's order Rh evaluations on any pregnant lady with any complications. Amniocentisis, bleeding, whatever. If there is an adverse avent ocurring in the pregnancy there is typically a rhogam ordered. (Duh, assuming the lady is Rh neg).

[jcdayaz]

Did I seroiusly just spell event as avent??? UUUGGGG!!!LONG DAY!!!!

[L106]

Usually, the physician's office would draw the blood for the antibody screen and then give the RhIG to the patient on the same visit. Basically, they did a type and screen early in the pregnancy and an antibody screen (sometimes they repeated ABO/Rh) drawn just prior to the 28-week RhIG injection.

Our physicians' offices stock and administer the RhIG, and the typical course of events in our lab are as mcgouc has described.

[LaraT23]

We currently do the pre antibody screen and the physician offices take care of the rhogam. My opinion is that you don't even need to band the patient. It isn't like you are matching a certain type of rhogam to the patient or that a vial for one person might be mixed up with one for another. That is what banding is there for, positive ID and matching of products. It doesn't seem to be needed in that case.

I would just throw out the banding thing and do the screen and issue the rhogam without it. Sometimes when we really think of why we are doing something, it turns out it doesn't make sense.

[Malcolm Needs ☆]

Sometimes when we really think of why we are doing something, it turns out it doesn't make sense.

I agree, but in this case it did not take a lot of thinking to know that the procedure invented by the Medical Director made no sense whatsoever!!!!!!!!!!!!!!!!

:eek::eek:

[lgabbert]

Our facility does not band patients for rhogam. It is difficult enough to get outpatients who are receiving blood to keep the wristband on, much less OB patients, especially for 72 hours! I bet you don't get reimbursed for the second type and screen either.

I have been wondering if we can drop the antenatal screen altogether. What do the rest of you do?

[Malcolm Needs ☆]

I have been wondering if we can drop the antenatal screen altogether. What do the rest of you do?

Sorry to be a pain, but could you explain this a bit more please?

Do you mean post-Rhogam, or just drop the screen full-stop?

:confused:

[CABMT]

Our patients have the blood drawn and RhIG is given during the same visit.

I am interested to hear other opinions about the interval length from when the T&S is done and the RhIG is given. We've generally used a 2 week time frame; if the patient requires RhIG and we've done a T&S within 2 weeks prior, we do not repeat the testing. I have not seen any standards on this subject but this scenario does happen with some frequency and it seems a waste of time and money to be repeating the testing when we know she qualifies for the injection. Other comments?? Thanks

[LAS]

We do type/screen and issue Rhogam when complete. If the patient cannot wait, she can return up to 3 days later and still receive the injection. We do not armband these patients. Frequently the docs send the patients over for a gestational diabetes screen at the same time, so they are here for a while anyway.

[Kimster]

This is where the differences between AABB and ACOG guidelines do not mesh. AABB guidelines have a prenatal antibodies screen to be performed prior to the 28 wk administration of Rh Immune Globulin. ACOG leaves this to the discretion of the the physician. With blunt trauma, (falls, car accidents, domestic abuse) being the number one reason a Rh negative pregnant women becomes sensitized and the state of defensive medicine, the wise choice would be to draw the type and cross, perform the antibody screen after the administration of the Rh Immune globulin if the mother is Rh negative. This will prevent the mom from waiting but will still be covered and no one is worried whether or not she will come back. Many blood banks do it this way. If she has become sensitized prior to the 28 week administration, one does of Rh Immune Gobulin will not hurt her or the fetus.

[younglau]

We have an outpatient clinic that supplies our 28 week Rhig shots, however we are responsible for the testing and follow-up of these patients. The physicians provide the clinic with a Group and Screen result from this pregnancy (we have very little control over the timing of this draw as we only test some of them ourselves) Based on this information they are given their Rhig ,specimen is drawn prior to injection and sent to us to be tested. We do have to play detective and track down passive anti-D's from previous Rhig injection due to bleeds, amnios, CVS etc and yes there are the occasional alloimmunized mothers, we can never be 100% certain that it is a newly developed antibody or one that was undetected by the laboratory providing the original testing.

I have worked in hospitals where they will only use their own testing for the issue of Rhig and the sample must have been drawn between 24-27 weeks gestation. I much prefer it the control that this gives.

[adiescast]

The OB clinic gives the shot at 28 weeks. They draw the type and screen before they give it, but they do not wait for the screen results.

[lgabbert]

Sorry to be a pain, but could you explain this a bit more please?

Do you mean post-Rhogam, or just drop the screen full-stop?

:confused:

I mean no type and screen at the 28 wk visit.

We do a type and screen on all the clinic OB's for their first OB visit. Therefore, we usually have records for the patients. What is the purpose of doing the T&S at the 28 wk visit, other than to confirm whether the patient has or has not been sensitized from the previous screen? As I understand, the reason for waiting until 28 wks for the antenatal rhogam is that the fetus does not have enough blood volume to produce an antibody reaction, so the chances of the patient being sensitized before that should be very low.

If they have been sensitized, would the physician not give the rhogam? I think some of ours would still give rhogam.

What are your thoughts on this? Am I on the wrong track altogether?

[adiescast]

It is helpful to know early in a pregnancy whether the mother has any antibodies that could affect the fetus. Anti-D is not the only antibody that can cause HDN.

We also use a negative screen from early in the pregnancy to help sort out whether the anti-D we detect later is from the RhIg or might be immune.

[John C. Staley]

All we did for antenatal RhIG was an antibody screen. The docs that orderd them just wanted the screen. They already had an ABO/Rh. Some docs had their own Rhig, others, we provided but we NEVER gave the injection.

[Malcolm Needs ☆]

I mean no type and screen at the 28 wk visit.

We do a type and screen on all the clinic OB's for their first OB visit. Therefore, we usually have records for the patients. What is the purpose of doing the T&S at the 28 wk visit, other than to confirm whether the patient has or has not been sensitized from the previous screen? As I understand, the reason for waiting until 28 wks for the antenatal rhogam is that the fetus does not have enough blood volume to produce an antibody reaction, so the chances of the patient being sensitized before that should be very low.

If they have been sensitized, would the physician not give the rhogam? I think some of ours would still give rhogam.

What are your thoughts on this? Am I on the wrong track altogether?

It very much depends on how often the lady's plasma is screened for atypical alloantibodies prior to 28 weeks gestation.

In the UK, the plasma is often screened at booking, and, if there are no atypical alloantibodies detected, they are not screened again until 28weeks gestation. This, in effect, is the last chance to detect clinically significant atypical alloantibodies that have developed between the booking sample and the 28 week sample.

As adiescast quite correctly says, anti-D is not the only atypical alloantibody that can cause very serious hemolytic disease of the newborn/foetus; anti-K immediately springs to mind. If you miss an anti-K, becuase you abandon the 28 week gestation screen, you could end up with a very anaemic, if not dead, baby.

It is extremely rare for a de novo atypical alloantibody developing in the third trimester to cause clinically significant haemolytic disease, and so we do not tend to screen after the 28 week sample.

So, as I say, it depends on the number of screens and the timing of the screens, but I certainly would not advocate abandoning the 28 week screen (and, in any case, in the UK, this screen is written into the BCSH Guidelines on testing during pregnancy).

:salute: